Topic 2 Flashcards
Adult Stem Cells
Stem cells that can differentiate into a limited range of cell types
Asexual Reproduction
A form of reproduction involving a single parent that creates a genetically identical offspring
Axon
A long fibre that conducts nerve impulses away from the cell body
Cancer
A non-communicable disease caused by changes in the cell that lead to uncontrolled growth
Cataract
A cloudy patch that forms on the lens preventing light from entering the eye
Cell Differentiation
The process where a cell becomes specialised for its function
Cell Elongation
The process which cells expand and enlarge enabling the growth of a plant.
Central Nervous System
The brain and spinal cord
Cerebellum
The region of the brain the coordinates muscles and non-voluntary movement. (Eg: Balance and Posture)
Cerebral Hemisphere
One half of the cerebellum, each half controls corresponding half of the body
Cerebrum
The largest region of the brain made of 2 hemispheres. Responsible for movement, memory, intelligence, language and vision.
Chromatid
One ‘arm’ of a replicated chromosome
Chromosome
A long coiled molecule of DNA that carries genetic information in the form of genes
Colour Blindness
A deficiency of the eye making it difficult to distinguish between colours.
Cone Cells
Cells found in the retina that are sensitive to high light intensity (bright lights) and detect different colours.
Cornea
The transparent out layer that reflects light entering the eye.
CT Scan
A imaging technique that uses X-Rays to make a detailed imagine of internal organs.
Dendrites
Short, branched extensions of dendrons that provide large surface areas to receive nervous impulses from other neurones
Dendron
Branched extension of nerve cell body that connects to other neurones and carries impulses towards the body
Diploid Cell
A cell that contains 2 copies of each chromosome
Effector
An organ, tissue or cell that produces a response to a stimulus
Embryonic Stem Cells
Stem cells found very early in embryos that are unspecialised and capable of differentiating into any cell type
Eye
A sense organ containing receptors sensitive to light intensity and colours
Growth
An increase in mass or size
Haploid Cell
A cell that contains a single copy of each chromosome
Iris
A pigmented ring of muscles that controls the size of the pupil to alter how much light enters the eye
Lens
A transparent biconvex structure that refracts light focusing it onto the retina.
Long-Sightedness
A defect of the eye where nearby objects appear out of focus due to convergence of light rays behind the retina. This occurs when the eyeball is too short or the less is less elastic. This is fixed using a convex lens.
Medulla Oblongata
The region of the brain that controls unconscious activity such as breathing and heart rate
Meristem Tissue
Plant tissues containing undifferentiated stem cells
Motor Neurone
A neurone that carries nerve impulses from the CNS to the effectors.