Lecture 15: Transport in Animals

Question 1

open vs closed circulatory system?

Answer 1

open:
fluid: hemolymph: blood and interstitial mixture
circulation: hemolymph bathes organs directly
efficiency: less efficient for delivering nutrients and oxygen
closed:
fluid: blood contained in vessels
circulation: blood flows through the vessels and doesnt directly contact organs
efficiency: more efficient for delivering nutrients and oxygen

Question 2

who dont have circulatory systems?

Answer 2

cnidarians and platyhelminthes: instead they use gastrovascular cavity to distribute gases and nutrients to the body via diffusion

Question 3

what is the function of the circulatory system?

Answer 3

to deliver nutrients and gasses to the cells and take away waste

Question 4

what are the two types of circulatory systems and what are the 3 things that each circulatory system has?

Answer 4

1. circulatory fluid: blood hemolymph
2. interconnecting tubes: vessels
3. muscular pump: heart

Question 5

what is interstitial fluid?

Answer 5

fluid that fills the spaces between most of the cells in animal bodies. in closed circulatory systems, interstitial fluid carries the gasses and nutrients between cells and the blood inside the capillaries.
but in open circulatory systems, hemolymph mixes with the interstitial fluid

Question 6

open circulatory system is found in?

Answer 6

arthropoda and mollusca and circulatory fluids don’t stay in vessels, comes in contact with cells and organs

Question 7

what are the sinuses?

Answer 7

open spaces that allow the hemolymph to reach all the tissues and organs

Question 8

blood?

Answer 8

blood is the circulatory fluid in vessels of the closed circulatory system seperate from the interstitial fluid.
consists of 3 cells in plasma
1. red blood cells: transports o2 and co2
2. white blood cells: defense and immunity
3. platelets: clotting

Question 9

closed circulatory systems are found in?

Answer 9

annelida, mollusca, and chordata

Question 10

open circulatory systems have a lower?

Answer 10

hydrostatic pressure leading to:
- slower transport of materials
- less energy required to build and maintain
ORGANISMS BETTER SUITED ARE:
- typically slow moving or sessile
- low energy requirements

Question 11

closed circulatory systems have a higher?

Answer 11

hydrostatic pressure leading to:
- faster transport of materials
- more energy required to build and maintain
- fast moving
- high energy requirements

Question 12

arteries?

Answer 12

move blood away from the heart and are thick walled to sustain high pressure

Question 13

arterioles?

Answer 13

small branches of arteries that penetrate organs

Question 14

capillaries?

Answer 14

very thin walled, form branched networks for exchange with all tissues

Question 15

venules?

Answer 15

carry blood away from capillaries and merge to form veins

Question 16

veins?

Answer 16

move blood towards the heart
- thin walled but hold large volume of blood
- contain valves to keep blood flowing in one direction

Question 17

o2 and co2 diffuse between blood and interstitial fluid through? what about salt or sugar

Answer 17

capillary walls. and pores in the capillary wall

Question 18

single vs double circulation?