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46 Cards in this Set
- Front
- Back
What could be the possible causes of extinction? |
A single catastrophic event New diseases New predators Changes to the environment |
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What does glandular tissue do? |
Secrete substances |
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What does muscular tissue do? |
Contract to bring about movement. |
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What does epithelial tissue do? |
Covers and protects the cells underneath. |
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What are the five components of an animal cell and what are their functions? |
Nucleus - controls cell function, contains dna. Ribosomes - synthesis proteins Mitochondria - release energy from respiration. Cell Membrane - controls what goes in and out of the cell. Cytoplasm - where chemical reactions occur. |
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What are enzymes? |
Proteins that catalyse chemical reactions in the body. |
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What is the job of bile in the digestive system? |
It neutralises stomach when the enter the small intestine. It also emulsifies fats allowing lipase to break it down. |
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What is a phenotype? |
A physical characteristic controlled by a gene. |
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What are genotypes? |
A description of the alleles for a gene |
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Define homozygous and heterozygous. |
Homozygous - having two of the same allele Heterozygous - having two different alleles |
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Why was Gregor Mendel's theory not accepted? |
He was not well respected and there was insignificant evidence of the mechanism. |
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What is an allele? |
A different type of gene. |
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What is a gene? |
A section DNA that codes the amino acids for a particular protein. |
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What is DNA? |
A long molecule that contains genetic information. |
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What are the 3 factors that affect the rate of photosynthesis? |
CO2 concentration Temperature Light intensity |
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When exercising, why does our heart rate, breathing rate and breathing depth increase? |
These changes occur to increase the flow of oxygen-rich blood to the working muscles for respiration and the release of energy. |
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What are the three enzymes AQA states should be known by all candidates and what do they do? |
-Amylase breaks down starch into glucose -Protease breaks dowb proteins into amink acids -Lipase breaks down fats into fatty acid and glycerol |
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Describe the effects of pH on the rate of reaction of enzymes in the stomach. |
As you increase the pH, the rate of reaction increases to an optimum of between pH 1-2. Past this point the rate decreases as enzymes are denatured. |
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What type of cell division is used for asexual reproduction? |
Mitosis |
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What is diffusion? |
The spreading out of fluid particles from and area of high concentration to an area of low concentration. |
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How do we get new species? |
Isolation due to geographical change. Each area has a different range of alleles and different conditions. Each set of animals undergos natural selection to become adapted to their environment. Over many years, the animals become so different they can no longer breed to produce fertile offspring creating new species. |
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What factors affect the distribution of organisms? |
Temperature Light intensity Food availability Water availability Oxygen and CO2 concentrations |
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What are hormones made from? |
Proteins. |
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Where is bile stored? |
The gall bladder. |
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What happens when temperatures are too high for enzymes? |
Their active sites are denatured so substrates no longer fit. |
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What is the energy from respiration used for in animals? |
Regulating temperature Bringing about muscle contractions for movement Building larger molecules from snaller ones. |
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When do we respire anaerobically and what is produced? |
We respire anaerobically with insufficient oxygen and lactic acid is produced when we do. |
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What is oxygen debt? |
The extra oxygen taking in after exercise. |
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How do plants use glucose? |
Producing proteins (with nitrates) For storage as starch Making cellulose |
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Why are stem cells useful? |
They can differentiate into any type of cell as they are unspecialised. |
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What are the features of your digestive system? |
Mouth Stomach Small intestine Large intestine Pancreas Liver |
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What is a dominant allele? |
An allele that will express a characteristic with only one copy of it. |
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Where do we get stem cells from? |
Bone marrow or embryos. |
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Are the hard or soft parts of an animal easiest to fossilise? |
Hard parts. |
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What eat dead animals and prevent fossilisation? |
Scavengers |
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What is the shape of a DNA molecule? |
A double helix |
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What name is given to the process which can identify people by analysing their genes? |
DNA fingerprinting |
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What chemical are genes made from? |
DNA |
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Is polydactyl caused by a dominant or recessive allele? |
Dominant |
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Some early fossils have been destroyed by what kind of activity? |
Geological/tectonic |
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What is the process in which new species are formed? |
Speciation |
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Generally, all humans have unique DNA, the only exceptions to this are...? |
Identical twins |
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What enzyme turns glucose into fructose? |
Isomerase |
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What is a person called when they only have one copy of a recessive allele? |
A carrier. |
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What is the process by which fossils are made? |
Fossilisation |
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Fossilisation can only occur when the conditions for what process are absent? |
Decay |