Chapter 3 Systems Flashcards
(120 cards)
How do platyhelminths and annelids respire?
exchange of gas with the environment, easily diffuse
platyhelminths (flatworms)
annelids (segmented worms)
How do fish respire?
evanginated (outgrowths)
larger surface area
(can be internal or external)
What is the gill cover called?
operculum
How do insects respire?
Tracheae - tubular system lined with chitin
- openings in trachea …
What are the openings in trachea for insects called?
spiracles
Where are chemoreceptors found and what do they do involving respiration?
- medulla oblongata, aorta, carotid arteries
- detect partial pressure of O2 (if low = respirate more)
- detect pH (if acidic = respirate more = increase CO2 dissociated into H+ ions and bicarbonate)
What circulatory systems do insects and molluscs have?
open circulatory system
What does the open circulatory system consist of?
hemolymph (blood, interstitual fluid, lymph)
- flows through internal cavity = hemocoel
- returns to heart via holes = ostia
What type of cells is the cardiac cycle regulated by?
auto-rhythmic cells: function independently without external stimulation
What causes movement of blood through the arteries?
hydrostatic pressure
- blood pressure is very high in arteries and ultimately 0 in venules
What circulatory system and mode of respiration do annelids have?
closed circulatory system!
diffusion of gasses (gas distributed through the animal upon diffusion through skin)
(note: annelids are ringed/segmented worms)
From stem cells to immature blood cells, how do RBC develop?
- lose nucleus
- decrease size
- increase Hb content
What is hemostasis?
blood clotting
platelets = cell fragments
release - fibrinogen, fibrin
How does lymph circulate throughout the body?
- smooth muscle contractions
- valves prevent backflow
What is the role of lymph nodes?
- to filter for infectious materials - pathogens
- hold lymphocytes (WBC) which produced in bone marrow
In the urinary system, where is there high pressure and low pressure in terms of blood vasculature?
high: efferent arterioles are narrow therefore making glomerulus high pressure too
low: peritubular capillaries - therefore absorbs the small molecules (high to low gradient)
Where does filtration occur?
bowman’s capsule - glomerular filtrate
- from blood in glomerular capillaries to bowmans capsule makes filtrate
Where does reabsorption occur?
starting in the PCT and Loop of Henle
Where can all glucose, a.a., vitamins, hormones, and water all be reabsorbed?
proximal convoluted tubule
Which part of the loop of henle is permeable to water and impermeable to salt?
- descending limb
Which part of the loop of henle is impermeable to water and permeable to salt?
- ascending limb
What is the counter current exchange?
vasa recta
loop that flows in the opposite direction that absorbs water and salt in the other way
What hormones influence osmoregulation?
ADH
aldosterone
What is the role of ADH?
- ADH stimulates reabsorption of water