Section 5 - Blood and Organs P1

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

• plasma’s 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 do red blood cells do?

Answer 3

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 4

What are the three types of blood vessels?

Answer 4

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

Question 5

What are the functions of arteries?

Answer 5

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 6

What are the functions of the capillaries?

Answer 6

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 7

What are the functions of veins?

Answer 7

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 8

Label the parts of the right side of the heart?

Answer 8

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 9

Label the parts of the left side of the heart?

Answer 9

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 10

What does exercise do to your heart rate?

Answer 10

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 11

How does your heart rate increase?

Answer 11

• 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 12

How does hormones help control heart rate?

Answer 12

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 13

What is the path of the circulatory system?

Answer 13

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 14

What does your immune system deal with?

Answer 14

Your Immune System deals with pathogen

Question 15

What is a pathogen?

Answer 15

Pathogens are microorganisms that cause disease

Question 16

How does your immune system deal with pathogens?

Answer 16

• 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 17

What do phagocytes do?

Answer 17

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 18

What do lymphocytes do?

Answer 18

Lymphocytes produce antibodies

-every pathogen has unique molecules(antigens) on its surface

Question 19

Where is carbon dioxide transported to and from?

Answer 19

From the Muscles to the lungs

Question 20

Where is soluble products of digestion transported to and from?

Answer 20

From the small intestine to the rest of the body

Question 21

Where is urea transported to and from?

Answer 21

From liver to the kidneys

Question 22

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

Answer 22

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

Question 23

Describe the structure of an artery:

Answer 23

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

Question 24

Describe the structure of an vein:

Answer 24

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

Question 25

Describe the structure of an capillarie:

Answer 25

-lumen the layer around the lumen is one cell thick

Question 26

What is coronary heart disease?

Answer 26

When the coronary arteries that supply the blood to the muscles of the heart get blocked by layers of fatty material building up.

Question 27

What can be caused by the coronary arteries getting blocked by layers of fatty acids?

Answer 27

-the arteries become narrow, so the blood flow is restricted, so there’s a lack of oxygen to the heart
THIS CAN LEAD TO A HEART ATTACK

Question 28

What are the risk factors for coronary heart disease?

Answer 28

• diet high in saturated fats
• smoking (increasing blood pressure)
• being inactive (high blood pressure-damage arteries)

Question 29

What are risk factors?

Answer 29

Things that are linked to an increase in the likelihood that a person will develop a certain disease during their lifetime.

Question 30

How is smoking a risk factor for coronary heart disease?

Answer 30

Smoking increases blood pressure
-causing damage to the inside of coronary arteries
Chemicals in cigarettes can cause damage
-make fatty deposits more likely to form

Question 31

What does a lymphocyte do as part of the immune system?

Answer 31

• 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

Question 32

What do lymphocytes do to make it easier to fight of disease a second time?

Answer 32

-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 33

What are the three main roles of the kidneys as a part of the urinary system?

Answer 33

• removal of urea from the blood (urea is produced in the liver from excess amino acids)
• adjustment of ion (salt) levels in the blood
• adjustment of water content of the blood