bio 210 anatomy & physiology i lecture
TRANSCRIPT
BIO 210
ANATOMY & PHYSIOLOGYI
LECTURE OUTLINE
Prepared by
David T. Corey, Ph.D.Science Department
Midlands Technical CollegeP.O. Box 2408
Columbia, SC 29202
All rights reserved by David T. Corey, 2001
ANATOMY & PHYSIOLOGY ILECTURE OUTLINE
BIO 210
David T. CoreyMidlands Technical College
Science Department, Beltline CampusP.O. Box 2408
Columbia, SC 29202
Copyright © 2001
All rights reserved. No part of this outline may be reproduced, stored in a retrieval system, or transcribed, in any form or by any means - electronic, mechanical, photocopying, recording, or otherwise without prior written permission of David T. Corey.
TABLE OF CONTENTS
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Subject Page
The Human Body: An Orientation 5
Chemistry Comes Alive 12
Cells: The Living Units 20
Tissues: The Living Frabric 28
The Integumentary System 33
Bone & Bone Tissue 38
Joints 42
Muscles & Muscle Tissue 45
The Muscular System 49
Fundamentals of the Nervous System & 52 Nervous Tissue
The Central Nervous System 59 The Peripheral Nervous System & Reflex 65 Activity
The Autonomic Nervous System 68
Neural Integration 71
The Special Senses 75
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THE HUMAN BODY: AN ORIENTATION
Anatomy - is the study of the shape and structure of the human body and the
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relationship between body parts.
Physiology - is the study of the functions of the body parts. How the body parts work & carry out their life-sustaining activities.
Anatomy & Physiology are two major branches within the field of Biology.
Biology - is the study of all forms of life.
BRANCHES OF ANATOMY1). Gross Anatomy - study of large observable structures without the use of magnification. - Morphology - the study of shape. Three major Divisions a. Regional Anatomy:
b. Systemic Anatomy:
c. Surface Anatomy:
2). Microscopic Anatomy - study of small observable structures with the use of magnification.
Two subdivisions A. Cytology: - the study of the structure, function, and development of cells that make up the different body parts.
B. Histology: - the study of tissues and organs making up the entire body of an organism.
3). Developmental Anatomy
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- studies the growth and development of an organism during its life time. - Embryology - study of an organism from fertilization to birth.
4). Comparative Anatomy - Compares the body parts and functions between organisms.
Highly Specialized Branches of Anatomy1). Pathological Anatomy:
2). Radiographic Anatomy:
3). Molecular Biology:
Specialized Areas of Physiology1). Renal Physiology:
2). Neurophysiology:
3). Cardiac Physiology:
MAINTENANCE OF LIFE
What are life functions?
- a series of highly organized and related activities which allow living things to live, grow, and maintain themselves.
What are the vital life functions? - maintenance of boundaries - movement (contractibility) - responsiveness or irritability - ingestion
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- digestion - transport - respiration - synthesis - assimilation - growth - secretion - excretion - reproduction
SURVIVAL NEEDS- food - nutrients- water- oxygen- temperature- pressure
THE HIERARCHY OF STRUCTURAL ORGANIZATION
1). Atoms OR Ions2). Molecules and compounds3). Cells containing cell organelles4). Tissues5). Organs6). Organ Systems7). Organisms (Organismal level)8). Populations9). Communities10). Ecosystems11). Biosphere
BODY PROCESSES Metabolism - functional activities of cells ie. growth, repair, energy release, food use, secretions - sum of all chemical reactions within the cell
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- consists of two processes 1. Anabolism - building up of complex materials from simpler ones
2. Catabolism - breaking down of complex materials into simpler ones with the release of energy
Homeostasis - The maintenance of a rather stable internal environment - Human survival depends on maintaining and/or restoration of homeostasis!! - Control: control center = receptor =
effector =
- Negative Feedback Mechanisms:
- Positive Feedback Mechanisms:
- Homeostatic Imbalance:
ANATOMIC TERMINOLOGY
Anatomical position - standing erect, face forward, arms at the side, and palms forward.A. REGIONAL TERMS 1. Axial part:
2. Appendicular part:
B. BODY PLANES & SECTIONS 1. Frontal (coronal):
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2. Sagittal (median):
- midsagittal:
- parasagittal:
3. Transverse (Horizontal) - divides body into superior & inferior - cross section:
- oblique plane:
C. LOCATION, POSITION, OR DIRECTIONAL TERMS (Table 1.1, p. 18)
1. Anterior (ventral) 2. Posterior (Dorsal) 3. Cranial 4. Caudal 5. Superior vs inferior 6. Medial (mesial) vs lateral 7. Proximal vs distal 8. Superficial vs deep 9. External vs internal
D. SPECIFIC BODY AREAS
- Know all the terms on p. 12, Fig. 1.7
E. BODY CAVITIES & MEMBRANES 1. Dorsal Cavity - cranial cavity:
- spinal (vertebral) cavity:
2. Ventral Cavity a. Thoracic cavity - pleural cavities (lungs)
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- pericardial cavity (heart) - mediastinum
b. Abdominopelvic cavity - abdominal cavity: below the ribs - pelvic cavity
3. Serous Membranes:
- parietal:
- visceral:
4. Mucous Membranes:
E. OTHER BODY CAVITIES 1. Orbital: eyes, optic muscles, optic nerves, tear ducts 2. Nasal: nose 3. Buccal (oral): teeth and tongue 4. Middle ear D. ABDOMINOPELVIC REGIONS (9) 1. Upper - Right & Left Hypochondriac - Middle: Epigastric
2. Middle - Right & Left Lumbar - Middle: Umbilical 3. Lower - Right & Left Iliac (Inquinal) - Middle: Hypogastric (Pubic)
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CHEMISTRY COMES ALIVE
WHY study chemistry in an Anatomy & Physiology Class?
Chemistry - is the study of the structure of matter, the composition of substances, their properties, their chemical reactions, and synthesis.
- examples of chemical reactions: digestion of food
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formation of urine manufacture of proteins
Matter - anything that has weight and occupies space.
- composed of chemical elements. - gases, liquids, solids
Matter can be divided into two categories 1. Biotic: living material such as plants and animals 2. Abiotic: None living material such as rocks and rain
Chemical Elements - are substances that can not be broken down by chemical means into simpler substances.
Biochemistry - the study of chemical reactions of living things
Atom - the smallest piece of an element and is invisible to the human eye
- composed of subatomic particles 1. protons: + electric charge, found in the nucleus 2. neutrons: no electric charge, found in the nucleus 3. electrons: - electric charge, found around the nucleus in orbital rings.
Atomic number:
- No. of protons = No. of electrons in an atom, therefore atoms are electrically neutral.
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What if the number of protons does not equal the number of electrons?
You have a charged atom called an ion.
