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.
define antigens
any substance capable of causing the formation of antibodies when introduced into the tissue
what do helper T cells do
they will release cytokines that:
attract lymphocytes to the infection site which become semsitised and activated, thus intensifying the response
attract macrophages to the place of infection so that the macrophages can destroy the antigens by phagocytosis
intensify the phagocytic activity of macrophages
promote the action of killer T-cells
what do killer T cells do
migrate to the site of infection and deal with the invading antige. they attach to the invading cells and secrete a chemical that will destroy the antigen, and then go in search of more antigens
what do suppressor T cells do
act when the immune activity becomes excessive or the infection has been dealt with successfully. they release substances that inhibit T and B cells activity, slowing down the immune response
what is gene therapy
gene therapy refers to the treatment of disease by replacing, manipulating or supplementing non-functional genes in the cells and tissue
what is a vector
a bacterial plasmid, viral phage or other such agents used to transfer genetic material from one cell to another
how can mutagens produce mutations
Substances that are known to increase the (rate of) changes to DNA
how can DNA replication produce mutations
Errors during the process that alter DNA code
how can cell division produce mutations
Errors during the process that alter the genes or chromosomes in daughter cells formed
what is inflammation
localised non-specifc response to infection and will increase speed of healing/reduce the spread of pathogen
what wouldn’t a person not be able to feel certain things
not reaching a sufficient intensity
not enough to pass the electrochemical threshold
all or nothing response will not be fired
what does an increase up of glucose to the cells due to insulin production do
increases cellular respiration
how is the adrenal medulla stimulated t release adrenaline and noradrenaline
CNS/hypothalamus sends
electrical impulses
travels along the
ANS/sympathetic pathways
what is it called when you live in trees
arboreal
what is it called when you live on the grounds
terristal
what is dorsal root
Contains axons of sensory neurons that have their cell bodies in a small swelling known as the dorsal root ganglion.
what is ventricle root
Contain the axons of motor neurons that have their cell bodies in the grey matter of the spinal cord.
what is thallassemia
people with thalassemia have less haemogoblin in their red blood cells and therefore cannot carry as much oxygen in their blood
where is the cerebrospinal fluid located
within the arachnoid layer
