1. Unit Two The Cell DEFINTIONS Start Alphabetical order
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These definitions are the work of practising teachers - not the SEC - and may have to be adjusted depending on the precise wording of an exam question.
Check SEC marking schemes regularly.
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2. INDEX 2.1 2.3 2.5 Genetics 2.2 2.4 All Cell Structure Cell Continuity
Cell Metabolism and Enzymes
2.4
Cell Diversity
All
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3. 2.1 Cell Structure Eukaryotic Cell* Prokaryotic Cell*
Selectively permeable
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4. 2.2 Cell Metabolism and Enzymes
Metabolism Aerobic respiration
Enzyme Anaerobic respiration
Immobilised Enzyme Fermentation
Bioreactor Diffusion
Photosynthesis Osmosis
Turgor Enzyme Specificity
Enzyme Denaturation Glycolysis
Enzyme Optimum Activity for pH
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5. 2.3 Cell Continuity Cell continuity Chromosome Diploid number
Haploid number
Cancer
Mitosis
Meiosis
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6. 2.4 Cell Diversity Tissue Tissue culture Organ Organ System
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7. 2.5 Genetics Allele Coding dna DNA profiling Dominance Evolution
Fertilisation
Gamete
Gene
Gene Expression
Genetic engineering
Genetic screening
Genotype
Heredity
Heterozygous
Homozygous
Incomplete Dominance
Mutation
Non-coding dna
Phenotype
Recessive
Species
Transcription
Translation
Variation
Mendel’s 1st Law[Segregation]
Mendel’s 2nd Law[Ind.Assortment]
Linkage
Sex Linkage
Non-nuclear Inheritance
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8. All Back to Start Aerobic respiration Allele Anaerobic respiration
Bioreactor
Cancer
Cell continuity
Chromosome
Coding dna
Diffusion
Diploid number
DNA profiling
Dominance
Enzyme
Enzyme Denaturation
Enzyme Optimum Activity for pH
Enzyme Specificity
Eukaryotic Cell*
Evolution
Fermentation
Metabolism
Mitosis
Mutation
Non-coding dna
Non-nuclear Inheritance
Organ
Organ System
Osmosis
Phenotype
Photosynthesis
Prokaryotic Cell*
Recessive
Sex Linkage
Selectively permeable
Species
Tissue
Tissue culture
Transcription
Translation
Turgor
Variation
All
Fertilisation
Gamete
Gene
Gene Expression
Genetic engineering
Genetic screening
Genotype
Glycolysis
Haploid number
Heredity
Heterozygous
Homozygous
Immobilised Enzyme
Incomplete Dominance
Linkage
Meiosis
Mendel’s 1st Law[Segregation]
Mendel’s 2nd Law[Ind.Assortment
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9. The release of energy from carbohydrate using oxygen
Aerobic respiration
The release of energy from carbohydrate using oxygen
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10. An alternative form of a gene
Allele
An alternative form of a gene
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11. Anaerobic respiration
The release of energy from carbohydrate without using oxygen.
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12. vessel in which products are made by cells (or organisms) (or enzymes)
Bioreactor
vessel in which products are made by cells (or organisms) (or enzymes)
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13. A growth resulting from abnormal and uncontrolled mitosis
Cancer
A growth resulting from abnormal and uncontrolled mitosis
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14. Process whereby cells develop from pre-existing cells.
Cell continuity
Process whereby cells develop from pre-existing cells.
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15. Chromosome A structure made of DNA and protein which can be inherited.
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16. Coding dna
That part of the chromosome which carries the information to make a protein
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17. Diffusion
The movement of [gas or liquid] molecules from a region of higher concentration to a region of lower concentration.
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18. Chromosomes in pairs (two sets of chromosomes.)
Diploid number
Chromosomes in pairs (two sets of chromosomes.)
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19. DNA profiling examining DNA / for a pattern or band / to compare
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20. One allele masks the expression of the other.
Dominance
One allele masks the expression of the other.
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21. Enzyme
Biological catalyst
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22. Permanent Loss of (enzyme) function (or activity)
Enzyme Denaturation
Permanent Loss of (enzyme) function (or activity)
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23. Enzyme Optimum Activity for pH
the pH at which an enzyme works best
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24. Enzyme Specificity
[The concept that]An enzyme will combine (usually) with only one substrate to form a product.
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25. Cells which have a nucleus and other membrane bound organelles.
Eukaryotic Cell*
Cells which have a nucleus and other membrane bound organelles.