Isotopes: same number of protons, but the number of neutrons is differention
Radioisotopes: exhibit atomic decay which is called radioactivity - unstable and decay to more stable forms by emitting alpha, beta, or gamma rays
- can be used for diagnosis
- all types damage living tissue
Atomic symbol:
ELEMENTS
- 92 naturally occurring elements 1. 26 are found in the human body 2. 18 are trace elements
THE SIX MOST IMPORTANT ELEMENTS OF THE HUMAN BODY ARE:1). Oxygen (O): 65%2). Carbon (C): 18.5%3). Hydrogen (H): 9.5%4). Nitrogen (N): 3.2%5). Calcium (Ca): 1.5%6). Phosphorus (P): 1.0%
Molecule:
COMPOUNDS:
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- elements combined together in a definite proportion by weight
examples: Water = H20
Table Salt = NaCl Hydrochloric acid = HCl Sodium bicarbonate = NaCHO3 Glucose = C6H12O6 Carbon dioxide = CO2 Carbon monoxide = CO
What is a molecular formula?
MIXTURES
- composed of two or more components physically intermixed together Three basic types: 1). Solutions:
a. solvent:
b. solutes:
2). Colloids:
3). Suspensions:
COMPOUNDS CAN BE DIVIDED INTO TWO GROUPS1). INORGANIC COMPOUNDS
- Backbone consists of a metal (examples Al, Au, Ag, Pb) - usually do not contain both Carbon & Hydrogen at the same time - tend to have relatively few atoms - found in living organisms - tend to have ionic bonds
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EXAMPLES: Water Acids and Bases Salts Carbon dioxide Oxygen
2). ORGANIC COMPOUNDS - Most contain both Carbon and Hydrogen at the same time. (examples of organic cpds without both C & H: graphite, diamonds) - tend to have many atoms - tend to be larger than inorganic compounds - tend to have covalent bonds - more than a million known organic compounds
EXAMPLES: Carbohydrates Lipids Proteins Nucleic Acids
INORGANIC COMPOUNDS
WATER - most abundant and important inorganic compound found in living material - 60 to 80% of volume
ACIDS - a substance that when dissolved in water, will ionize into positively charged hydronium ions (H3O+) or Hydrogen ions (H+)
and negatively charged ions of some other element EXAMPLE: HCL + H2O è H3O+ + Cl-
BASES - a substance that when dissolved in water, ionizes into negatively charged hydroxide (OH-) ions and positively charged ions of a metal.
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EXAMPLE: NaOH è Na+ + OH-
NEUTRALIZATION - when an acid and a base are combined, they form a salt and water HCL + NaOH è NaCl + H2O
Electrolytes:
pH - is a measure of the acidity or alkalinity (basicity) of a solution. - pH scale - ranges from 0 to 14 - 7.0 is neutral - > 7.0 is basic - < 7.0 is acidic
EXAMPLES: Human tears pH = 7.3 Acidic or basic? Human blood pH = 7.4 Acidic or basic? Human urine pH = 6.0 Acidic or basic? Water pH = 7.0 Acidic or basicBUFFERS - help a living organism to maintain a constant pH value which contributes to homeostasis.
ORGANIC COMPOUNDS
A. CARBOHYDRATES - Contain carbon, hydrogen and oxygen - Primary source of nutrient energy for cells (Glucose) - some structure - Sugars
DIVIDED INTO THREE GROUPS 1). Monosaccharides - sugars which can not be broken down any further - single or simple sugars
EXAMPLES: Glucose - blood sugar
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Fructose - fruits & honey Galactose - Agar 2). Disaccharides - Double sugar
Examples: Sucrose - table sugar Maltose - malt sugar Lactose - milk sugar
Dehydration - synthesis of a large molecule from small ones by the loss of a water molecule.
Hydrolysis - a large molecule is broken down into smaller molecules by the addition of water.
3). Polysaccharides - large complex molecules made up of hundreds to thousands of glucose molecules (or other simple sugar) bonded together in one long chainlike molecule.
EXAMPLES: Starch - made in plant cells (storage form of Glucose) Cellulose - gives support to plant cells Glycogen - storage form of Glucose in animals
B. LIPIDS - contain carbon, hydrogen, oxygen - also called fats
DIVIDED INTO THREE MAJOR GROUPS1). FATS & OILS (Neutral Fats; triglycerides) - made up of glycerol and fatty acids - also called triglycerides - high energy storage, most abundant type
2). PHOSPHOLIPIDS - found in cell membranes, the brain and nervous tissue
3). STEROIDS - contain cholesterol
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Is all cholesterol bad?
- essential in the structure of a semipermeable cell membrane - Vitamin D - Hormones C. PROTEINS - Carbon, hydrogen, oxygen, nitrogen and usually sulfur and phosphorus - important in outer coat of viruses - binding and structural components of all living things - made up of amino acids: amine:
organic acid group:
- enzymes are specialized proteins control chemical reactions by acting as catalysts affects rate and speed of chemical reactions used over and over very specific
cofactor:
coenzyme:
D. NUCLEIC ACIDS - Carbon, hydrogen, nitrogen, phosphorus
TWO TYPES1). DNA = deoxyribonucleic acid - carries the genetic information
2). RNA = ribonucleic acid - help in synthesizing proteins Three types a. mRNA b. tRNA c. rRNA
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E. ADENOSINE TRIPHOSPHATE (ATP)
ATP synthesis is an all-important cellular function because it provides a form of chemical energy that is usable by all body cells!
CELLS: THE LIVING UNITS
The cell is the basic unit of structure and function of all living things.
Extracellular fluid: interstitial fluid, derived from blood, bathes cells - consists of: amino acids, fatty acids, vitamins, hormones, neurotransmitters, salts, waste products
Shape of cells is vaiable!Cell length: few micrometers to well over a meter - muscles - nerves
Trillions in the human body!
PLASMA MEMBRANE (Cell membrane) - surrounds the cell
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- separates the cell's cytoplasm from the external environment and from neighboring cells. - "selectively, semi-, or differentially permeable" - made-up of protein and lipids - double layer of phospholipid molecules with proteins and cholesterol dispersed in it
Why are proteins important?
hydrophobic end = "tail": hydrocarbon fatty acid chains
Hydrophilic end = "head": polar phosphorus-containing end
Microvilli - cilia, increase membrane surface area - functional "mechanical stiffener"
Types of Junctions (3) 1). Tight junctions: protein's membranes adjacent to each other fuse together like a zipper, impermeable junction ex. epithelial cells lining digestive tract and adjacent blood vessels 2). Desmosomes: anchoring, adhesion, coupling along sides of abutting cells
3). Gap junctions: allow direct passage of chemical substances between adjacent cells
Cytoplasm - cellular material found between the nucleus and the plasma membrane. - site for most cellular activities - protein synthesis - anaerobic respiration
3 Major Elements 1). Cytosol: viscous, semitransparent fluid - mostly water (70 to 90%) - proteins, lipids, minerals, salts and carbohydrates
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2). Cell organelles:
3). Inclusions:
Protoplasm - Includes both the cytoplasm and the nucleus
THE NUCLEUS
Nucleus - controlls the activities of the cell - facilitate cell division = Mitosis - DNA and proteins - semi-fluid medium called nucleoplasm
Nucleolus (Nucleoli) - located within the nucleus, none membrane bound - produce ribosomes which will eventualy be released into the cytoplasm - usually 1 or 2 per cell, but may have more - RNA
Nuclear membrane - surround nucleus - double layer with openings
Chromatin - granular, threadlike material composed of DNA and histone proteins
CYTOPLASMIC ORGANELLESRibosomes - Consists of protein and RNA - sites of protein synthesis
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Centrosome - enclose the centrioles
Centrioles - two cylindrical organelles perpendicular to each other - form spindle fibers during cell division - used to move and organize the chromosomes.
