5th Form Definitions and Key Concepts Flashcards
digestion
the breakdown of large, insoluble molecules into smaller, more soluble ones
adrenaline
a hormone produced by the adrenal glands in response to fear or stress. increases heart rate and boosts the delivery of blood to the muscles, flight or fight response
memory cell
a lymphocyte that can recognise a pathogen previously encountered, either from vaccination or infection, and can be produce specific antibodies for that pathogen
vaccination
the introduction of dead or inactive forms of a pathogen (antigens) into the body to stimulate the production of antibodies specific to that pathogen by white blood cells. it will make the response quicker
antidiuretic hormone (ADH)
a hormone produced by the pituitary gland that increases the reabsorption of water in the collecting duct of the kidney
auxins
plant hormones that control cell elongation and plant growth
central nervous system (CNS)
the bran and spinal cord which coordinates the response of effectors
coordination centres
areas of the body like the brain, spinal cord and pancreas that recieve and process information from receptors
effectors
muscles or glands which bring about responses
eye
a sense organ containing photoreceptors in the retina sensitive to light intensity (rods) and colour (cones)
geo/gravitropism
a plants directional growth in response to gravity controlled by auxin
homeostasis
maintenance of a stable internal environment in the body
insulin
a hormone secreted by the pancreas when blood glucose concentration is too high, reducing blood glucose concentrations by increasing the uptake of glucose from the blood into the liver
nerves
cells that link the CNS to sense organs, sensory neurones connecting receptors to the CNS, relay neurones connecting sensory neurones to motor neurones in the CNS and motor neurones which connect to effectors
neurotransmitters
chemicals that are released at synapses
oestrogen
a female sex hormone released by the ovaries and stimulates the growth of the uterus lining whilst inhibiting the release of FSH
phototropism
a plants directional growth in response to light
receptors
cells that detect a stimulus (photoreceptors, thermoreceptors)
reflex arc
a rapid and automatic response to a stimulus. pathway of neurones: stimulus -> receptor -> sensory neurone -> relay neurone -> motor neurone -> effector -> response