Flashcards in Topic 2 - Cells and Control Deck (43):
In human cells, what is a chromosome?
a structure found in nuclei, containing a DNA molecule
What type of cell division forms two identical daughter cells?
In which stage of the cell cycle are the chromosomes duplicated?
In which stage of the cell cycle, at the end of mitosis, does the one cell divide into two?
What term describes a cell that has two sets of chromosomes?
Where are plant meristems found?
tips of plant shoots and roots [also just inside bark of trees]
What happens in a plant meristem?
Cells divide rapidly by mitosis as the plant grows
What happens during cell differentiation?
Cells develop special features that help them carry out a particular function.
Why is cell differentiation important to plants and animals?
Specialised cells are more effective at carrying out different functions in the body.
A root hair cell is a specialised cell. What is its function?
to absorb water and dissolved mineral salts from the soil
How is a root hair cell specialised to carry out its function?
It has a long extension into the soil that increases the surface area for absorption
Explain how one specialisation of a xylem vessel helps it carry out its function.
any one from: thickened wall to prevent collapse of tube/withstand pressure of water; no cell cytoplasm and lost cell walls to form long tubes through which water flows up the plant; small holes in thick cell wall so water can pass into and out of the vessel from surrounding cells
Name one feature, other than mass, that could be measured to show growth in a plant.
any suitable measure that will show change over time, such as: height, tree girth, leaf area, number of leaves
Name the type of cell division that cells use to make identical copies of themselves.
What type of cell has the ability to differentiate into specialised cells?
In what organ system would you find nerve cells?
the nervous system
Are nerve cells diploid or haploid?
What part of a nerve cell contains chromosomes?
What part of a nerve cell makes proteins?
Nerve cells require a lot of energy. What cell structure would you expect them to have a lot of?
What is a nerve cell specialised to do?
carry electrical signals/impulses
List your senses.
touch, hearing, sight, taste, smell, balance, temperature and plenty of others
State the name of one organ in the nervous system.
brain, spinal cord or nerves or a named sense organ
Triple Only- What type of cells is the brain mainly made up of?
neurones, nerve cells
Triple Only-What part of the brain controls our senses and emotions?
Triple Only-State one thing that the cerebellum controls.
balance, posture or fine motor movements)
Triple Only-Where is the medulla oblongata in relation to the spinal cord?
at the top of the spinal cord
Triple Only-What part of the brain controls the rate of the heart?
Triple Only-What part of the brain stores our memories?
Triple Only-Apart from bundles of neurones, what else does a nerve contain?
Triple Only-What name is given to an electrical signal transmitted by a neurone?
Triple Only-What part of the brain controls the rate of breathing?
Triple Only-Which cerebral hemisphere receives information from the right eye?
What type of cells detect stimuli?
In which sense organ would you find receptor cells that detect light waves?
What are the electrical signals used in the nervous system called?
List, in order, the organs that an impulse goes through from the hand to the brain.
nerve(s), spinal cord
What are the two long ‘arms’ of a sensory neurone called?
dendron and axon
List, in order, the parts of a sensory neurone that an impulse goes through.
dendrite, dendron, axon, axon terminal
Why are sensory neurones so long?
to carry impulses quickly over long distances
What is the name of the fatty sheath that surrounds dendrons and axons?
What does the myelin sheath do?
speeds up transmission of impulses, insulates neurones from each other