Organisms and Populations

Chapters 27-57III. Organisms and Populations (50%)

A. Diversity of Organisms (8%) 1.Evolutionary patterns 2.Survey of the diversity of life 3.Phylogenetic classification 4.Evolutionary relationships

B. Structure and Function of Plants and Animals (32%)1.Reproduction, growth, and development 2.Structural, physiological, and behavioral adaptations 3.Response to the environment

C. Ecology (10%)1.Population dynamics 2.Communities and ecosystems 3.Global issues

Survey of Diversity of Life• 6 Kingdoms

– Prokaryotes (Bacteria and Archae)• Both unicell, small, circular chromos, binary fission, no compartments, simple flagella, diverse

metabolism• Diff membranes, cell walls, ribosomes (Arch~euk), introns

– Peptidoglycan (G+, G-), endospores– Photoauto, chemoauto, photohetero, chemohetero– Good vs. bad

– Protists (eukary hard to classify)• Unicell or multi, some cell walls (silica), schizogony, flagella, cilia, contractile vacuole, eyespot,

sporangium– Plasmodium, Chlorophyta (Chlamydomonas)

– Plants (eukary, multi, auto, cellulose)• Adaptations to land to avoid dessication (vascular, cuticle, stomata), alternation of generation life cycle

– Diploid sporophyte makes spores through meiosis, mitosis forms multi-cell haploid gametophyte, makes gametes that fuse

– Mosses, Ferns, Gymnosperms, Angiosperms– Fungi (eukary, multi, extracell hetero, chitin)

• Monokaryotic vs dikaryotic (homo or hetero)– Alternation of generations, yeast, lichens, mycorrhizae, parasites/pathogens

– Animals (eukaryo, multi, hetero, motile)• Tissues, symmetry (bilateral = 3layers), body cavity, deutersome development, segmentation

Animal Diversity• Porifera (sponges)

– Larvae free swimming, adults sessile– Choanocytes bring in water for filter feeding– Sexual or Fragmentation for reproduct

• Cnidarians (jellyfish - polyp or medusa)– Distinct tissues, stinging nematocyst, nerve net

• Platyhelminthes (flatworms -- tapeworms)– Bilateral, incomplete gut, hermaphrodite

• Nematodes (pseudocoelomates - roundworms)– Hydrostatic skeleton b/c pseudo

• Mollusk (snails, clams, oysters, octopuses)– COELOM (more variety, larger size)

• Annelid worms (earthworms, leeches)– Repeated segments, specialized segments (differentiation), brain, systems

• Arthropods (crustaceans, beetles, flies, spiders)– Jointed appendages, exoskeleton, sensory, but dorsal brain, advanced systems

• Echinoderms (starfish, urchins)– Deuterosome, endoskeleton, nerve ring

• Chordates (vertebral column, head, neural crest, organs, endoskeleton)– Cartilage Fish, Bony Fish, Amphibians, Reptiles, Birds, Mammals

Mammalian Bodies• Epithelial Tissue, Connective, Muscle, Nerve, Skeletal

System• Muscles

– Muscle fibers-myofibrils-myofilaments-sarcomere• Sliding filament theory (thin actin slides in towards myosin)• Troponin holds tropomyosin preventing mysoin heads from

binding to actin• Ca++ removes troponin, loosening tropomyosin, myosin binds to

actin, shifts, releaing ADP/Pi, ATP added to release– ATP also needed to pump Ca++ back into SR

» Glucose and glycogen– Nerve cell transduces signal, releases Acetycholine to transduce

muscle signal• Increased blood flow removes lactic acid, provides O2

Digestion (regulation by release of enzymes)

• Herbi-, Carni-, Omni- (teeth)• Saliva and chewing (enzyme and mechanical)

– Swallow close trachea and larynx

• Esophagus (tubes and sphincter)• Stomach (storage, acid, digest only proteins, sphincter)• Small intest. (chyme, villi, microvilli, brush border, absorbtion)• Pancreas (insulin, glucagon, inactive enzymes, bicarbonate)• Liver (receives blood, metabolizes toxins, waste bile pigments, bile salts)• Gallbladder (stores bile salts which break down fats)• Large intestine (remove water, compact waste)

Circulatory and Respiration

• Comparative structures• Blood pressure• Electrical signals from SA/AV node

– PQRST wave

• Gas exchange (concentration, area, distance, aqueous (dissolves)

• Negative pressure, branching, CO2 levels make acidic (unload more O2)

Nervous System

• Structure of a nerve cells• Resting potential determine by Na+/K+ pump

– Ligand gated channels open for ion flow (in!) - threshold• Acetycholine, norepinephrine, dopamine (mvmt), serotonin (emotion)

• Evolution of structures• CNS vs PNS (somatic/autonomic (sympa/parasympa)• Reflex• Sensory

– Stimulation (receptors), transduction, transmission, interpretation– PICK THREE and know how structure works (ear, lateral line, eye)

Endocrine• Hormone is regulatory chemical,

only target cells respond– Polypeptides, Glycoproteins, Amines,

Steroids (enter cells?)• Nervous (sensing) and endocrine

(response)– Posterior Pituitary (ADH, oxytocin)– Anterior (thyroidSH, GH, FSH, LH,

prolactin)– Adrenal medulla secretes epinephrine

to act on smooth muscle, cardiac muscle, blood vessels to initiate stress response

Immune• MHC IDs your body vs

antigen• WBC

– Non-specific Defending (macro, neutro, natural killer)

• Macrophage presents to T helper cell

– Specific killers (Helper, Cytotoxic, Memory, Suppressor T cells)

– Specific markers (Memory and Plasma B cells)

– MAKE ANTIBODIES!!! To tag invader

• Protein processing makes variable

IMPT for immunity -- reason for vaccines (dead/weak/ still respond)

Homeostasis

• Temperature, glucose, blood volume• Evolution of structures• Nitrogenous waste• Kidneys

– Nephrons• Blood vessels form glomerulus, ALL filtrate enters Bowman’s capsule into

tubes (except cells and proteins), must put water back• Actively pump Na+ ions back, Cl-, water will follow• Collect in duct, bladder

– ADH - too many ions? - produced by hypothalamus, secreted by posterior pituitary gland, conserve water

– Aldosterone -- SIMILAR?– ANH = antagonist

Reproduction

• FSH and LH = ovulation and growth of uterine lining

• Estradiol and progesterone inhibit FSH and LH so no more ovulation– Fetus will continue to

produce estradiol and progesterone

Development

• Embryo, cleavage, gastrulation, neuralation, organogenesis, morphogenesis

• Ontogeny recapitulates phylogeny