Topic 8 - Exchange and transport in animals Flashcards Preview

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Flashcards in Topic 8 - Exchange and transport in animals Deck (32)
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1
Q

What are the names of substances that need to transported into and out of the body

A

water, urea, oxygen

2
Q

how does urea form and leave the body

A

waste product of proteins, diffuses from cells to blood plasma for removal from body by the kidneys

3
Q

How is water taken into the body

A

cells take up by osmosis. along with dissolved food molecules and mineral ions.

4
Q

How do oxygen and carbon dioxide enter and leave the body

A

through diffusion

5
Q

How easy an organism can exchange substances with its environment depends on its:

A

surface area to volume ratio

larger the animal- the smaller the S.A to volume ratio

6
Q

How do single celled organisms exchanged substances with their environment

A

because they have a large surface area to volume ration, it allows substances to diffuse directly into and out of them across their membrane which is much quicker

7
Q

How do multicellular organisms exchanged substances with their environment

A

more difficult to exchange substances over entire body so they have transport systems to move substances from exchange surface to rest of body due to smaller surface area to volume ratio.

8
Q

What does the rate of diffusion depend on

A

Distance/thickness of membrane
concentration difference- faster if big difference
surface area- larger =faster more surface to diffuse across

9
Q

Describe how gas exchange in mammals occurs

A

lots of alveoli in the lungs

  • blood arrives at alveoli for gas exchange which contains lots of CO2 and no much O2.
  • O2 diffuses out of air and into alveoli where O2 concentration is high and into blood where O2 concentration is low.
  • CO2 diffuses in opposite direction so is breathed out
10
Q

How are alveoli adapted for gas exchange

A
  • moist lining for dissolving gases
  • good blood supply to maintain the concentration gradients of O2 and CO2
  • very thin walls
  • very large surface area
11
Q

whats ficks law

A

rate of diffusion = surface area x concentration difference

12
Q

What is the function of red blood cells

and how are they adapted for this

A

to carry oxygen around the body

  • bioconcave disc for large surface area to absorb oxygen
  • no nucleus
  • haemoglobin (contains iron) which binds to oxygen to become oxyhaemoglobin which is then reversed to release oxygen to cells
13
Q

What is the function white blood cells

name the 2 types

A

to defend against infection

  • phagocytes are white blood cells which can change shape to engulf unwelcome microorganisms through phagocytosis
  • Lymphocytes -produce antibodies against microoragnisms. Some may produce antitoxins to neutralise any toxins produced by microoragnisms
14
Q

Why you have an infection, how will the number of white blood cells change in a blood cell count

A

they will multiply to fight off infection

15
Q

What do Platelets do and what are they

A
  • help blood clot
  • small fragments of cells clot round wound to stop blood getting out and microorganisms getting in
  • without them we would have excessive bleeding and bruising
16
Q

What is plasma

A
Plasma is the liquid that carries everything in the blood 
such as:
red, white blood cells and platelets
carbon dioxide 
urea from liver to kidney
hormones 
proteins
antibodies and antitoxins
17
Q

What are the 3 blood vessels

A

arteries, capillaries, veins

18
Q

How are arteries adapted for their function

A
  • carry blood under high pressure away from the heart so have strong, elastic walls
  • walls are thick compared to lumen.
19
Q

How are Capillaries adapted for their function

A
  • branch off arteries
  • narrow to squeeze between gaps between cells
  • one cell thick cell walls so substances can diffuse
  • supply food and oxygen + take away CO2
  • exchange substances with cells
  • large lumen
20
Q

How are Veins adapted for their functions

A

Capillaries join up to form veins,

  • lower pressure than arteries so walls arent as thick but still elastic
  • bigger lumen for increase flow
  • valves to keep blood flow in one direction
21
Q

What kind of circulatory do mammals have

A

Double circulatory, means heart pumps blood in two circuits
-deoxygenated blood goes to lungs to get oxygen
oxiginated blood goes to heart.
-second circuit takes ooxygenated blood from heart to the body for cells then returns to heart

22
Q

name an animal with a single circulatory system and how it works

A

Fish- deoxygenated blood from fish body goes to heart which pumps around again via gills which pick up
oxygen.
-heart only has 2 chambers

23
Q

How is deoxygenated blood carried around heart

A
  • through the vena cava
  • to right atrium
  • through tricuspid valve, through right ventricle
  • through semi lunar valve
  • to lungs through pulmonary artery
24
Q

How is oxygenated blood carried around heart

A
  • through the pulmonary vein to left atrium
  • through bicuspid valve,
  • to left ventricle
  • through semi-lunar valve
  • through aorta to the body
25
Q

Why is the left ventricle of the heart thicker than the right

A

because it needs more muscle because it has to pump blood to whole body under a lot of pressure

26
Q

How do you calculate cardiac output

A

heart rate x stroke volume

27
Q

What is the energy released by cellular respiration used for

A
  • metabollic processes- like breakdown of proteins from amino acid
  • contracting muscles-
  • maintaining a steady body temperature
28
Q

What is the formula for aerobic respiration

A

glucose + oxygen&raquo_space;»> carbon dioxide + water

reverse of Photosynthesis

29
Q

What is the formula for Anaerobic respiration in animals

A

glucose to lactic acid

30
Q

How does anaerobic occur

A

when there isnt oxygen available so glucose is only partly broken down to make lactic acid which can build up in muscles and lead to cramp

31
Q

What is the formula for anaerobic respiration in plants

A

glucose&raquo_space;»» ethanol + carbon dioxide

32
Q

Describe how to measure respiration

A

1) take soda lime granules are added to two test tubes.
2) cotton wool is placed in test tube and then woodlice are placed on top in one tube and in another glass beads are placed on top
3) respirometer is set up
4) syringe used to set mamometer to set level
5) left for set period at 15 degrees
6) decrease in volume deduces pressure
7) calculate the volume of oxygen taken in by woodlice per min
8) repeat at different temps