exam Flashcards
Explain the role of ADH in the maintenance of water balance in the body
water concentration of blood plasma decreases/osmotic pressure of the blood increases
osmoreceptors (in hypothalamus) detect decrease in water concentration/increase in osmotic pressure
hypothalamus stimulates posterior pituitary gland 1 to release ADH 1
permeability of the distal convoluted tubule and collecting tubule
(of the nephron) to water is increased
Increased amount of water is reabsorbed into the blood/water concentration of blood plasma increases/osmotic pressure of the 1 blood decreases
Total 6
describe the arrangement of nerve fibre in a nerve
nerve fibres are arranged into bundles held together by connective tissue, with multiple bundles joining together to form a nerve
Describe two processes controlled by insulin that ensure the maintenance of blood glucose levels. Include the locations in the body where each process occurs
Conversion of glucose to glycogen
In the liver/muscles
Conversion of glucose to lipids/fats
In adipose tissue
Increased uptake of glucose
Body cells
Increased rate of protein synthesis
Body cells
Conversion of glucose to amino acids
In the liver/muscle
Explain what is meant by a selectively advantageous mutation.
A change in DNA
Provides a survival advantage (to a particular genotype)
Under particular environmental conditions/selective pressure
Describe how the link between the sickle-cell allele and malaria can lead to changes in the allele frequencies in a population.
Malaria reduces reproduction of normal cell individuals
Sickle-cell allele selected for/favoured
Carriers of sickle cell reproduce at greater rates
Sickle cell trait allele combinations increase/allele frequency of sickle cell increases
what is the difference between the cerebral cortex, cerebellum and cerebrum
the cerebellum is the lobe at the very back of the brain that hangs off
cerebrum is the largest part of the brain
cerebral cortex is the outer layer of the cerebru
what can the cerebral cortex be broken into
frontal lobe
parietal lobe
occipital lobe
temporal lobe
what is non specific defence
immune defence that works against all pathogens, and is the body first line of defence
what are specific defences?
are directed at a particular pathogen
what is the oily substance that comes out of the skin
sebum
what is ear wax called
cerumen
what is a fever
an elevation of body temperature, above the normal level of 37
what is inflammation
the response to damage to a tissue, involves swelling, heat, pain and redness in the affected area
what is a pyrogen
a substance that results in a fever
how does lymph nodes provide non-specific defence
each node contain masses of lymph tissue, the cells of which are criss-crossed by a network of fibres. lymph entering the lymph nodes contains cell debris, foreign particles and microorganisms that have penetrated the bodys external defences.