GCSE) PREP EXAM AND COMPLETE
ANSWERS.
Plasma - Answer Transports dissolved substances around the body
red blood cells - Answer Transports oxygen from lungs to body cells
white blood cells - Answer Protects body against infection
Ateries - Answer Carries blood away from the heart
Veins - Answer Carries blood into the heart
Capillaries - Answer Substances such as oxygen and glucose to diffuse in and out of cells
Platelets - Answer Helps the blood to clot
Correlation - Answer Doesn't prove cause simply suggests they might be linked
causal mechanism - Answer something that explains how one factor influences another through a
biological process
risk factors - Answer Factors leading to an increased rate of disease
Cancer - Answer Changes in cells that lead to uncontrolled growth and mitosis
, Benign tumour - Answer Growth of abnormal cells contained in one area in a membrane. Doesn't
invade other parts of the body
Malignant tumours - Answer Invade neighbouring tissues and move into bloodstream and spread to
form secondary tumours.
Health - Answer State of physical and mental well being
coronary arteries - Answer Provide oxygen to muscle cells of heart used in respiration for contraction
CHD (coronary heart disease) - Answer Layers of fatty material build up in coronary ateries
upper epidermis - Answer Transparent- allows light to pass through to the photosynthetic cells
lower epidermis - Answer contains stomata
palisade mesophyll - Answer Full of chloroplasts for photosynthesis
Spongy mesophyll - Answer Full of air spaces for c02 to diffuse from stomata to spongy mesophyll to
palisade cells
Xylem - Answer Transports water from roots to stem and leaves.
Structure of xylem - Answer Hollow tube strengthened by lignin for efficient transport of water in
transpiration stream
Phloem - Answer Transports dissolved sugars from leaves to rest of plant. Stored as starch or used for
respiration
Structure of phloem - Answer Tubes of elongated cells. Cell sap move from one phloem cell to another
through pores in end walls