topic 8 - exchange and transport in animals

Question 1

Why do we need to transport substances into an out of a range of organisms, including oxygen, carbon dioxide, water, dissolved food molecules, mineral irons and urea?

Answer 1

Or organisms, mistaken substances that they need from the environment and get rid of any waste products

Question 2

How is water transported along the body?

Answer 2

Water is taken up by cells by osmosis
In animals dissolved food molecules and mineral irons diffuse along with it

Question 3

What is urea and how is it transported around the body

Answer 3

Area is a waste product produced by animals from proteins
It diffuses from cells into the blood plasma for removal from the body by the kidneys

Question 4

Why do we need to exchange services and the transport system in multicellular organisms including the calculation of surface area?

Answer 4

The larger the organism is, the smaller surface area compared to its volume

Question 5

How does gas exchange happen in mammals regarding

Answer 5

• Blood arriving at the alveoli has just returned to the lungs from the rest of the body, so it contains lots of carbon dioxide and not much oxygen.
• this maximise the concentration gradient for both gases
• senses diffuse faster. If there’s a big difference in concentration between the area they are diffusing from the area they are diffusing to.
• oxygen diffuses out of the air in the alveoli into the blood where the concentration of oxygen is low
• carbon dioxide diffusers in the opposite direction to be breathed out

Question 6

How is the alveoli adapted for gas exchange by diffusion between air and the lungs and blood in capillaries?

Answer 6

• A moist lining for dissolving gas
• A good blood supply to maintain the concentration gradient of oxygen and carbon dioxide
• Very thin walls – minimising the distance that gases have to move
• And enormous surface area about 75 m² in humans

Question 7

How are red blood cells specialised to its function in the blood?

Answer 7

• they carry oxygen from the lungs to all cells in the body
• They have a biconcave dish shape to give a large surface for absorption of oxygen
• they don’t have a nucleus. This allows more room to carry oxygen.
• they carry a red pigment called haemoglobin which contains
• in the lungs. Haemoglobin binds the oxygen to become oxyhemoglobin in body tissues. The reverse happens. Oxyhemoglobin split up into haemoglobin and oxygen to release oxygen in the cells.

Question 8

How are white blood cells adapted to the function in the blood?

Answer 8

• Phagocytes are white blood cells that can change shape to engulf unwelcome microorganisms
• lymphocytes are white blood cells that produce antibodies against microorganisms. Some produce anti-toxins to neutralise any toxins produced by the microorganism.
• when you have an infection in your white blood cells multiplied to fight it off

Question 9

How is platelet adapted to their function in the blood?

Answer 9

There are small fragments of cells and they have no nucleus
They helped the blood to clot at a wound to stop all your blood pouring out to stop microorganisms getting in
Lack of platelets can cause excessive bleeding and bruising

Question 10

How is plasma adapted to its function in the blood?

Answer 10

Plasma is the liquid that carries everything in the blood
It carries:
- Red and white blood cells and
- Nutrients like glucose and am
- Carbon dioxide from the or
- Urea from the liver
- hormones
- proteins
- Antibodies and antitoxins produced by the white blood cell cells

Question 11

What are the three types of blood vessels?

Answer 11

Arteries, which carry blood away from the heart
Capillaries which are involved in the exchange of materials at the tissue
veins which carried blood to the heart

Question 12

How are the arteries adapted to a function?

Answer 12

The hot pumps blood out at a high pressure so the artery walls are strong and elastic
The walls are thick compared to the size of the hole down the middle the lumen
They contain thick layers of muscle to make them strong and elastic fibres to allow them to stretch and sling back

Question 13

How are the capillaries adapted in the blood?

Answer 13

Arteries branch into the capillaries
Capillaries are really tiny
They are very narrow, so they can squeeze into the gaps between cells. This means they can carry the blood really close to every cell in the body to exchange substances with them.
They have permeable walls so substance can diffuse in and out
They supply food and oxygen and take away waste like carbon dioxide
The walls are usually one Celtic this increases the rate of diffusion by decreasing the distance of which it occurs

Question 14

How are veins adapted to their role?

Answer 14

Capillaries eventually joined up to form veins
The blood is at a lower pressure in the vein, so the walls don’t need to be a stick as a artery walls
They have a bigger lumen then arteries to help blood flow despite the lower pressure
They also have valves to help keep the blood flowing in the right direction

Question 15

In the first and second circuit that the heart pumps blood around the body what is pumped?

Answer 15

In the first circuit, the heart pumps deoxygenated blood to the lungs taken in oxygen it then returns to the heart
in the second circuit the heart pumps oxygenated blood around all the other organs of the body to deliver oxygen to the body cells deoxygenated blood then returns to the heart

Question 16

What happens with animals like fish who have a single circulatory system?

Answer 16

Deoxygenated blood from the fish’s body travels to the heart, which then pumps it right round the body again in a single circuit

Question 17

How does the heart work

Answer 17

The right atrium of the heart receives deoxygenated blood from the body
The deoxygenated blood moves through the right ventricle which pumps it to the lungs
The left atrium receives oxygenated blood from the lungs
The oxygenated blood then moves through to the left ventricle which pumps it out round the whole body

Question 18

What is cellular respiration?

Answer 18

An exothermic reaction which occurs continuously in living cells to release energy for metabolic processes, including aerobic and anaerobic respiration

Question 19

What is aerobic respiration?

Answer 19

Aerobic respiration is what happens when there’s plenty of oxygen available
It’s the most efficient way to transfer energy from glucose

Question 20

What is anaerobic respiration?

Answer 20

When you do really vigourous exercise, your body can’t supply enough oxygen to your muscles for aerobic respiration even though your heart rate and breathing rate increase as much as they can. Your muscles have to start respiring anaerobically as well.
it transfers muscle energy than aerobic respiration so it’s much less efficient. The glucose is only partially broken down. A lactic acid is also produce.
The lactic acid buildup in the muscles it gets painful and leads to a cramp

Question 21

What is the difference between anaerobic respiration in plant and animals?

Answer 21

Plants can buy without oxygen too, but they produce ethanol and carbon dioxide instead of lactic acid

Question 22

How to calculate cardiac output

Answer 22

Stroke Volume X heart rate

Question 23

How to investigate rate of respiration

Answer 23

• soda lime granules are added to 2 test tubes. Soda lime absorbs the carbon dioxide produced by the respiring woodlice in the experiment
• A bowl of cotton wool is placed above the soda lime in each tub. Woodlice are placed on top of the cotton wool. Glass speed with the same mass as the woodlice are used in the control tube
• The respirometer is then set up. The syringe is used to set the fluid in the manometer to a known level. The apparatus is then left for a set period of time in a water bath set to 15°.
• During this time that we decrease in the volume of air in the test tube containing the wood lice. This is because the would life use of oxygen in the tube as they respire.
• The decrease in volume reduces the pressure in the tube, causing the coloured liquid in the monometer to move towards a test tube containing the woodlice
• The distant moved by the liquid in a given time is measured. This value can then be used to calculate the volume of oxygen taking in by the woodlice permanent. This gives you rate of respiration.
• Repeat steps with the water bath set a different temperatures