Human Biology – Applicable to Your LIFE!!!

Human Biology – Applicable to Your LIFE!!!

What is Life Anyway?What is Life Anyway?

What does it mean to you to be alive?From a biological perspective, what must you be

able to do to be considered living?

The Unity of Life – Starts w/DNA(Section 1.4)

The Unity of Life – Starts w/DNA(Section 1.4)

Living Things . . . Are highly ordered Are made up molecules Contain DNA Are composed of cells Can utilize energy Regulate their environment Respond and adapt to their

environment Grow and Develop Reproduce Evolves or changes over time

The Hierarchy of Life – Levels of Organization

The Hierarchy of Life – Levels of Organization

1. ChemicalsAtoms & Molecules

2. CellsComposed of chemicals and

organelles3. Tissues

Epithelial, connective, muscle, nervous

5. Organs Two or more tissues working

together6. Organ systems

11 systems total7. Organism

So, where do anatomy & physiology come in . . . So, where do anatomy & physiology come in . . .

Anatomy – Structure of the body1. Systemic – approach in this textbook2. Regional – approach for medical/dental school3. Surface – approach used to diagnose disease

Anatomical ImagingPhysiology –Function of the body

Understand and predict the body’s response to stimuli Understand how body maintains homeostasis

What is Homeostasis?

11 major organ systems11 major organ systems1. Integumentary2. Skeletal3. Muscular4. Nervous5. Endocrine6. Cardiovascular7. Lymphatic8. Respiratory9. Digestive10. Urinary11. Reproductive

homeostasishomeostasis

Homeostasis – existence and maintenance of a relatively constant environment within the body – a dynamic equilibrium

1. Negative feedback – maintain homeostasis – any deviation from a normal value is diminished or resisted

2. Positive feedback – not homeostatic and are rare in healthy humans – when a deviation from the norm occurs, it is increased by positive feedback. One of the few examples of a normally occurring positive feedback mechanism is the birth process

Terminology and the body plan

Terminology and the body planAll directional terms apply to anatomical position

Etymology – Word Origin (mostly Latin and Greek)Superior/Inferior – above/belowAnterior/ventral – in front ofPosterior/dorsal - behindProximal/Distal – closer to the center/further from centerLateral/Medial – to the side/to the centerSuperficial/Deep – on the surface/deep

TABLE 1.1 – Page 10

planesplanesFOR THE BODY

Sagittal – vertical planeMidsagittal – in the middle to

divide rt/ltTransverse/horizontalFrontal/coronal – vertical, but

ant/post.FOR ORGANS

Longitudinal – verticalTransverse/cross – Oblique – comes down at an

angle

Body regionsBody regions

Upper limb Arm – shoulder to elbowForearm – elbow to wrist

Lower limb Thigh – hip to knee Leg – knee to ankle

Central region Head, neck, trunk

Trunk – further subdivided into> Thorax, abdomen, pelvis

Body cavitiesBody cavities

3 major trunk cavities 1. Thoracic cavity – surrounded by rib cage,

bounded by diaphragm, separated into right and left parts by a mediastinum

What is the Mediastinum? Name for the compartment that divides the thoracic cavity (with the lungs on either side) and structure that contains the heart, thymus gland, tracheal, esophagus, etc

Body cavities, continuedBody cavities, continued2. Abdominal cavity – bounded

by the abdominal muscles and contains the stomach, intestines, liver, spleen, pancreas, and kidneys

3. Pelvic cavity – enclosed by the bones of the pelvis – contains urinary bladder, part of the large intestine, internal reproductive organs

The abdominal and pelvic cavities are not physically separated and are sometimes called the abdominopelvic cavity

Serous membranesSerous membranes

Serous membranes line the trunk cavities and cover the organs of the trunk cavities

These double-walled membranes contain:1. Visceral membrane2. Cavity3. Parietal membrane

Locations of serous membranes

Locations of serous membranes

Thoracic cavity1. Pericardial cavity and membranes2. Left and right pleural cavities and membranes

Abdominopelvic cavity1. Peritoneal cavity and membrane

MesenteryRetroperitoneal organs

Peritoneum w/microvilliPeritoneum w/microvilli