unit3 Flashcards
what does the PNS contain
The PNS consists of the somatic nervous system (SNS) and the autonomic nervous system (ANS)
what do sensory and motor neurons do
Sensory neurons take impulses from sense organs to the CNS. Motor neurons take impulses from the CNS to muscles and glands.
what is the cerebral cortex
The cerebral cortex is the centre of conscious thought. It also recalls memories and alters behaviour in the light of experience.
what is teh deal with sight and switching
The left cerebral hemisphere deals with information from the right visual field and controls the right side of the body and vice versa.
what does the sensory memory do
Sensory memory retains all the visual and auditory input received for a few seconds.
how does teh stem memory work and what is teh wroking memory model
STM can also process data, to a limited extent, as well as store it. This ‘workingmemory model’ explains why the STM can perform simple cognitive tasks.
where are neurotransmitters stored and. what do they do
Neurotransmitters are stored in vesicles in the axon endings of the presynaptic neuron. They are released into the cleft on arrival of an impulse. They diffuse across the cleft and bind to receptors on the membrane of the postsynaptic neuron.
what do u need for an impulse to travel
A minimum number of neurotransmitter molecules must attach to receptors in order to reach the threshold on the postsynaptic membrane to transmit the impulse.
what are antagonists
Antagonists are chemicals that bind to specific receptors blocking the action of a neurotransmitter at a synapse.
what does mast cells release
Histamine is released by mast cells causing vasodilation
what do cytokines do and what are th
Phagocytes release cytokines which attract more phagocytes to the site of infection.
Cytokines are protein molecules that act as a signal to specific white blood cells causing them to accumulate at the site of infection.
what are lymphocytes what do they do
Lymphocytes have a single type of membrane receptor which is specific for one antigen. Antigen binding leads to repeated lymphocyte division resulting in the formation of a clonal population of identical lymphocytes.
t lypmhetse processssss
T lymphocytes attach onto infected cells and release proteins. These proteins diffuse into the infected cells causing production of self- destructive enzymes which cause cell death. The remains of the cell are then removed by phagocytosis.
what happens is an individual is inffected with a disease again
During the secondary response, antibody production is greater and more rapid than during the primary response.
what are teh antigens in vaccines like
The antigens used in vaccines can be inactivated pathogen toxins, dead pathogens, parts of pathogens and weakened pathogens.