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26. Evolution
(Inheritable) change within a population (or species) / in response to change in the environment / by natural selection/over time
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27. Anaerobic respiration
Fermentation
Anaerobic respiration
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28. The fusion of 2[haploid] gametes to form a [diploid] zygote
Fertilisation
The fusion of 2[haploid] gametes to form a [diploid] zygote
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29. A haploid sex cell which is capable of fusion
Gamete
A haploid sex cell which is capable of fusion
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30. A unit of DNA which codes for the production of a specific protein
Gene
A unit of DNA which codes for the production of a specific protein
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31. The process of using the information on the gene to make a protein
Gene Expression
The process of using the information on the gene to make a protein
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32. Manipulation or alteration of genes
Genetic engineering
Manipulation or alteration of genes
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33. Genetic screening
Testing (people) for the presence of a (specific) gene or
To establish presence or absence of gene(s)
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34. The genetic make-up of an individual
Genotype
The genetic make-up of an individual
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35. The process of breaking down glucose into pyruvic acid.
Glycolysis
The process of breaking down glucose into pyruvic acid.
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36. Having one set of chromosomes
Haploid number
Having one set of chromosomes
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37. The passing on of traits from parent to offspring by means of genes
Heredity
The passing on of traits from parent to offspring by means of genes
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38. Has different alleles [for a trait]
Heterozygous
Has different alleles [for a trait]
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39. Has identical alleles [for a trait]
Homozygous
Has identical alleles [for a trait]
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40. Immobilised Enzyme
A biological catalyst which is fixed to an inert material by chemical or physical means.
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41. Neither allele masks the expression of the other.
Incomplete Dominance
Neither allele masks the expression of the other.
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42. Genes located on the same chromosome[ are said to be linked]
Linkage
Genes located on the same chromosome[ are said to be linked]
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43. Meiosis
A form of nuclear division in which one (diploid) nucleus divides to form 4 different (haploid) (daughter) nuclei.
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44. Mendel’s 1st Law[Segregation]
Traits are controlled by pairs of alleles which separate at gamete formation. Each gamete carries only one allele for each trait
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45. Mendel’s 2nd Law[Ind.Assortment]
During gamete formation each member of a pair of alleles may combine randomly with either of another pair
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46. All the chemical reactions that occurs in organisms
Metabolism
All the chemical reactions that occurs in organisms
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47. Mitosis
A form of nuclear division in which one nucleus divides to form 2 identical (daughter) nuclei.
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48. Change in the genetic make up
Mutation
Change in the genetic make up
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49. Non-coding dna
That part of the chromosome which does not carry the infomation to make a protein
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50. Non-nuclear Inheritance
DNA apart from that found in the nucleus[e.g. mitochondria] that is passed on to the next generation
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51. A group of tissues that work together.
Organ
A group of tissues that work together.
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52. A group of organs that work together
Organ System
A group of organs that work together
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53. Osmosis
The movement of water molecules from a region of high water concentration to a region of low water concentration across a selectively permeable membrane or
The movement of water molecules along a concentration gradient across a selectively permeable membrane .
Movement of water molecules from a more dilute solution to a more concentrated solution across a selectively permeable membrane
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54. physical appearance of an organism
Phenotype
physical appearance of an organism
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55. Photosynthesis
Process where plants make carbohydrate using (sun)light energy (CO2, water and chlorophyll).
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56. Cells which DO NOT have a nucleus and other membrane bound organelles.
Prokaryotic Cell*
Cells which DO NOT have a nucleus and other membrane bound organelles.
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57. Allele whose expression is masked by dominant allele
Recessive
Allele whose expression is masked by dominant allele
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58. Gene located on X- chromosome or on Y-chromosome
Sex Linkage
Gene located on X- chromosome or on Y-chromosome
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59. Selectively Permeable
Only some substances are allowed through
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60. Organisms capable of interbreeding and producing fertile offspring.
Species
Organisms capable of interbreeding and producing fertile offspring.
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61. Tissue Group of similar cells. Back to Index subsection
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62. Tissue culture Cells grown on (or in) medium or
cells grown outside organism
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63. The process of producing mRNA using DNA as a template.
Transcription
The process of producing mRNA using DNA as a template.
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64. The process of making a protein using the mRNA code as a template
Translation
The process of making a protein using the mRNA code as a template
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65. The state of fullness in a plant cell due to the intake of water.
Turgor
The state of fullness in a plant cell due to the intake of water.
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66. Difference between members of species or population
Variation
Difference between members of species or population
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67. The
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