Endoplasmic Reticulum - provides passageway for transport - site for many chemical reactions - provides some internal support
Two types of ER 1). Rough:
2). Smooth:
Mitochondria - site of aerobic respiration - ATP production - "Power-house" - Double membrane cristae:
matrix:
- self replicate: contain both DNA & RNA. Fission:
Golgi apparatus - flatten membranous sacs - stores and packages secretions for discharge from the cell - form the lysosomes Lysosomes - contain powerful digestive enzymes (acid hydrolases) - digest worn out cell organelles and foreign matter (Intracellular digestion)
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- Autolysis:
Cilia/flagellum
Cytoskeletal Elements 1). Microfilaments:
2). Microtubules:
MOVEMENT OF MATERIALS ACROSS PLASMA MEMBRANE
Passive transport: Does not require energy input from the cell 1). Diffusion:
2). Facilitated Diffusion: 3). Osmosis:
a. Isotonic:
b. Hypertonic: - more solutes outside cell, ie. cells lose water by osmosis and shrink
c. Hypotonic: - less solutes outside cell, ie. cells take in water and swell, may lysis
4). Filtration:
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Active transport: process in which molecules move across a cell membrane from an area of lower concentration to an area of greater concentration (against a concentration gradient).
- Requires energy (ATP) from the cell TYPES 1). Carrier molecule:
2). Endocytosis (2)
a. Phagocytosis:
b. Pinocytosis:
3). Exocytosis:DISORDERS OF CELL STRUCTURE
Tumor (Neoplasms):
Divided into two groups1). Benign:
2). Malignant (Cancer):
Metastases - movement of a malignant tumor
THE CELL CYCLE- process of producing new cells by division of existing cells includes: Interphase, mitosis and cytokinesis
Two distinct processes of cell division:1). Mitosis:
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2). Cytokinesis:
STEPS IN THE CELL CYCLE 1). Interphase
- metabolic activities of the cell to maintain homeostasis - replication of DNA - growth in all 3 subphases - protein synthesis
3 Subphases 1). G1:
2). S: 3). G2:
2). MITOSIS
When does a cell divide?
A. Prophase
- centrioles move toward the poles - nuclear membrane dissappears - Chromosomes become visiable - spindle fibers form
B. Metaphase
- chromosomes line up by their centromere along the equatorial plane - spindle fibers
C. Anaphase
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- Chromosomes separate into chromatids by shortening of the spindle fibers - Chromatids pulled toward the poles
D. Telophase
- Chromatids have reached the poles and begin to uncoil - nuclear membrane reappears - spindle breaks down and disappears
3). CYTOKINESIS
- division of the cytoplasm which results in two daughter cells identical to the original cell - begins in late anaphase, but not visible until Telophase
PROTEIN SYNTHESIS
Gene:
Transcription:
Translation:
3 Forms of RNA
1). mRNA:
2). rRNA:
3). tRNA:
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TISSUE: THE LIVING FABRIC
What is a tissue?
FOUR MAIN TYPES OF TISSUES1). Epithelial2). Connective3). Muscle a. skeletal b. cardiac c. smooth4). Nervous
What is an organ?
What is an organ system?
EPITHELIAL TISSUE A. Functions 1.) protection:
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2). secretions:
3). regulate passage:
4). cover:
5). filtration:
6). absorption:
7). excretion:
B. TWO MAJOR GROUPS OF EPITHELIUM 1). Covering & lining epithelium:
2). Glandular epithelium: - secretions:
2 Types a. Endocrine glands: ductless - hormones
b. Exocrine glands: duct - vary diverse
Types of Exocrine glands 1). Goblet cells:
2). Merocrine gland:
3). Holocrine gland:
4). Apocrine gland:
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C. CHARACTERISTICS OF EPITHELIUM 1). Very little extracellular material, cells packed tightly together
2). Always has one free surface - apical surface - basal surface connected to a nonliving adhesive material called the basal lamina
- basal lamina connected to the nonliving reticular lamina of the connective tissue
- basal lamina + recticular lamina = basement membrane
3). Contains no blood vessels - avascularity - nourished by substances diffusing from blood vessels in underlying connective tissue
4). Undergo rapid cell division
D. Classification (All are polyhedral in shape) 1). Number of cell layers a. simple:
b. stratified:
c. pseudostratified:
2). Shape of cells a. squamous:
b. cuboidal:
c. columnar:
2). Covering and lining a. ciliated vs nonciliated
b. keratinized or nonkeratinized
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CONNECTIVE TISSUE
A. Functions 1). Support and Connect (Binding):
2). Protection:
3). Storage:
4). Insulation:
B. Characteristics of Connective Tissue 1). Derived from Mesenchyme 2). Degrees of vascularity 3). Few cells surrounded by a nonliving intercellular matrix a. Ground substance:
b. Fibers:
Three types 1. Collagen 2. Elastic 3. Reticular
c. Cell: 4). Not exposed to external environment C. Types of Connective Tissue
CONNECTIVE TISSUE PROPER 1). Adipose: 2). Loose (Areolar): 3). Dense fibrous:
Types of Dense fibrous Connective Tissue a. Regular:
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b. Irregular: c. Elastic:
4). Supportive:Types of Supportive Connective Tissue
a. Osseous (Bone): b. Cartilage: 1. Hyaline: 2. Fibrocartilage: 3. Elastic: 5). Vascular:
Types of Vascular Connective Tissue a. Blood: b. Lymph:
MUSCLE TISSUEA. Skeletal - striated and voluntary - multinucleated
B. Cardiac - striated and involuntary - 1 or 2 nuclei C. Smooth - nonstriated and involuntary - uninucleated
NERVOUS TISSUEA. Function - Irritability: ability to respond to environmental changes - Conductivity: ability to carry a nerve impulse
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B. Composition 1). neurons:
2). Neuroglial cells:
THE INTEGUMENTARY SYSTEM
Major components: 1). Skin: tough and pliable - also called: integument, cutaneous membrane, epidermis
2). Derivatives: Hair, nails, glands (sweat & oil)
Functions: 1). Covers
- 1.5 to 2 m2 surface area - ~ 9 lbs - 1.5 to 4 mm thickness
2). Protection - ultraviolet radiation - protective covering: abrasion dehydration, injury, germ invasion - chemical barrier What is a germ? What is a pathogen?
