B7 Flashcards
how do electrical impulses travel around the body
along neurones
what is the mammalian nervous system comprised of
CNS, PNS
what does CNS contain
brain, spinal cord
what does PNS contain
nerves outside brain and spinal cord
what is the role of the nervous system
coordination and regulation of body functions
what are the types of neurones
motor, sensory, relay
what type of neurone is this
motor
what type of neurone
sensory
what type of neurone
relay
function of motor neurone
carry nerve impulses from CNS to effectors
function of sensory neurone
carry nerve impulses away from receptor cells to CNS
function of relay neruones
connect one neurone to next in CNS
what is a reflex action
means of automatically and rapidly integrating and coordinating stimuli with response of effectors
what is process of simple reflex arc
receptor, sensory neurone, relay neurone, motor neurone, effector
what are sense organs
groups of receptor cells responding to specific stimuli
(light, sound, touch, temperature, chemicals)
what is a hormone
chemical substance produced by a gland and carried by the blood
alters activity of one or more specific target organs
what are the endocrine glands
- adrenal glands
- testes
- ovaries
- pancreas
what do the adrenal glands secrete
adrenaline
what does the pancreas secrete
insulin and glucagon
what do the testes secrete
testosterone
what do the ovaries secrete
oestrogen
what is adrenaline
hormone secreted in “fight or flight” situations
effects of adrenaline
- increased breathing rate
- increased heart rate
- increased pupil diameter
what is homeostasis
maintenance of constant internal environment
how does homeostatic control work
- negative feedback
- keep internal environment with reference to set point
- if values move beyond set point, various processes work to return them back to normal
what happens when blood glucose concentration is too high
- insulin released
- stimulates cells in liver and tissues to take in glucose from blood
- use for respiration or convert to glycogen for storage
what happens when blood glucose concentration is too low
- glucagon released
- stimulates liver cells to convert stored glycogen into glucose
what are components of skin
hairs, hair erector muscles, sweat glands, receptors, sensory neurones, blood vessels, fatty tissue
how does body react when it is too cold
- vasoconstriction: less blood flow to surface of skin to retain more heat
- shivering: mvmt t release heat by constant, uncontrollable muscle contractions
- hair stands on end: traps air, good insulator
how does body react when it is too hot
- vasodilation: more blood flows to surface of skin to lose more heat to radiation
- sweat produced: as evaporate, cools body
what is a drug
any substance taken into the body that modifies or affects chemical reactions in body
how are antibiotics used to treat bacterial infections
- break bacterial cell membranes
- prevent formation of new cell walls
how do antibiotics affect viruses
no effect
how can using antibiotics only when necessary limit development of resistant bacteria
prevent natural selection that comes from survival and reproduction of resistant bacteria
example of resistant bacteria
MRSA
