topic 2-cells and control Flashcards
what is mitosis
when cells divide and it makes two identical cells
what is mitosis used for
grow or replace cells and to reproduce
what’s the cell cycle in order
interphase, prophase, metaphase, anaphase, telophase
what happens in the interphase
it duplicates its DNA
what happens in prophase
the membrane around the nucleus breaks down
what happens in metaphase
the chromosome line up in the centre of the cell
what happens in anaphase
spindle fibres pull the chromosomes to different ends
what happens at telophase
membranes form around each chromosome
what is produced at the end of mitosis
two daughter cells
what is cell differentiation
where the cell changes to become specialised for its job
what is cell division
by mitosis
what is cell elongation
the plant cell expands making the plant grow
how is cancer caused
where the cells divide by mitosis uncontrollably
what chart is used to monitor growth
percentile charts
what are stem cells
cells that can differentiate into different types of cells
where are stem cells found (children)
human embryos
where are stem cells found (adults)
bone marrow
what are meristems
the only cells in a plant that divide by mitosis
give one disadvantage of using stem cells in medicine
tumour development because the cells can divide rlly quick
what makes up the central nervous system (CNS)
the brain and spinal cord
what does the spinal cord do
relays information between the brain and the rest of the body
what are the 3 main parts in the brain
cerebrum, cerebellum, medulla oblongata
what does the cerebrum control
memory, language, movement
what does the cerebellum responsible for
muscle coordination and balance
what’s the medulla oblongata for
controls breathing and heart rate
what are the two scanners used to investigate brain function
CT, PET
what does the CT scanner show
the main structures but not the functions
what do PET scanners show
the structure and function of the brain
why is treating the central nervous system so tricky
because it’s hard to access and dangerous
what is the nervous system made up of
neurones
what does the CNS coordinate
a response
what detects the stimulus
sensory receptors
how is the stimulus info converted
stimulus, receptor, sensory neurone, CNS, motor neurone, effector, response
what is reaction time
the time it takes to react to a stimulus
what are the three neurones
sensory, motor, relay
what is a synapse
the connection between two neurones
what do reflexes do
prevent injury
what does the cornea refract
light into the eye
what does the iris do
control how much light enters the pupil
what does the lens do
refracts light into the retina
what does the retina do
they detect light
what do rods do
sensitive to dim lights but can’t sense colour
what are cones
they r sensitive to different colours but can’t sense dim lights
long sighted is
when someone can’t focus on near objects coz there eye is to short
short sighted is
when someone is unable to focus on distant objects coz the eye is to long
what is colour blindness
when someone can’t tell the difference between certain colours
what is a cataract
a cloudy patch on the lens which stops light from entering the eye
how can you treat cataracts
replace the whole eye w an artificial one
how do you treat colour blindness
you can’t, cone cels can’t be replaced