3). Helps in regulating body temperature - heat loss - evaporation: perspiration
4). Excretion - organic wastes, salts, water
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5). Sensory perception - receptors temperature (heat & cold), pain, pressure, touch - free nerve endings
6). Temporary storage - fats, glucose, water, salts - blood
7). Absorption - certain drugs 8). Synthesis of Vitamin D - Bone formation, calcium metabolism, teeth
TWO BASIC LAYERS OF SKINA). EPIDERMIS: 35 to 45 days - outermost covering which is composed of epithelial cells and lacks blood vessels
- epithelial cells: stratified squamous epithelial cells keratinized or nonkeratinized: depends on location
keratinized =
nonkeratinized =
Keratinocytes: keratin - fibrous proteins, hard, nonliving which makes the epidermis waterproof Five layers of the epidermis 1). Stratum corneum - outermost layer, 20 to 30 cell layers thick, ~ 75% of total epidermal thickness - first line of defense - outward thickening = callus - inward thickening = corn
2). Stratum lucidum: absent in thin skin areas of the body
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3). Stratum granulosum: keratinization begins, cells begin to die
4). Stratum spinosum: some cell division
5). Stratum basale - inner most layer, most of the cell division
Stratum spinosum and stratum basale = stratum germinativum
Melanocytes - cells responsible for skin pigmentation - found in the stratum basale - produce melanin yellow to brown to black color amount and color determines skin color Three pigments involved in skin color: 1). Melanin:
2). Carotene: yellow to orange
3). Hemoglobin: crimson
Freckles - patches of melanocytes in the skin
Albinism - absence of pigments
Sun Tan - increase production of melanin for protection from ultraviolet radiation
How long does it last?
B). DERMIS (corium) "ANIMAL HIDE" - thick inner layer, and thickness varies: soles of feet and palms of hand = thick shoulders and back = thinner, but thicker than abdomen and thorax
- contains: elastic fibers
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nerve endings arrector pili muscle receptors: touch, temperature, pain, pressure blood vessels
lymphatic vessels
(oil and sweat glands, finger nails, and hair follicles are derived of the epidermis not the dermis!)
Two Layers of Dermis1). Papillary:
Finger prints - results from the dermal papillae ridges in the skin
2). Reticular: ~ 80% of the dermis
Burns1). First degree:
2). Second degree:
3). Third degree:
4). Fourth degree:
C. SUBCUTANEOUS LAYER (Hypodermal layer or superficial fascia) - NOT a true layer of the integumentary system - loose connective tissue and adipose - about 50% of the bodies stored fat; shock absorber, insulate - site of injections: hypodermic - attaches integument to muscles or underlying organs
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ACCESSARY STRUCTURES OF THE SKIN1). Hair: 3 layers - outer = cuticle: single layer of flat keratinized cells, overlap - middle = cortex: elongated, keratinized, nonliving cells, contains hair pigment - inner = medulla: may also contain pigment
Parts = root: implanted in the skin in an inpocketing called the hair follicle = shaft: extends out from the epidermis, shape determines if hair is straight or curly
- color = melanocytes at base of hair follicle
- Goose bumps: Arrector pili muscles contract
2). Nails: epidermis is hard and keratinized to a greater degree - protection
3). Sweat glands: regulate body temperature = sudoriferous glands - water, salts, organic waste ~ 2.5 million
Two Types a). Eccrine:
b). Apocrine:
A). Ceruminous glands = wax glands: secretes cerumen - found in the ear canals "earwax" B). Mammary glands = specialized sweat glands modified to secrete milk
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4). Sebaceous glands "Oil" - are simple alveolar glands which secretes sebum: lubricates the skin, keeping it soft and pliable - inhibits bacterial growth - reduces evaporative water loss Vernix caseosa:
BONES AND BONE TISSUE & SKELETAL SYSTEM
Major Functions: 1). Support:
2). Shape and Form: 3). Protection:
4). Movement and anchorage of muscles:
5). Storage of minerals and fats: - Ca, P, K, Na, Sulfur (S), Magnesium (Mg), Copper (Cu) 6). Hemopoiesis (Hematopoiesis):
TWO BASIC TYPES OF OSSEOUS TISSUE1). Spongy: - Trabeculae: form network of spaces
2). Compact:
TYPES OF BONE1). Long:
2). Flat:
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3). Irregular:
4). Short:
STRUCTURE OF A LONG BONE1). Diaphysis2). Epiphyses3). Periosteum4). Endosteum5). Medullary cavity6). Yellow marrow7). Red marrow8). Spongy bone9). Compact bone10). Articular cartilage11). Epiphyseal plate (line, disc)12). Sharpey's fibers
COMPACT BONE CELL STRUCTURE1). Bone cell = osteocyte2). Canaliculi3). Haversian canal (osteonic canal)4). Lacuna5). Lamella6). Volkmann's canal (Perforating)7). Osteon (Haversian system)
SPONGY BONE- No osteon- Trabaculae with irregularly arranged lamellae- osteocytes interconnected by canaliculi
BONE FORMATION1). Osteoblasts =
2). Osteoclast =
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OSSIFICATION (OSTEOGENESIS)1). Formation of the bony skeleton2). Bone growth3). Remodeling and repair: injuries, additional bone strength neededFormation: Bone tissue begins to develop around week 6A. Intramembranous ossification 1. Most skull bones and clavicles - flat 2. Bone replaces fibrous connective tissue membranes 3. Steps a. Formation of bone matrix within the fibrous membrane b. Formation of woven bone and the periosteum c. Formation of compact bone plates
B. Endochondral ossification 1. Begins third month of development 2. Hyaline cartilage 3. Most skeletal bones
C. Bone Growth 1. Growth in length of long bones a. Females to about age 18 b. Males to about age 20-21 2. Appositional Growth - increase in thickness (diameter) 3. Hormones a. Growth hormone - anterior pituitary gland b. Thyroxine - thyroid gland c. Testosterone d. Estrogen e. Calcitonin - thyroid gland
f. Parathyroid hormone - parathyroid glands
PARTS OF THE SKELETAL SYSTEM
COMPONENTS: Bone, Cartilage, Joints, Ligaments
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How many bones?
~ 20% of the body mass
Divided into two main parts:1). Axial: - forms the long axis of the body - central support - protects internal organs - skull, vertebral column, ribs, sternum, hyoid bone
2). Appendicular: bones of the upper and lower extremities and the girgles that attach them to the axial skeleton
- pectoral girdle:
- pelvic girdle:
SOME COMMON DISORDERS1). Fracture:
2). Dislocation:
3). Sprain:
4). Strain:
5). Arthritis:
Rheumatoid -
Osteoarthritis -
6). Curvature of the spine: Scoliosis -
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Kyphosis -
Lordosis - JOINTS
Joints or articulations:
Functions of joints1). 2).
