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103 Cards in this Set
- Front
- Back
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A reaction takes place on part of the surface of the enzyme called ...?
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The active site.
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All enzymes are made of ...?
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Protein.
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Amoeba is unicellular, this means that it is made up of …?
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Just one cell.
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An alternative name for genetic engineering could be …?
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Genetic modification.
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Animals grow to a fixed size but plants tend to grow …?
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Continuously.
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Apart from growth, why else is mitosis important?
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Repair and replacement of cells, asexual reproduction.
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At high temperatures enzymes become ...?
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Denatured.
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Because each enzyme controls one particular reaction, we say that it is ...?
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Specific.
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Chemicals that speed up reactions are called ...?
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Catalysts.
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Denaturing an enzyme changes the shape of the …?
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Active site.
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Diffusion is the result of what kind of particle movement?
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Random.
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Enzymes work on substances called ...?
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Substrates.
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Explain how Dolly the sheep was created.
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Nucleus taken out of mother’s udder cell and inserted into an egg which had its nucleus removed.
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Give an advantage of being multi-cellular.
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Allows for cell differentiation, greater complexity, greater size.
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Give four differences between arteries and veins.
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Arteries carry blood under high pressure and have a ‘pulse’. Arteries have thicker walls with more elastic. Veins are wider than arteries and have thinner walls. Valves prevent blood flowing backwards in veins.
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Give two disadvantages of plant tissue culture.
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All plants will be affected by a disease or change in environmental conditions, plants will lack genetic variation.
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Growth involves which two processes?
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Cell division/enlargement and cell differentiation.
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How are leaves adapted to gas exchange?
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They are thin and allow gases to diffuse in and out through holes called stomata.
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How are sperm cells adapted to their function?
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Have tail, small size, produced in large numbers.
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How do auxins move through a plant?
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In solution.
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How is auxin distributed in a shoot that is given light from one side?
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Unequally - auxin is moved to shady side.
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How is the placenta adapted to increase the rate of diffusion?
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Thin membrane between foetal and maternal blood, foetal and maternal blood flow in opposite directions.
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In asexual reproduction the offspring have exactly the same genes as the parent. They are said to be ...?
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Clones.
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In mammals, body cells have two copies of each chromosome and are therefore …?
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Diploid.
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In meiosis, chromosome numbers are …?
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Halved
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In plants cell division is restricted to the …?
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Shoot and root tips.
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In this process, particles spread out from a high concentration to a low concentration.
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Diffusion.
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Name one problem of inbreeding.
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Accumulation of harmful characteristics, reduction in variation.
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Name the five stages of human growth.
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Infancy, childhood, adolescence, maturity, old age.
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Name the two main methods of reproduction.
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Asexual reproduction and sexual reproduction.
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Name three ways of cloning plants.
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Grafting and taking cuttings, tissue culture.
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Name two advantages of plant tissue culture.
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Cheap, time-effective, cloned plants have all the good qualities of the parent plant, can be used all the year round.
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Name two commercial uses of plant hormones.
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Weedkillers, rooting powder, fruit ripening, control of dormancy.
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Name two plants that reproduce asexually.
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Spider plant, potato, strawberry.
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One of the main medical uses of genetic engineering in recent years has been …?
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Production of human insulin.
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Only a ..?... amount of enzyme is needed to control a reaction.
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Small.
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Plants cells retain the ability to differentiate but animal cells …?
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Lose it at an early stage.
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Put these four principles of genetic engineering in the correct order: insertion, selection, isolation, replication.
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Selection, isolation, insertion, replication.
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Rooting powders would be used when taking … ?
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Cuttings.
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The acrosome of a sperm contains …?
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Enzymes to digest the cell membrane of the egg cell.
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The best temperature for an enzyme to work is described as the ...?
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Optimum.
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The blood system is often called ...?
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The circulatory system.
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The left ventricle has a very muscular wall because ...?
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It has to pump blood all around the body.
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The liquid part of your blood is called ...?
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The plasma.
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The main method by which plants grow taller is …?
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Cell enlargement.
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The most significant point about meiosis is that it introduces …?
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Variation.
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The muscular lower chambers of the heart are called ...?
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Ventricles.
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The part of the blood responsible for forming a clot.
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The platelets.
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The rate of diffusion is increased by …?
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Short diffusion distance, large concentration difference, greater surface area.
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The red pigment in red cells that carries oxygen.
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Haemoglobin.
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The response of roots to gravity is called …?
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(positive) geotropism.
