3.2)Transport in animals Flashcards
what are the 3 factors that affect the need for a transport system?
- size
2.SA/V ratio - metabolic activity
how does size affect the need for a transport system?
-small animals=cells close to the environment
-large animals=longer diffusion distance=diffusion rate is slow
how does SA/V affect the need for a transport system?
-small animal=large SA/V ratio
-large animal= small SA/V ratio
how does the level of metabolic activity affect the need for a transport system?
-active=need a good supply of oxygen and nutrients for movement=need energy
-warmth
what are the features to a good transport system?
1.fluid
2.pump
3.exchange surfaces
why is fluid necessary for a good transport system?
carries nutrients, oxygen and waste around the body–blood
why is a pump necessary for a good T.S?
create pressure to push the fluid arounf the body
why are exchange surfaces necessary for a good T.S?
allow substances to enter and leave
what is a double circulatory system?
consists of 2 separate circuits
what is pulmonary circulation?
carry blood to the lungs to pick up oxygen
what is systemic circulation?
carry oxygen to the body
what are some disadvantages of a single circulatory system?
-low blood pressure
-slow flow
-limited rate of nutrients and oxygen delivered
what are some advantages of a double circulatory system?
-not too high pressure=could damage vessels
-high pressure=flow quickly
-systemic circulation has a higher pressure than pulmonary circulation
what is an open circulatory system?
-the blood circulates through blood cavities
-tissues and cells are bathed in the blood
how does an open circulatory system work in insects?
-pumping organ=long muscular tube
-blood from the body enters the heart through pores=ostia
-heart pumps blood to the head=peristalsis
-blood pours into the body cavity
what are some disadvantages of an open circulatory system?
-low blood pressure
-slow flow
-lack of body movement can affect blood circulation
what ia closed circulatory system?
-blood stays entirely in vessels
-cells and organs bathe in tissue fluid
what are some advantages of an closed circulatory system?
-high pressure=quick flow
-faster delivery of oxygen and nutrients
-faster removal of CO2 and O2
which direction does an artery transport blood?
carry blood away from heart
what are some features of an artery?
-thick artery wall=high pressure could cause damage
-small lumen=maintain pressure
-folded inner wall=lumen can expand as blood flow increases
-wall has 3 layers
what are the 3 layers of the artery wall?
1.inner layer=tunica intima
2.middle layer=tunica media
3.outer layer=tunica adventitia
what are the component of the tunica intima?
-thin layer of elastic tissue=stretch and recoil=maintain pressure
what are the component of the tunica media?
-thick layer of smooth muscle
what are the components of the tunica adventitia?
-thick layer of collagen=strength
-layer of elastic tissue=stretch and recoil=maintain pressure
what are arterioles?
small blood vessels that distribute blood from the artery to capillaries
what are some features of arterioles?
-layer of smooth muscle=reduce friction
-ability to constrict=reduce diameter of arteriole=higher resistance=slower R.O.F
-construction=allows blood to be directed too areas which demand more O2
what are capillaries?
thin blood vessels that help with the exchange of materials between the blood and tissue fluid
what are some features of capillaries?
-thin walls
-narrow lumen
-single layer of flattened endothelial cells
-leaky walls
how are thin walls useful to capillaries?
-shorter diffusion pathway=faster exchange of substances
how is a narrow lumen useful for a capillary?
RBC are squeezed against the wall=shorter diffusion pathway + increased resistance=slower R.O.F
how is a single layer of flattened endothelial cells useful for capillaries?
shorter diffusion pathway
how are leaky walls useful capillaries?
blood plasma and dissolved substances can leave the capillary
what are venules?
vessels that transport blood from the capillaries to the veins
what are the components of the walls of venules?
layer of collagen,muscle and elastic tissue
where do veins carry blood to?
towards the heart
what are some features of veins?
-thinner walls than artery=low pressure
-large lumen=ease flow
-thin layers of collagen and smooth muscle and elastic tissue (do not need to stretch or recoil
-not actively constricted
-valves=prevent blood flow in opposite direction
-can be flattened=changes the pressure of the blood
what is blood plasma?
plasma=dissolved substances
what are erythrocytes?
RBC
what are leucocytes?
WBC
what is tissue fluid?
-plasma leaking from capillaries
-surrounds cells and tissues=supplies O2 and nutrients