CLASSIFICATION OF JOINTS
A. FUNCTIONAL: Based on the amount of movement allowed at the joint
3 Types of Functional Joints1). Diarthroses = freely movable joints - most of our joints - examples: knee, elbow
2). Amphiarthroses = partially movable joints - example: attachment of the ribs to the spine
3). Synarthroses = immovable joints - example: adult skull (sutures)
- frontanel: soft spot on baby's head, i.e. no bone
B. STRUCTURAL JOINTS:
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Three types of Structural Joints1). fibrous:
a. sutures -
b. syndesmoses -
c. gomphoses - fibrous joint between a tooth and its bony alveolar socket
2). cartilaginous:
a. synchondroses - sites of bone growth, hyaline cartilage unites bones
b. symphyses -
- designed for strength with fexibility
3). synovial - - all joints of the limbs, most joints of the body
General Structure of Synovial Joints a. Articular cartilage:
b. Joint Cavity:
c. Articular capsule:
d. Synovial fluid:
e. Reinforcing ligaments:
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Bursa: a sac in which fluid is secreted, reduces friction between a tendon and a bone.
Types of Synovial Jointsa. Plane joints:
b. Hinge joints:
c. Pivot joints:
d. Saddle joints:
e. Ball-and-socket joint:
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MUSCLES & MUSCLE TISSUE
MAJOR COMPONENTS1). Muscles: skeletal, cardiac, smooth
2). Tendons:
3). Aponeurosis:
4). Raphe:
MAJOR FUNCTIONS1). Movement
2). Maintain posture
3). Joint stability
2). Heat production
Muscles account for ~ 40% of the body mass - ~ 36% in females - ~ 42% in males Differences due to testosterone effects on skeletal muscle in males
CHARACTERISTICS OF MUSCLES1). Contractibility:
2). Extensibility:
3). Elasticity:
4). Irritability (Excitability):
Skeletal muscle
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- attached to bone or to skin - striated, voluntary, multinucleated cells - single, very long, cylindrical fibers - speed of contraction slow to fast
Skeletal Muscle Structure
TendonFasciaEpimysiumPerimysiumFascicleEndomysiumMyofibrilsFilaments: actin (Thin filaments) & myosin (Thick filaments)SarcomereZ - lineSliding Filament MechanismCrossbridgesTransverse tubules (T-tubules)A bandI bandH zoneM lineMotor unitNeuromuscular junctionSynaptic cleftSynaptic vesiclesAcetylcholinePower strokeThreshold stimulusAll-or-None responseRigor mortisMuscle fatigueOxygen debtMyoglobinHemoglobin
Creatine phosphate (CP) CP + ADP Creatine + ATP
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Lactic acid
TERMS:1). Antagonist -
2). Prime mover -
3). Synergist -
4). Fixators -
Three periods in a muscle contraction:1). Latent period:
2). Period of contraction:
3). Period of relaxation:
Isometric contractions:
Isotonic contractions:
Change in skeletal muscle due to exercise1). Atrophy:
2). Hypertrophy:3). Sarcoplasm:
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4). Muscle efficiency:
5). Muscle strength:
Smooth muscle Location - muscle in the walls of hollow organs - intrinsic eye muscles
Characteristics - small and spindle shaped, often arranged in sheets - single, involuntary, fusiform, uninucleated muscle - no striations and no sarcomeres - speed of contraction slow and do not tire easily - rhythmic contractions - lack elaborate connective tissue coverings - contract for extended periods at low energy cost and without fatigue
peristalsis:
- circular layer:
- longitudinal layer:
Cardiac muscleLocation: found only in the heart Characteristics: branching chains of uninucleated or binucleated cells, striated with intercalated discs, involuntary, slow rate of rhythmic contractions
THE MUSCULAR SYSTEM
TERMINOLOGY1). Insertion -
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2). Origin -
3). Flexor -
4). Extensor -
5). Adductor -
6). Abductor -
8). Levator -
9). Depressor -
10). Dilator -
Sites for intramuscular injections
1). Deltoid2). Gluteus maximus
Principal Skeletal Muscles
A. Axial muscle group - head, neck, face and trunk musclesB. Appendicular muscle group - extremity muscles
C. 656 muscles in the human body - 327 are antagonistic muscles
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- unpaired muscles 1. orbicularis oris 2. diaphragm
Important muscle groups
A. Hamstring B. Quadriceps femoris group 1. Biceps femoris 1. Rectus femoris 2. Semitendinosus 2. Vastus lateralis 3. Semimembranous 3. Vastus medialis
4. Vastus intermedius
NAMING SKELETAL MUSCLES1). Location:
ex. temporalis, intercostals
2). Shape:
ex. deltoid, trapezius
3). Relative size: maximus -
minimus -
longus -
brevis -
4). Direction of muscle fibers:
rectus -
transversus -
oblique -
5). Number of origins:
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biceps -
triceps -
quadriceps -
6). Origin and/or insertion:
ex. sternocleidomastoid
7). Action of muscle:
FUNDAMENTALS OF THE NERVOUS SYSTEM&
NERVOUS TISSUE
COMPONENTS1). Brain
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2). Spinal cord3). Nerves: spinal nerves cranial nerves
FUNCTIONS1). Coordination and integration (CONTROL, Along with what other system?)
2). Communication:
3). Nerve impulses:
4). Regulating and maintaining homeostasis
HOW THE NERVOUS SYSTEM WORKS1). Sensory input:
2). Integration:
3). Motor output:
Faster acting and more complex than the Endocrine System, but its effects tend not to last as long.
Most highly organized system of the human body!
ORGANIZATION OF THE NERVOUS SYSTEM
A. ANATOMICAL 1. Central Nervous System (CNS) a. Brain & spinal cord b. Control center for the entire system and integration
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2. Peripheral Nervous System (PNS) a. 12 pairs of cranial nerves b. 31 pairs of spinal nerves c. Major Function:
B. FUNCTIONAL (Physiological) 1. Sensory (afferent) Division a. Somatic & visceral sensory neurons b. Function:
2. Motor (Efferent) Division a. Motor neurons b. Function:
C. SUBDIVISIONS OF THE MOTOR DIVISION 1. Somatic Nervous System (SNS) a. conveys information from the CNS to skeletal muscles b. voluntary, conscious control 2. Autonomic Nervous System (ANS) a. conveys information from the CNS to smooth muscles, cardiac muscle, and glands b. involuntary, without conscious control
Two Major Divisions of the ANS a. Parasympathetic:
b. Sympathetic: NERVOUS TISSUE HISTOLOGY
1). Extracellular space - < 20%
2). Structural and functional units called neurons - amitotic - billions!
3). Supporting cells (Neuroglial cells)
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- small, nonexcitable cells, surround and wrap neurons - assist, segregate and insulate neurons - Does the nervous system have more neurons or more neuroglial cells?
