Topic 2a - Tissues, organs and organ systems ( 5. circulatory system - the blood)

Question 1

what is blood

Answer 1

blood is a tissue, group of similar cells which work together to perform a specific function. the function is to transport substances around the body. red blood cell, white blood cells and platelets. which are all suspended in a liquid called plasma

Question 2

function of a red blood cell

Answer 2

to transport oxygen around the body

Question 3

adaptations of blood cells

Answer 3

biconcave shape to give large surface area for absorbing oxygen
contain red pigment called haemoglobin which carries oxygen
no nucleus so it has more space for haemoglobin meaning more oxygen

Question 4

describe the process of transporting oxygen

Answer 4

in the lungs oxygen diffuses into the blood. oxygen combines with haemoglobin in rbcs to become oxyhaeomoglobin . in body tissues reverse happens oxyhaemoglobin splits up into haemoglobin and oxygen to release oxygen in the cells.

Question 5

function of a white blood cell

Answer 5

defend against microorganisms that cause disease

Question 6

what are the different ways abcs defend against microorganisms

Answer 6

engulf unwelcome microorganisms and digest them
produce antibodies to fight microorganisms
can produce antitoxins to neutralise any toxins produced by the microorganisms
wbcs do have a nucleus

Question 7

function of platelets

Answer 7

small fragments of cells, help the blood to clot at a wound. seals to wound to stop you from losing so much blood. also stops microorganisms from getting in the wound. lack of platelets cause excessive bleeding and bruising.

Question 8

what is plasma

Answer 8

plasma is a pale straw coloured liquid which carries just about everything in the blood

Question 9

what does plasma carry

Answer 9

rbc, abc, platelets
nutrients like glucose and amino acids
co2 from the organs to the lungs
urea from the liver to the kidney
hormones 
proteins
antibodies and antitoxins