Chapter 7 : Transport In Humans Flashcards
(36 cards)
Name the 4 components of blood
- Plasma
- White blood cells
- Platelets
- Red blood cells
What’s is transported in the plasma (5) ?
- Proteins such as fibrinogen, prothrombin and antibodies
- Mineral salts ( chlorides, sulfates of calcium and sodium )
- Food substances ( glucose, fats and amino acids )
- Waste products ( Urea, Uric acid and creatinine)
- Hormones
What is the main function of the RBC. Where is RBC produced and destroyed
Transport of O2 to different parts of the body. Created in bone marrow and destroyed in the spleen.
What are the key features of the RBC (4) ?
Presence of haemoglobin
Lack of nucleus
Biconcave shape
Elastic ( able to squeeze through tiny blood capillaries )
What are some unique characteristics of white blood cells (4) ? Where are white blood cells formed and destroyed?
- Mobile ( able to move and change their shape to squeeze through walls of blood capillaries )
- Colourless ( lack of haemoglobin )
- Irregular in shape
- Contains a nucleus
WBC are formed in the the cells of the bone marrow and destroyed in the spleen.
What are the 2 type of WBC called ?
Lymphocytes and phagocytes
Why are the differenence in function of the phagocyte and the lymphocyte
Lymphocytes produce antibodies which act by
A) destroying bacteria by rupturing their surface membrane
B) clumping bacteria together so that they can be easily engulfed by the phagocytes
C) neutralise toxins produced by the bacteria
Phagocytes ingest foreign particles and ingest them intracellularly
In the process, some phagocytes are killed and together with dead bacteria form pus
Structural difference of phagocytes and lymphocytes (5)
- Lymphocytes have a large round nucleus, while phagocytes have a lobed nucleus
- Lymphocytes have small amount of cytoplasm while phagocytes have large amount of cytoplasm
- Lymphocytes have a non granular cytoplasm while phagocytes have a granular cytoplasm
- Lymphocytes have a round shape while phagocytes have an irregular shape
- The movement of lymphocytes are limited while the phagocytes are mobile and ca hence move freely
Are blood platelets cells ?
No. They are fragments of cytoplasm which are membrane bound
What antigens and antibodies are present on each blood type
A : Antigen A and Antibody B
B : Antigen B and Antibody A
O : Both Antibodies A and B, no antigens
AB : Both Antigens A and B, no antibodies
Why can blood group AB receive blood group O blood
Antibodies A and B in the blood group O blood are in the plasma, and would not be transferred to the blood group AB person
What happens when antibodies bind with the antigens present on the donor’s blood
Agglutination or clumping of blood would occur.
Describe the process where oxygen is transferred from air sac to the RBC (3)
Blood passes through the lungs and oxygen diffuses from the air sac into the blood.
The oxygen passes through a thin film of moisture which dissolves the oxygen before it enters the bloodstream
Oxygen binds with haemoglobin to produce oxyhemoglobin.
How does blood clot when there’s an open wound ?
- Damaged tissue and platelets release thrombokinase ( enzyme )
- Thrombokinase converts prothrombin into thrombin
- Thrombin converts soluble fibrinogen into insoluble fibrin threads, entangling blood cells to form a clot
Name the 3 types of blood vessels
Artery
Capillary
Vein
State the function and adaptation of the artery (1+2)
Transport oxygenated blood away from the heart to other organs in the body
Have thick muscular walls to support high pressure blood which is coming from the heart
Small lumen to maintain high pressure of blood throughout the body
State the function and adaptations of the veins (1+3)
Transport deoxygenated blood back to the heart
Thin walls with less elastic tissue as BP in the veins is lower
Presence of semilunar valves to prevent the back flow of blood
Wider lumen due to lower pressure in the veins
Adaptations of the capillaries
Capillary network : Larger SA and total cross sectional area ( more efficient exchange of substances between blood and cells
High cross sectional area : Lower BP and slower blood flow, more time for exchange of substances
One cell thick : shorter distance for diffusion, increases speed of exchange of substances
What is tissue fluid and what is the function of tissue fluid?
Colourless fluid found in between cells
Nutrients and oxygen diffuse into the tissue fluid before diffusing into the cells. SImilarly, CO2 diffuses into the cells before diffusing into the capillaries
Why is double circulation better than single circulation
Blood enters pulmonary circulation at lower pressure, ensuring sufficient time for blood to be fully oxygenated before returning to the heart
Blood is pumped into systemic circulation at high pressure —> quick distribution to all tissues in the body
Difference between pulmonary and systemic circulation
Pulmonary circulation is between heart and lungs
Systemic circulation is from the heart to the rest of the body
What is the difference of pulmonary arteries and normal arteries
Arteries transport oxygenated blood away from the heart while the pulmonary artery transports deoxygenated blood away from the heart
The heart is surrounded by __________ . It consists of 4 chambers and is located in the ________ ________
Pericardium, thoracic cavity
What is the muscular wall between the median and the septum and what is its function
The Median septum. Prevents mixing of oxygenated blood with deoxygenated blood