- mitotic - gliomas:
Types of Supporting CellsA. CNS Neuroglial Cells 1. Astrocyte:
2. Microglia:
3. Ependymal cells:
4. Oligodendrocytes:
B. PNS Neuroglial Cells 1. Schwann cells:
2. Satellite cells:
ANATOMY OF A NEURON- large complex cells- highly specialized cells which conduct messages- extreme longevity (over 100 years)- high metabolic rate
STRUCTURE1). Cell body: contains a nucleus, nucleolus, cytoplasm - nissl bodies:
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- NO CENTRIOLES!
- perikaryon (soma):
a. nuclei:
b. ganglia:
2). Neuron processes - tracts:
- nerves: a. Dendrites: carries impluses toward the cell body b. Axon: carries impluses away from the cell body
Axon PartsAxon collateral:
Axonal terminals:
Telodendria:
Myelin sheath:
Neurilemma - specialized covering - speeds up the nerve impulse - protects axon (myelin = fatty substance = white matter)Nodes of Ranvier:
Axon hillock:
Nerve fibers:
MYELINATED VS UNMYELINATEDA. Myelinated 1. PNS: Schwann cells -
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2. CNS: Oligodendrocytes - may coil around as many as 60 different axons at the same time - no neurilemma - white matter
B. Unmyelinated 1. PNS: single schwann cell encloses 15 or more axons, but no coiling
2. CNS: Oligodendrocytes embrace but do not wrap - Gray matter: unmyelinated + cell bodies
CLASSIFICATION OF NEURONS
A. Structure 1. Anaxonic:
2. Multipolar:
3. Bipolar:
4. Unipolar:
B. Physiological 1. Sensory neurons (Afferent): carry impulses toward spinal cord and brain
2. Motor neurons (Efferent): carry impulses from the brain and spinal cord to the muscles and glands
3. Interneuron (Association): carry impulses from one neuron to another inside central nervous system
NEUROPHYSIOLOGYIrritability:
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Conductivity:
Sodium-potassium pump:
1). Resting potential: inside of nerve is - outside of nerve is + "polarized"
2). Loss of polarization is called depolarization
3). Action potential: nerve impulse (reversal)
- all-or-none response:
- threshold stimulus:
- propagated:
4). Repolarized: resting potential restored
- Synapse: where impulse goes from one cell to the next cell a. Axodendritic synapse:
b. Axosomatic synapse:
c. Neuromuscular junctions:
d. Neuroglandular junctions:
Two varities of synapses 1). Electrical:
2). Chemical: - Synaptic cleft: the space between the two cells
- Synaptic vesicles:
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- Presynaptic neuron:
- Postsynaptic neuron:
- Neurotransmitters: chemical substance that allows the impulses to go from axon to dendrite or effector - EXAMPLES: Acetylcholine Epinephrine & Norepinephrine Dopamine Serotonin Histamine
- Neuropeptides: pain-killing neurotransmitters - EXAMPLES: Endorphines Enkephalins
NEURAL INTEGRATIONTypes of circuits:1. Diverging:
2. Converging:
3. Reverberating:
THE CENTRAL NERVOUS SYSTEM
COMPONENTS: Brain & Spinal CordLOCATION:
Cephalization:
Protection of The CNS1. Skull2. Meninges (Meninx):
- cover & protects - protect blood vessels and enclose venous sinuses
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- contain cerebral spinal fluid - forms partitions within the skull
a. Dura mater - leathery, double membrane, outer layer of the brain with the outer membrane attached to the skull - in places attaches brain to skull to prevent excessive movement
b. Arachnoid mater - middle layer, loosely covers brain - separated from dura mater by subdural space - between arachnoid mater and pia mater is the subarachnoid space - contains the largest blood vessels serving the brain
c. Pia mater - inner layer, composed of delicate connective tissue with many small blood vessels - clings tightly to the brain
3. Cerebrospinal fluid - found in 4 ventricles (2 lateral, third, fourth) - liquid cushion, gives buoyancy to CNS organs - floats the jelly-like brain - protection from blows and trauma - helps nourish the brain - derived from blood plasma but with a different composition - formed from the choroid plexuses
THE BRAIN- weighs ~ 3.5 lbs (1600 g)
A. FOUR MAJOR PARTS OF THE BRAIN: - Cerebrum: Cerebral hemispheres - Cerebellum - Diencephalon: Thalamus, Hypothalmus, Epithalamus - Brain stem: Midbrain, Pons, Medulla oblongata
B. VENTRICLES: hollow chambers lined with ependymal cells 1. Lateral: two, C-shaped, 1 in each hemisphere of cerebrum 2. Third: in the diencephalon, connected to 2 laterals by the interventricular foramen 3. Fourth: dorsal to the pons and superior to medulla oblongata
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- connected to third via the cerebral aqueduct (which runs through the midbrain) - continuous with central canal of spinal cord
Brain StructureA. Cerebrum; largest, divided into two hemispheres, ~ 83% of total brain weight Functions: motor functions, speech, sensory center, visual center, auditory center, olfactory center, conscious thought, judgment, memory, reasoning, will power.
- fissures: deep grooves - sulci: shallow grooves - gyri: convolutions (elevated ridges) - longitudinal fissure:
- transverse fissure:3 Basic Regions of the Cerebrum
1. Cortex:
- 2-4 mm thick - ~ 40% of total brain mass
2. White matter: - communication between cerebral areas and cerebral cortex and lower CNS centers - mainly myelinated fibers bundled into large tracts
3. Basal Nuclei: - gray matter areas located deep within the white matter of the cerebral hemispheres - may play role in motor control??
Generalization about the Cerebrum1. 3 kinds of functional areas a. motor:
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b. sensory:
c. association:
2. Each hemisphere acts contralateral
3. Lateralization of hemispheres "split brain concept" a. ~ 90% of people are left cerebral dominate - left hemisphere dominate: mathematical abilities, logic - right hemisphere dominate: visual-spatial skills, intuition, emotion, art and music appreciation - most are right handed
b. ~ 10% of people are right cerebral dominate or neither
Dyslexia: reading disorder, intelligent people reverse order of letters, syllables, numbers - has been attributed in some cases to a lack of cerebral dominance
4. No functional area acts alone!
B. Diencephalon: composed of three major regions - surrounded by the cerebral hemispheres, enclose the third ventricle
1. Thalamus: relay station for incoming and outgoing nerve impulses, sorts out information - mediates sensations, motor activities, cortical arousal, memory
2. Hypothalamus: Autonomic nervous control (regulates parasympathetic and sympathetic systems of ANS)
- Cardiovascular control, temperature control, appetite control, water balance, gastrointestinal control, emotional state, sleep control, thirst, Main Visceral Control Center
- An endocrine gland: Produces ADH & Oxytocin, regulates
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hormonal output of anterior pituitary gland
3. Epithalamus: dorsal most part of diencephalon - pineal gland (body): extends from epithalamus, produces melatonin: mood & sleep/wake cycles
- Choroid plexus:
4. Limbic system: Emotional brain
Mammary bodies: olfactory relay stations
C. Cerebellum: 2 hemispheres connected by the vermis, tree-like pattern called Arbor vitae ("tree of life")
- maintenance of balance, muscle tone, and coordination of skeletal muscle contractions, posture - process information from proprioceptors:
D. The Brain stem; 3 regions - responsible for automatic behaviors necessary for survival - 10 of 12 pairs of cranial nerves 1. Midbrain: between the pons and the diencephalon - conduction pathway between higher and lower brain functions - visual and auditory control centers - motor centers
2. Pons: respiratory center, relay between medulla oblongata and cerebrum, relay information from cerebrum to cerebellum 3. Medulla oblongata: vasoconstrictor center, respiratory center, cardiac center, sensory relay to cerebellum, centers for controlling: vomiting, coughing, hiccuping, swallowing, and sneezing
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- decussation:
4. Reticular formation: Maintains cerebral cortical alertness (reticular activating system), Helps regulate skeletal & visceral muscle activity.
