February-CGP 35,37,38,39

Question 1

What are the bloods four main components?

Answer 1

Plasma
Platelets
Red blood cells
White blood cells

Question 2

Features of blood plasma?

Answer 2

• plasmas a pale yellow colour
• plasma transports
  
  • red and white blood cells and platelets
  • digested food products
  • carbon dioxide
  • urea
  • hormones
  • heat energy

Question 3

What are platelets?

Answer 3

They are small fragments of cells that help blood clot

• when you damage a blood vessel, platelets clump together to plug the damaged area
• blood clots stop you from losing to much blood and prevent microorganisms from entering the wound
• platelets are held together by a mesh of protein called fibrin

Question 4

What do red blood cells do?

Answer 4

Red blood cells carry oxygen from the lungs to all the cells in the body

• red blood cells are small and have a biconcave shape to give it a larger surface area
• contain haemoglobin which is red and contains a lot of haemoglobin, in the lungs oxygen reacts with haemoglobin to become oxyhaemoglobin
• no nucleus, more space for haemoglobin so they can carry more oxygen

Question 5

What are the three types of blood vessels?

Answer 5

Arteries-carry blood away from the heart
Capillaries-involved in the exchange of materials in tissues
Veins-carry blood to the heart

Question 6

What are the functions of arteries?

Answer 6

Carry blood under pressure

1) heart pumps blood at high pressure so artery walls are strong and elastic
2) thick walls compared to the size of the lumen(hole in the middle), have thick layers of muscle to make it strong
3) largest artery in the body is the aorta

Question 7

What are the functions of the capillaries?

Answer 7

Really small

1) arteries branch into capillaries
2) capillaries to small to see
3) carry blood really close to every cell to exchange substances
4) permeable walls so substances can diffuse in and out
5) supply food and oxygen and take waste carbon dioxide
6) small lumen, walls one cell thick so diffusion rate is increased

Question 8

What are the functions of veins?

Answer 8

Take blood back to the heart

1) capillaries join to form veins
2) bloods at lower pressure so vein walls aren’t as thick as artery walls
3) bigger lumen than arteries to help blood flow despite the lower pressure
4) have valves to keep blood flowing in the right direction
5) largest vein in the body’s the vena cava

Question 9

Label the parts of the right side of the heart?

Answer 9

Pulmonary artery(blood leaving)
Vena cava vein(blood entering)
Right atrium(chamber at the top)-receives deoxygenated blood from the body
Valves(between the two chambers)-prevent back flow of blood
Right ventricle(chamber at the bottom)-deoxygenated blood pumped to the lungs(low blood pressure)
Muscular heart wall

Question 10

Label the parts of the left side of the heart?

Answer 10

Aorta artery(blood leaving)
Pulmonary vein(blood entering)
Left atrium(chamber at the top)-receives oxygenated blood from the lungs
Valves(between the two chambers)-prevent back flow of blood
Left ventricle(chamber at the bottom)-pumps the oxygenated blood round the body(blood higher pressure)
Muscular heart wall(left ventricle has thicker wall than the right)

Question 11

What does exercise do to your heart rate?

Answer 11

Exercise increases heart rate

• When you exercise your muscles need more energy so you can respire more
• need more oxygen to cells and remove more carbon dioxide for this to happen your blood needs to flow faster so your heart rate increases

Question 12

How does your heart rate increase?

Answer 12

• exercise increases the amount of carbon dioxide in blood
• high levels of carbon dioxide are detected by receptors in the aorta and carotid artery
• receptors send signals to the brain
• brain sends signals to heart causing it to contract more frequently and with more force

Question 13

How does hormones help control heart rate?

Answer 13

The hormonal system helps to control heart rate

• when an organism is threatened the adrenal glands release adrenaline
• adrenaline binds to specific receptors in the heart, then the cardiac muscle contacts with more frequency and force, so heart rate increases and the heart pumps more blood
• this increases oxygen supply to the tissue getting the body ready for action

Question 14

What is the path of the circulatory system?

Answer 14

Heart-pulmonary artery-pulmonary vein-heart
-hepatic artery-hepatic vein-(liver)
Heart-aorta-hepatic portal artery-hepatic vein(gut to liver)-vena cava
-renal artery-renal vein-(kidneys)

Question 15

What does your immune system deal with?

Answer 15

Your Immune System deals with pathogen

Question 16

What is a pathogen?

Answer 16

Pathogens are microorganisms that cause disease

Question 17

How does your immune system deal with pathogens?

Answer 17

• once pathogens have entered your body they’ll reproduce rapidly unless they’re destroyed. That’s the job of your immune system, and white blood cells are the most important part of it
• there are two types of white blood cells phagocytes and lymphocytes

Question 18

What do phagocytes do?

Answer 18

Phagocytes ingest pathogens

• phagocytes detect things that are ‘foreign’ to the body(pathogens). They then engulf the pathogen and digest them
• phagocytes are non-specific they attack anything that’s not meant to be there

Question 19

What do lymphocytes do?

Answer 19

Lymphocytes produce antibodies

• every pathogen has unique molecules(antigens) on its surface
• when a lymphocytes comes across a foreign antigen they start to produce proteins(antibodies) these lock on to the invading pathogens and mark them out for destruction by other white blood cells. The antibodies produced are specific to that type of antigen, and won’t lock on to any others
• antibodies are then produced rapidly and flow round the body to mark out other pathogens
• some lymphocytes stay in the blood as memory cells, after the original infection has been fought off so that they can reproduce very quickly if the same antigen enters the body a second time. That’s why you’re immune to most diseases you’ve already had

Question 20

How do vaccinations work?

Answer 20

1) when you’re infected with a new pathogen your lymphocytes can take a while to produce the right antibodies, in that time you get ill, or die
2) to avoid this you can be vaccinated
3) vaccination involves injecting dead or inactive pathogen into the body. These carry antigens, so even though ,they’re harmless they still trigger an immune response - your lymphocytes produce antibodies to attack them.
4) some lymphocytes remain in the blood as memory cells so if live pathogens of the same type ever appear the antibodies to kill them will be produced fast and in great numbers.

Question 21

What does a vaccination result in?

Answer 21

It results in the manufacture of memory cells, which enables future antibody production to the pathogen to occur sooner, faster and in greater quality.

Question 22

Where is carbon dioxide transported to and from?

Answer 22

From the Muscles to the lungs

Question 23

Where is soluble products of digestion transported to and from?

Answer 23

From the small intestine to the rest of the body

Question 24

Where is urea transported to and from?

Answer 24

From liver to the kidneys

Question 25

What is involved with blood clotting and what does it do?

Answer 25

Platelets, and prevents blood lose and entry of micro-organisms

Question 26

Describe the structure of an artery:

Answer 26

• thin lumen(the lumens the inside)surrounded by a lining layer
• thicker elastic layer
• thicker muscle layer
• tough outer layer

Question 27

Describe the structure of an vein:

Answer 27

• larger lumen(the lumens the inside)surrounded by a lining layer
• thinner elastic layer
• thinner muscle layer
• tough outer layer

Question 28

Describe the structure of an capillarie:

Answer 28

-lumen the layer around the lumen is one cell thick