5 - Blood and Organs Flashcards Preview

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Flashcards in 5 - Blood and Organs Deck (45)
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1

What are the four main components in blood?

Plasma
Platelets
Red Blood Cells
White Blood Cells

2

What is plasma?

A pale yellow liquid that carries everything that needs transporting around the body
e.g.
- Red and white blood cells and platelets
- Digested food products from the gut to body cells
- CO2 from the body cells to the lungs
- Urea from the liver to kidneys
- Hormones (acting as chemical messengers)
- Heat energy

3

What are platelets?

Small fragments of cells that help blood clot
- When you damage a blood vessel platelets clump together to 'plug' the hole
- Known as blood clotting which stops too much blood being lost and microorganisms entering the wound

4

What holds protein together?

The platelets are held together by a protein called fibrin

5

What is the function of Red Blood Cells?

Transport oxygen from the lungs to all the cells in the body

6

What are some adaptations for Red Blood Cells?

- Biconcave shape to give a large surface area for absorbing and releasing oxygen
- Contain haemoglobin (which gives blood its colour) which contains lots of iron
- No nucleus so there is more space for haemoglobin and oxygen

7

What does haemoglobin do?

- Gives blood its colour
- Contains lots of iron
In the lungs - reacts with oxygen to become oxyhaemoglobin
In body tissues - reverse reaction to release oxygen to the cells

8

What does haemoglobin do?

- Gives blood its colour
- Contains lots of iron
In the lungs - reacts with oxygen to become oxyhaemoglobin
In body tissues - reverse reaction to release oxygen to the cells

9

What is the role of the immune system?

Deals with pathogens to make the body healthy

10

What is the role of phagocytes?

- Detect things that are 'foreign' to the body
- Engulf the pathogens and digest them
- Are non-specific so will attack anything that is not meant to be there

11

What is the role of lymphocytes?

- When they come across a foreign antigen they will produce proteins called antibodies
- Antibodies lock onto the invading pathogens and mark them for destruction by other white blood cells
- Specific so only attack one type of antigen
- Some are kept as memory cells (making you more immune to the disease)

12

What are pathogens?

- Microorganisms that cause disease
- Once in the body they will reproduce rapidly unless stopped and destroyed
- They have antigens on their surface

13

How do vaccinations protect from disease?

- A dead or inactive pathogen is injected into the body
- The harmless antigens are detected by the lymphocytes and the body produces antibodies to fight the antigens
- Some antibodies are kept as memory cells
- If the real disease were to attack the body there would already by antibodies to fight it off quickly

14

How do vaccinations protect from disease?

- A dead or inactive pathogen is injected into the body
- The harmless antigens are detected by the lymphocytes and the body produces antibodies to fight the antigens
- Some antibodies are kept as memory cells
- If the real disease were to attack the body there would already by antibodies to fight it off quickly

15

What are the three types of blood vessels?

- Arteries
- Capillaries
- Veins

16

What is role of arteries?

- Carries blood away from the heart
- Blood is pumped at high pressure (it has to go all around the body) so the walls are strong and elastic
- Thick walls compared to the lumen because they contain a lot of muscle
- The largest artery is the aorta
- Branch into capillaries

17

What is the role of capillaries?

- Involved in exchange of materials at the tissue
-

18

What is the role of capillaries?

- Involved in exchange of materials at the tissue
- Really tiny and carry blood very close to every cell in the body to exchange substances
- Permeable walls for things to diffuse in and out
- Supply food and oxygen and take away waste like CO2
- Walls only one cell thick which increases the rate of diffusion by decreasing the distance to travel
- Nucleus in the small wall and small lumen
- Join up to form veins

19

What is the role of veins?

- Carry blood to the heart
- The blood is at a lower pressure so the walls are thin and the lumen big (to help blood flow well)
- There are valves in the lumen to keep blood flowing in the right direction
- The largest vein is the vena cava
- Injections happen in the veins because the blood has been all around the body so shows what is in the blood (e.g. waste products)

20

What happens in the right atrium?

Deoxygenated blood from the body is received

21

What happens in the right ventricle?

Deoxygenated blood is pumped through to the lungs via the pulmonary artery

22

What happens in the left atrium?

Oxygenated blood from the lungs is received

23

What happens in the left ventricle?

Oxygenated blood is pumped to the rest of the body via the aorta
- Has a thicker wall than the right ventricle because more muscle is needed to pump it around the body

24

What is the role of the valves in the heart?

To prevent backflow

25

How does exercise increase heart rate?

- Muscles need more energy so respire more
-

26

How does exercise increase heart rate?

- Muscles need more energy so respire more
- More oxygen is needed and less carbon dioxide so the heart rate increases

27

How does the heart rate increase?

- Exercise increases the amount of CO2 in the blood
- High levels are detected by receptors in the aorta and carotid artery (in the neck)
- The receptors send signals to the brain
- The brain sends signals to the heart which contracts more frequently and with more force

28

How does the hormonal system help increase heart rate?

- When an organism is threatened the adrenal glands release adrenaline
- Adrenaline binds to specific receptors in the heart and causes the cardiac muscles to contract more frequently and with more force
- Heart rate increases and the heart pumps more blood
- This increases oxygen supply to the tissues getting the body ready for action

29

What does pulmonary mean?

To do with the lungs

30

What does hepatic mean?

To do with the liver