THE SPINAL CORD
- Begins at foramen magnum and extends to the level of the first lumbar vertebra- Lies within the vertebral column- Major reflex center - Two-way conduction pathway to and from the brain- 31 pairs of spinal nerves- divided into right and left halves by the anterior median fissure & the posterior median sulcus
Spinal Cord Enlargements1). Cervical:
2). Lumbar:Cauda equina:
conus medullaris:
filum terminale:
Gray matter - appears in the shape of a "butterfly", called commissure
White matter - surrounds gray matter, called funiculi 1. sensory areas 2. motor areas 3. ascending and descending tracts a. ascending: (sensory) conduct sensory impulses upward through chains of 2 or 3 successive neurons to various parts of the brain
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b. descending: (motor) conduct motor impulses from brain to spinal cord. Two different groups: Pyramidal:
Others:
REFLEX ARC: unconscious and involuntaryIs the brain involved?
Steps1. receive stimulus2. sensory receptors3. sensory neurons4. interneuron5. motor neuron6. effectors (muscles, glands)
THE PERIPHERIAL NERVOUS SYSTEM & REFLEX ACTIVITY
Allows the CNS to receive information and to carry out its decisions!
Components: 1. Sensory receptors: specialized to respond to changes in the environment "stimuli" a. Sensation:
b. Perception:
c. Adaptation:
2. Perpherial nerves and their associated ganglia3. Motor endings
Three types of Sensory Receptors Named Based on Location
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1. Exteroceptors:
2. Interoceptors (visceroceptors):
3. Proprioceptors:
Types of Receptors Named Based on Stimulus1). Mechanoreceptors:
2). Thermoreceptors:
3). Photoreceptors:
4). Chemoreceptors:
5). Nociceptors:
Types of Receptors Named Based on Structure1). Simple: - general senses: temperature, pain, touch, pressure a. Free nerve endings:
b. Merkel discs:
c. Root hair plexuses:
d. Meissner's corpuscles:
e. Krause's end bulbs:
f. Pacinian corpuscles:
g. Ruffini's corpuscles:
2). Complex: - Special senses: eyes, ears, nose, tongue
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CRANIAL NERVES1). Olfactory: smell
2). Optic: vision
3). Oculomotor: moves the eyeball
4). Trochlear: eye movement
5). Abducens: eye movement
6). Trigeminal: sensory fibers to the face, motor fibers for chewing
7). Facial: facial expressions
8). Vestibulocochlear: hearing & balance
9). Glossopharyngeal: tongue & pharynx
10). Vagus: internal organs
11). Accessory: neck & back muscles
12). Hypoglossal: tongue muscles
SPINAL NERVES- 31 pairs a. 8 prs = cervical b. 12 prs = thoracic c. 5 prs = lumbar d. 5 prs = sacral e. 1 pr = coccygeal
Dermatomes:
Reflex ActivityA. Somatic reflexes: activate skeletal muscle
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B. Autonomic (Visceral) reflexes: activate cardiac and smooth muscles or glands
THE AUTONOMIC NERVOUS SYSTEM
System of motor neurons that innervate cardiac and smooth muscles and glands.
Also referred to as:Involuntary nervous system - subconscious controlGeneral visceral motor system - location of most of its effectors
Divisions of the ANS1). Parasympathetic:
2). Sympathetic:
Differences Between The ANS & SNSSNS ANS
1). Effectors skeletal muscles cardiac & smooth muscles and
glands
2). Efferent Pathways cell bodies located preganglionic
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in CNS, Axons neuron:extend to skeletalmuscles, motor postganglionic fibers thick, heavily neuron:myelinated
lightly myelinatyed:preganglionic neuronnon-myelinated:postganglionic neuronmotor fibers thin
3). Target responses to acetylcholine acetylcholine neurotransmitters excitatory norepinephrine
either excitatory orinhibitatory
Higher brain centers regulate and coordinate both SNS & ANS motor activities!
THE DIVISIONS OF THE ANS
The parasympathetic and the sympathetic divisions generally serve the same visceral organs but cause essentially opposite effects!
A. THE PARASYMPATHETIC DIVISION - most active in non-stressful situations, maintenance activities - "resting & digesting", elimination of feces & urine - concerned with keeping body energy use as low as possible - fibers emerge from the brain and sacral region of the spinal cord: therefore also called the craniosacral division - long preganglionic and short postganglionic fibers - most ganglia located in the visceral effector organs - causes vasodilation of blood vessels in external genitalia "erection of male penis" & "erection of female clitoris" during sexual excitement
B. THE SYMPATHETIC DIVISION - "flight-or-fight" system - mobilizes body to meet emergencies (fear, exercise, rage), enables
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the body to cope rapidly and vigorously with situations that threaten homeostasis - fibers emerge from the thoracic & lumbar regions of the spinal cord: also called the thoracolumbar division - short preganglionic and long postganglionic fibers - most ganglia located close to the spinal cord - more complex than the parasympathetic, partly because it innervates more organs - sweat glands, arrector pili muscles, all arteries and veins - causes ejaculation of semen by male and peristalsis of female's vagina - help regulate body temperature, activate the sweat glands to help cool the body - stimulate kidneys to release renin - promotes an increase in blood pressure - effects tend to be much longer-lasting than those of parasympathetic
NEUROTRANSMITTER RECEPTORSA. CHOLINERGIC RECEPTORS - mimic acetylcholine's effects 1. Nicotinic receptors:
2. Muscarinic receptors:
B. ADRENERGIC RECEPTORS - norepinephrine and epinephrine 1. Alpha receptors:
2. Beta receptors:
Knowing the locations of the different receptor sites is very importantclinically, because it allows specific drugs to be prescribed to obtain the
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desired blocking or stimulatory effects on selected target organs!