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The right side of the heart contains blood that is ...?
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Deoxygenated.
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The smallest blood vessels that allow substances to pass to and from the cells.
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The capillaries.
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The surface area/volume ratio of a cell ..?.. with increasing size.
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Decreases.
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The two main types of white cell.
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Phagocytes and lymphocytes.
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The two upper chambers of the heart are called ...?
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Atria.
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The type of cell division that halves the chromosome number.
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Meiosis.
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The type of cell division that produces identical daughter cells.
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Mitosis.
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These give the small intestine a greater surface area for absorption.
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Villi/folded inner surface, microvilli.
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These vessels carry blood away from your heart.
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The arteries.
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These vessels carry blood back to your heart.
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The veins.
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This organ pumps blood around your body.
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The heart.
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This organelle controls the activities of the cell.
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The nucleus.
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This type of membrane allows small molecules (like water molecules) to pass through but not large ones.
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Partially permeable.
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Twins can be described as …?
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Natural clones.
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Two substances that diffuse out of our blood into our cells.
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Nutrients and oxygen.
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What are the arguments against human cloning?
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Many people think that creating human embryos for experimentation and subsequent destruction is unethical.
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What are the complementary base pairs in DNA?
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A-T and C-G.
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What are the functions of the cell membrane?
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To keep the cell as a unit and control the passage of substances into and out of the cell.
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What are the functions of the cell membrane?
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To keep the cell as a unit and control the passage of substances into and out of the cell.
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What are the potential benefits of human cloning?
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Cloned stem cells could be used to treat incurable diseases or create replacement body parts.
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What are the potential benefits of human cloning?
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Cloned stem cells could be used to treat incurable diseases or create replacement body parts.
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What do individual genes code for?
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A particular protein.
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What do plant cells have that animal cells do not have?
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A permanent vacuole, chloroplasts, a cellulose cell wall.
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What do we call the process of cloning plants and growing them in agar jelly?
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Tissue culture.
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What do we call the ways in which some animals and plants have been improved, eg. dairy cattle to produce more milk?
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Selective breeding.
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What does a double circulation mean?
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Blood passes through the heart twice for each circuit of the body.
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What does it mean if a shoot is positively phototropic?
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The shoot grows towards light.
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What effect do auxins have on plant cells?
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They cause elongation.
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What factors can increase the rate of mutations?
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Radiation (UV light, X-rays and gamma rays) and some chemicals.
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What happens to DNA before a cell divides?
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It is copied by enzymes to give two identical copies.
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What happens to gases in the alveolus?
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Oxygen diffuses through the wall of the alveolus into the blood. Carbon dioxide diffuses from the blood in the opposite direction.
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What is a mutation?
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A change in a gene or a chromosome that can cause a change in a characteristic.
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What is a plasmid?
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A circular piece of DNA from a bacterium into which a useful gene can be inserted.
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What is a synapse?
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A small gap between neurones across which a chemical diffuses to transmit an impulse.
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What is a transgenic animal?
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An animal that has had genes from another organism transferred into it.
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What is an alternative name for puberty?
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Adolescence.
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What is embryo transplantation?
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Embryos are split and transplanted into surrogate mothers to give genetically identical offspring.
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What is it important that roots are positively geotropic?
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So that they obtain the maximum possible amount of water and are able to support the plant.
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What is the function of chloroplasts in a plant cell?
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They absorb light energy and carry out photosynthesis.
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What is the gestation period?
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The period from conception to birth during which a foetus develops in the womb.
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What is the hormone produced by the shoot tip that stimulates the shoot to grow?
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Auxin.
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What is the key adaptation of egg cells?
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Large food store.
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What is the role of mitochondria in respiration?
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The release of energy.
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What is the role of the vacuole in plant cells?
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Support and control of water content.
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What types of resistance can genetic engineering be used to transfer into plants?
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Resistance to herbicides, frost damage or disease.
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Where does meiosis occur in humans?
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In the ovaries when making eggs and in the testes when making sperm cells.
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Where is chlorophyll found in plant cells?
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In chloroplasts.
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Which type of cell division is responsible for growth?
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Mitosis.
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Why are sperm produced in large numbers?
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To increase the chances of fertilisation.
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Why does plant tissue culture have to take place in sterile conditions?)
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To prevent contamination by fungi.
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Why is plant cloning easier than animal cloning?
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Because plant cells retain the ability to differentiate.
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Why would a producer want to delay ripening of fruit?
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To ensure that it does not become over-ripe during transport.
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