SB2 Flashcards
What is mitosis a type of
Cell division
What are the stages of mitosis
IPMATC
INTERPHASE- the cell duplicates its DNA
PROPHASE- membrane around nucleus breaks down
METAPHASE- chromosomes line up in centre of cell
ANAPHASE- cell fibres pull chromosomes apart
TELOPHASE- the nucleus divides
CYTOKINESIS- two identical daughter cells form
Define cell differentiation
The process of when a cell becomes specialised
Define growth
An increase in size or mass
Define cell elongation
Cell expands making plant grow
What are undifferentiated cells called
Stem cells
Where are stem cells found
Human embryos
Bone marrow
Disadvantages of using stem cells
Rumour development
Rejection
Disease transmission
What does the cerebellum control and where’s it found
Muscles coordination and balance
Behind spinal cord
What does the cerebral cortex control and where’s it found
Largest part of brain
Two halves
Movement memory language vision intelligence
What does the medulla oblongata control and where’s it found
Bottom near spinal cord
Controls breathing and heart rate
What are the two scanners to investigate brain function
PET scan
CT scan
How/what does the CT scan :
Work
Show
Uses xrays to produce image of brain
Shows structure of brain
Can show a damaged brain and identify the area
How/what does the PET scan :
Work
Show
Radioactive chemicals To show what part of the Brian is active
Very detailed
Can show structure and function at the same time
What does the CNS stand for
Central nervous system
What is the CNS made of
Neurones which go to all parts of the body
What are sensory receptors
Cells that can detect a change in the environment
How does the CNS coordinate a response
Stimulus Receptor Sensory neurone CNS Motor neurone Effector Response
Sensory neurone context
One long dendron
Carries nerve impulses
From receptor cells to cell body
One short axon carries nerve impulses from the cell body to the CNS
Motor neurone context
Many short
Carries nerve impulses
From CNS to the cell body
One Long axon carries nerve impulses from cell body to effector cell
Relay neurone Context
Many short dendrites
Carries nerve impulses
Sensory neurones to cell body
An axon carries nerve impulses from the cell body to motor neurones
What do neurones transfer information as
Electrical impulses
Define synapes
Connection between two neurones
Define reflexes
Rapid responses to stimuli
In which order do the neurones act
Sensory
Relay
Motor
What does the cornea do
Bends light into the eye
What does the iris do
Controls how much light enters pupil
What does the lens do
Bends light focusing it onto retina
What does the retina do
Detect light through receptor cells called rods and cones
Advantages and disadvantages of rod cells
ADVANTAGES
sensitive in dim light
DISADVANTAGES
Can’t sense colour
Advantages and disadvantages of cones
ADVANTAGES
sensitive to different colours
DISADVANTAGES
not good in dim light
What does the optic nerve do
Carries electrical impulses about information from the light from receptor cells to brain
What is cataract
A cloudy patch on the lens