CONTROL OF AUTONOMIC FUNCTIONING1). Reflex activity: spinal cord and Brain stem centers
2). Hypothalamic integration centers: autonomic, somatc, endocrine responses
3). Cortical centers: influence autonomic functioning via connections with the limbic system
NEURAL INTEGRATION
All activities of the nervous system go on simultaneously!The Somatosensory System
- deals with reception in the body wall and limbs- receives imputs from exteroceptors, proprioceptors, interoceptors- consists of three primary levels of neural integration 1). Receptor level 2). Circuit level 3). Perceptual level
A. The Receptor Level - sensory receptors respond to energetic stimuli: sound, mechanical, chemical, light, etc. (rest of nervous system responds to chemicals in the form of neurotransmitters) - translate stimulus into a nerve impulse, this conversion of stimulus energy to electrical energy is called transduction
B. The Circuit Level - sensory fibers - carry impulses from cutaneous receptors and proprioceptors to the spinal cord
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- branch as they enter the spinal cord 1. some branches - spinal reflexes - motor activities 2. two major ascending routes: relay information to the brain for three purposes; perception, arousal, motor control
a. nonspecific ascending pathways: most transmit pain and temperature impulses, some transmit impulses for light touch, pressure, or joint information - "itch"
b. specific ascending pathways: chiefly concerned with percise straight-through transmission of inputs from a single type of sensory receptors. - discriminative touch, pressure, vibration, limb & joint position - nonspecific & specific pathways are parallel pathways which are activated simultaneously a. add richness to our perceptions - allows the same information to be handled in different ways b. provide insurance
C. The Perceptual Level - involves awareness of stimuli and discrimination of their characteristics - we can act or not act on the information 1. sensory perception:
2. magnitude estimation:
3. spatial discrimination:
4. feature abstraction:
5. quality discrimination:
6. pattern recognition:
Motor Integration- effectors (muscle fibers)- descending efferent circuits- motor behaviorThree Levels of Motor Control
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A. Segmental Level - spinal cord circuitry: controls reflexes and fixed action patterns
B. Projection Level - descending fibers in the spinal cord
C. Programs/Instructions Level - cerebullum: proprioceptor, tactile, equilibrium, visual inputs, feedback needed for rapid correction of “errors” in motor activity
- basal nuclei: complex aspects of motor control
Brain Waves- resulting patterns of neuronal electrical activity- EEG (electroencephalogram):A. Alpha waves - in most cases: a calm, relaxed state of wakefulness, "ideling"
B. Beta waves - awake, mentally alert, when we concentrate on some problem or visual stimulus
C. Theta waves - early stages of sleep, abnormal in awake adults
D. Delta waves - seen during deep sleep and when the reticular activating system is damped, such as during anesthesia
Amplitude: number of neurons firing together in synchrony
Brain waves change with: a. age b. sensory stimuli c. brain disease d. chemical state of the body
Sleep & Sleep-Awake CyclesSleep:
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Coma:
Reticular Activating System (RAS):
Stages of Sleep1). Nonrapid eye movement (NREM):
2). Rapid eye movement (REM):
Higher Mental FunctionsConsciousness:
Memory:
a. short term memory:
b. long term memory:
c. fact memory:
Language:
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THE SPECIAL SENSES
TWO MAJOR TYPES OF SENSES1). General senses: most are modified dendrites of sensory neurons a. touch b. pain c. temperature: hot/cold d. pressure
2). Special senses: Where do you find them? a. Chemoreceptors:
- taste buds: taste - olfactory receptors: smell
b. Photoreceptors:
- eyes: sight
c. Mechanoreceptors:
- ears: hearing & balance
Projection:
TASTE
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Taste buds: differences in taste buds are not absolute, most taste buds responds to 2 or 3 or all four taste qualities
1). Salty:
2). Sweet:
3). Sour:
4). Bitter:
STRUCTURE of a TASTE BUDA. Papillae: - fungiform:
- Circumvallate:
B. Globular taste bud consists of 40 - 60 epithelial cells 3 major types 1. supporting cells:
2. taste cells (gustatory):
3. basal cells:
C. Taste pore:
D. Gustatory hairs:
SMELLOlfaction: detects chemicals in solution smell organ - a yellow-tinged patch of pseudostratified epithelium called olfactory epithelium.
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- contain millions of bowling-pin shaped olfactory receptor cells (bipolar neurons). - olfactory hairs located on olfactory receptor cells and covered with a mucus layer.
THE EYE- about 1" in diameter- lies in orbital socket of skull- 3 dimensional vision: length, width, depth = stereoscopic vision.- protected by: bone, fat pad, and accessory structures Accessory Structures: 1. Eyebrows & eyelashes:
2. Eyelids:
3. Conjunctiva:
4. Eye muscles:
5. Lacrimal Apparatus: tears - mucus, antibodies, lysozyme
lacrimal gland è ducts è eyelids è inferior/superior lacrimal canals (caniliculi)
è lacrimal sac è nasolacrimal duct è nasal cavity
PARTS OF THE EYE & THEIR FUNCTIONS1). Sclera: outer layer, white, maintains shape & protection
2). Cornea: transparent anterior part of sclerotic coat, permits light rays to pass through - plays a role in bending light rays
3). Choroid coat: contains blood vessels, non-reflective brown pigment (melanocytes), middle layer of eye, prevents light
reflection within eye, absorbs light
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4). Ciliary body: - ciliary muscle: - suspensory ligament:
5). Pupil: opening
6). Iris: colored part of eye due to amount of melanin, controls amount of light passing through lens
7). Lens: located behind iris and pupil, elastic, disk-shaped structure, bends light rays
- Anterior cavity*: filled with aqueous humor - in front of lens a. Anterior Chamber:
b. Posterior Chamber:
- Posterior cavity*: filled with vitreous humor - behind lens
* = help in maintaining shape and bending light rays
8). Retina: inner most layer of eye, light sensitive layer, image formed - rods: black & white vision - cones: color vision
Farsightedness = Hyperopia:
Nearsightedness = Myopia:
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9). Fovea centralis:
- macula lutea:
THE EARDivided into three regions1). Outer ear (external ear) a. pinna (auricle): funnels sound waves to tympanic membrane b. external auditory meatus: canal leading to tympanic membrane - lined with ceruminous glands c. tympanic membrane (eardrum): separates outer ear from middle ear
2). Middle ear a. tympanic cavity: small airfilled cavity between the tympanic membrane and the oval & round windows, lined with mucous b. eustachian tube (auditory tube): equalizes pressure - tympanic cavity to nasopharynx c. ear ossicles: transmit sound waves from tympanic membrane to inner ear - malleus (hammer) - incus (anvil) - stapes (stirrup) 3). Inner ear (Also called Labyrinth) - Bony labyrinth: perilymph
- Membranous labyrinth: endolymph
a. Cochlea: spiral-shaped, contains the cochlear duct which is
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filled with fluid that vibrates the organ of corti b. Semicircular canals: contain the ampulla - which house the crista ampullaris, site for dynamic equilbrium (head moving). c. Vestibule: contains the utricle & saccule which house the maculae, receptor site for static equilbrium (head not moving)
d. Scala vestibuli: - vestibular membrane
e. Scala tympani: - basilar membrane
f. Tectorial membrane:
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