Part 1 of Chapter 6: Transport in humans! 🫀 Flashcards
1
Q
What is blood?
A
- Blood is a fluid tissue.
- It consists of different types of cells such as red blood cells, white blood cells, and platelets and it is suspended plasma (fluid).
2
Q
What is haemoglobin?
A
- Haemoglobin is present in the mammalian red blood cells.
- It is a red pigment that combines reversibly with oxygen, which enables the red blood cell to transport oxygen from the lungs to the rest of the body.
3
Q
What is the word equation for haemoglobin and oxygen?
A
- Haemoglobin (purplish red colour) + Oxygen (O2) –>/<– Oxyghaemoglobin (bright red colour)
4
Q
What is the physical appearance of a red blood cell?
A
- The red blood cell is a circular and flattened biconcave disc with its centre, that is thinner than the edges of the red blood cell.
- Thus, this increases the surface area-to-volume ratio, and it allows the cell to absorb and release oxygen at a faster rate.
5
Q
What is the advantage of having an absence of a nucleus in the red blood cell?
A
- The absence of a nucleus in the red blood cell increases its capacity for haemoglobin and thus more oxygen.
6
Q
What is the advantage of having flexible red blood cells?
A
- Red blood cells are flexible, and they can change into a bell-shaped structure to flow through small blood vessels easily.
7
Q
What is the mechanism by which the red blood cell transports oxygen to the cells of the body?
A
- In the lungs, oxygen level is higher, and oxygen diffuses from the alveoli into the blood as the blood passes through the lungs.
- Oxygen binds to the haemoglobin in red blood cells to form oxyhaemoglobin.
- The red blood cells transport oxyhaemoglobin to all of the tissues of the body.
- As blood passes through tissues containing very little oxygen, the oxyhaemoglobin releases oxygen.
- The oxygen then diffuses into the tissue cells, allowing every cell in the body to receive its oxygen supply.
8
Q
How does white blood cells play a role in keeping the body healthy?
A
- White blood cells play a role in keeping the body healthy by fighting diseases.
- The 2 main types of white blood cells are phagocytes and lymphocytes.
9
Q
What is the process phagocytosis?
A
- Phagocytosis Is the process where some white blood cells ingest foreign particles such as bacteria and digests them.
10
Q
What happens when pathogens enter the blood stream?
A
- When pathogens enter the bloodstream, they stimulate lymphocytes to produce antibodies that recognise the foreign particles.
- Antibodies attach to the bacteria and cause the bacterial cell membrane to rupture.
- They bind to the bacteria and cause them to clump together or agglutinate to facilitate phagocytosis.
- They also bind to the toxins produced by the bacteria and neutralise them.
11
Q
What is a blood platelet?
A
- A blood platelet is a fragment of cytoplasm that plays a part in blood clotting.
- The clotting of blood helps to seal wounds to reduce excessive blood loss and prevents the entry of foreign particles and infection by pathogens.
- platelets contain enzymes that aid the conversion of fibrinogen, a soluble plasma protein to insoluble fibrin threads.
- The fibrin threads then entangles blood cells to form a clot or scab.
12
Q
What is plasma?
A
- Plasma is a pale yellowish fluid that is composed of mainly water and a mixture of various dissolved substances.
- It serves as a transport medium that delivers nutrients and transports waste products for one part of the body to another (organ.)
13
Q
What are the substances transported by blood?
A
- Digested food
- E.g. Glucose, amino acids, mineral salts, fats, and vitamins.
Carried from: Intestine.
Carried to:
- Other parts of the body.
- Excessive mineral salts are transported to the kidneys for excretion (passed out of the body through urine/faeces). - Excretory products
- E.g. Nitrogenous waste and carbon dioxide.
Carried from: All parts of the body (for both nitrogenous waste and carbon dioxide).
Carried to:
- Kidney for nitrogenous waste.
- Lungs for carbon dioxide. - Hormones
Carried from: Glands
- E>g. Sex glands (produce sex hormones)
Carried to:
- Target organs - Oxygen, which is transported by haemoglobin in the red blood cells.
Carried from: Lungs.
Carried to:
- All parts of the body for cellular respiration, this ensures the survival of that living thing/human.
side point:
- Food substances, excretory products, and hormones are carried in solution in the plasma whereas oxygen is carried in the red blood cells.
14
Q
What is tissue transplant and organ transplant?
A
- Tissue/organ transport is the replacement of badly damaged/diseased tissue/organ with a healthy one from a donor.
15
Q
What are the 4 blood groups that exists in humans?
A
- A, B, AB and O blood groups.
- These groupings are based on the types of antigens n the red blood cells and antibodies present in the plasma.
