Please enable JavaScript.
Coggle requires JavaScript to display documents.
Circulation and Gas Exchange/ Osmoregulation and Excretion (Respiratory…
Circulation and Gas Exchange/ Osmoregulation and Excretion
Types of Circulatory Systems
Open
Circulatory fluid (
hemolymph
) is just hanging out in the body cavity
Clams, grasshoppers
Closed
Double pump
SIMULTANEOUSLY:
Deoxygenated blood from heart -> lungs -> back to heart
Oxygenated blood from heart -> body systems -> back to heart
Single pump (circulation)
Deoxygenated blood in heart-> gills -> oxygenated blood to body -> deoxygenated blood back to heart
Blood is confined to vessels-separate from interstitial fluid
Earthworms, squids, all vertebrates
Circulatory Structures
Lymph Stuff
Lymphatic system recovers fluid that's leaked out of the capillaries
Lymphatic system dumps fluid into cardiovascular system through veins
Movement of lymph: valves, skeletal muscle, vessel contraction
Edema- fluid accumulation
Lymph nodes- part of body defense
Vessels- all have a lumen lined with endothelium
Veins
Thinner walls than arteries
Valves- keep things going to right way
Arteries
Thick walls (high blood pressure)- endothelium, smooth muscle, connective tissue
Strong, elastic
Capillaries
Smallest
GAS EXCHANGE
Thin walls- endothelium and basal lamina
Hearts
Amphibians- 3 chambers (2 atria, 1 ventricle); oxygenated and deoxygenated blood mix, less efficient
Fish- 2 chambers (1 atrium, 1 ventricle); significant blood pressure drop as blood flows through the capillary beds
Mammals- 4 chambers (2 atria, 2 ventricles)
Blood
Plasma- liquid matrix
Water- solvent
Ions (Na, K, Calcium, Mg, Cl, HCO)- osmotic balance, pH buffering
Proteins (albumin, antibodies, apolipoproteins, fibrinogen)- lipid transport, clotting, immunity
Cells
Immune Cells- basophils, lymphocytes, eosinophils, neutrophils, monocytes- immunity and defense
Erythrocytes- transport of O2 and some CO2
Blood Pressure
Normal: 120/80
Stage 1 Hypertension: 140/90
Stage 2 Hypertension: 160/100
Atherosclerosis- accumulation of fatty deposits- leads to hypertension
Respiratory Structures
Partial Pressure- pressure exerted by a gas in a mixture of gasses
Gills
Folds that are suspended in water
Ventilation- maintains partial pressure needed for gas exchange
Countercurrent exchange- fluids in opposite directions- more efficient
Tracheal system
Network of air tubes through body- takes O2 directly to tissues
Usually highly adapted for energy needs of organism
Lungs
Divided into numerous pockets
Localized- circulatory system necessary for taking O2 to body
Positive pressure- forced air flow
Negative pressure-
pulling
air into lungs (low pressure area)
Osmoregulation
- how animals control balance of solutes and water gain/ loss
Osmolarity- unit for measurement of solute concentration
Mechanisms of osmoregulation
Osmoconformer
Isoosmotic with surroundings- do not gain/ lose water
MARINE ANIMALS- rely on active solute transport
Salt in from water/ food, water in from drinking/ food
Salt out through gills/ urine, water out through urine/ gills
Usually live in water with stable composition
Osmoregulator
Control internal osmolarity independent of environment
Environments not suited for osmoconformers (fresh water, terrestrial habitats)
Gain salt from gills, gain water in food/ gills
Lose salt in urine, lose lots of water in urine
Freshwater animals- rely on lots of diluted urine for water balance
Excretion
Excretory Systems
Protonephridia- flatworms, most simple
Metanephridia- annelids
Malpighian Tubules- insects, terrestrial arthropods; NO FILTRATION
Forms of Nitrogenous Waste
Ammonia- common in aquatic species; readily diffuse through membranes;
Urea- product of metabolic cycle; very low toxicity but high energy cost (going from ammonia to urea); mammals, most amphibians, sharks
Uric Acid- insects, reptiles, birds; does NOT readily dissolve in water= can be excreted as a semisolid with little water loss; VERY HIGH energy cost
Kidneys
Nephron
Proximal tubule- reabsorption of stuff you want to keep
Descending limb of loop of Henle- aquaporins make epithelium permeable to water; water out
Ascending limb of loop of Henle- NO water channels, reclaiming salt- filtrate becomes more dilute
Distal tubule- regulates K and NaCl concentrations; pH regulation
Collecting duct- Processes filtrate into urine & takes it to renal pelvis
Long loops (
juxtamedullary nephrons
) result in concentrated urine (desert mammals)
Shorter loops (
cortical nephrons
) not as good at concentrating urine (freshwater)
ADH- cause more aquaporins, more water reclaimed
RAA System- responds to blood volume/ pressure change by effecting Na reabsorption