many hemoglobin molecules in rbc, heme is place on hemoglobin where oxygen binds

quarternary structure - 4 protein chains

2 beta chains, 2 alpha chains

prosthetic group with Fe in the center

-binding site for oxygen

each time O₂ molecule binds, it increases the affinity for the next O₂ molecule to bind

-oxyhemoglobin forms in lungs but must dissociate in tissues

-when blood oxygen is low, blood is released from the heme group

connective tissue --> smooth muscle tissue --> elastic layer --> endothelial cells

-smooth muscle thick (in comparison with veins) because arteries have to undergo more pressure

one layer of cells thick

-endothelial cells

connective tissue --> smooth muscle --> elastic layer --> endothelium

-thicker connective tissue, in comparison to arteries

-thinner smooth muscle

-collapsed

-thinner elastic layer

movement of blood in veins

valves that prevent back flow

-contracting skeletal muscle around veins help blood make it back to heart

varicose veins

1.diffusion

2. secretion

3. filtration

across endothelial cell (blood to cells or cells to blood)

-oxygen, carbon dioxide, LIPID hormones

vesicles in endothelial cells can pick up materials by endocytosis on one side of the cell, move it across the cell, and expel the materials by exocytosis on the other side

capillary functions: filtration

filtration in the brain, kidneys, liver

in brain, gaps between endothelial cells in capillaries are small, little filtration

in the liver and kidneys, endothelial cells have large spaces between and everything but cells and large proteins can pass between

hydrostatic pressure (BP)

blood pressure?

determining factors of filtration

hydrostatic pressure and osmotic pressure

-ultimately, hydrostatic pressure "wins" and some fluid is lost to interstitial fluid, it enters the lymphatic system and returns to the blood

-an open circulatory system

-like veins but no pressure

have valves and contracting skeletal muscle surrounding it

-substance inside lymph ducts called lymph

-stuff absorbed into ducts due to high blood pressure

thoracic duct and right lymphatic duct

-these both fuse with veins in the shoulders

portal system

four areas where there are portal systems

(deoxygenated?) blood enters a second capillary system before returning to the heart

-liver, kidney, pituitary gland, heat exchange rete

constant internal environment is essential tos urvival of all animals

(pH, salinity, temp, etc.)

1.perturbing factor

2.stimulus deviation from set point

3. sensor constantly monitors conditions

4.integrating center compares conditions to set point

5.effector causes changes to compensate for deviation

6.responses return to set point

negative loop is from 6 back to 4

regulation of body temperature

important for all animals

ectotherms

endotherms

different portions of body maintain different temperatures

think about the picture of the lizard

adaptations for thermoregulation

-surface to volume ratio

small ears --> lose less heat (cold places)

big body --> low SA/vol ratio, less heat loss (cold places)

small body --> high SA/vol ratio, more heat loss (warm places)

behavioral adaptations of thermoregulators

basking

piloerection - feathers stand up, forms like a heat insulator, works like an igloo

done to promote heat loss (to environment)

when you exercise your face gets red, blood vessels near skin dilate and more blood is near the skin and so your face looks more red becuase of the blood thats near the surface

controlled by the Islets of Langerhans

-islets of langerhans causes pancreas to release insulin when the notice high blood sugar

-insulin causes cells to uptake glucose in blood

the balance of uptake and loss of water and dissolved solutes

very important in kidneys

certain solute concentrations in cells

-cells must be osmotically similar to extracellular fluid, but they can have different ions

(isotonic with environment)

-most marine invertebrates

all aquatic animals that maintain their cells at solute conc.'s that are essentially the same as the surrounding water

-jellyfish, flatworms, mollusks

-will burst if they move into a hypotonic environment (fresh/brackish water)

hyper/hypotonic with environment

-virtually all vertebrates and

-all terrestrial organisms

-all freshwater animals

body tissue is always hypertonic to freshwater, but usually hypotonic relative to marine (salt water) animals

since hypertonic, must prevent water from entering the body

does not drink water

solutes pumped in by cells in gills

large volume of dilute urine

problem: water gain by osmosis, solutes lost by diffusion (passive)

body fluids have lower (hypotonic) solute concentration compared to environment, and need to stay that way

-drinks sea water

-problem: water lost by osmosis, solutes gained by diffusion

-solutes pumped out by cells in gills

-very small volume of conentrated urine

fresh water fishes' problem is a)gaining too much water b/c hypertonic to environment and b) losing solutes through diffusion

salt water fishes' problem is a) water lost by osmosis b/c hypotonic and b) gaining to many solutes by diffusion

hagfish: isotonic to sea water

sharks: retain urea, maintain solutes higher than sea water

salmon: switch osmoregulatory strategies (b/c live in saltwater and freshwater throughout their lives)

sea birds: release escess slat through glands

body fluids have higher water concentration than environment

-problem: water loss through evaporation, feces, urine, perspiration

drinking it

eating food

impermeable skin

minimizing water loss during excretion

-vertebrate kidney

do not drink water (b/c there isn't any)

specialized kidneys

no sweating

nocturnal

dry feces

reduce water loss through adaptations in respiratory system

-stand facing sun, reduces exposure

-maintain high body temp during the day, reduces sweating