Biology 3 Keywords Flashcards Preview

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Flashcards in Biology 3 Keywords Deck (80):
1

Acrosome

Cap-like structure on the head of a sperm cell that produces enzymes used to penetrate an egg.

2

ADH (antidiuretic hormone)

A hormone made by the pituitary gland that causes the kidneys to retain water in the body.

3

African Eve

A woman who lived in Africa between 130 000 and 200 000 years ago, and passed on mtDNA to all humans living today.

4

Agrobacterium Tumefaciens

A bacterium used as a vector in genetic modification.

5

Antigen

A protein that white blood cells recognise as foreign, for example, on the surface of a bacterium.

6

Ardi

The name given to the individual of a human-like species that lived 4.4 million years ago, whose fossil bones were discovered in Ethiopia.

7

B Lymphocyte

A type of lymphocyte that produces antibodies.

8

Bacillus Thuringiensis

A bacterium that produces a substance that is toxic to insects that destroy crop plants. Some crop plants have been genetically modified with a gene from this bacterium.

9

Biological Clock

A timing mechanism in the body that helps to control various rhythms, such as sleeping and waking.

10

Bt Toxin

A poison produced by a bacterium (Bacillus thuringiensis) when eaten by insects. The gene for the toxin has been transferred to some crop plants to reduce damage by insect pests.

11

Choice Chamber

A device that offers small invertebrates such as woodlice two or more contrasting environments. The different conditions provide a stimulus to which the invertebrates respond.

12

Chymosin

A protein-digesting enzyme used to make cheese that can be produced by genetically modified bacteria or yeast.

13

Conventional Breeding

Producing offspring using the natural technique of cross-breeding.

14

Convoluted Tubule

A part of the kidney tubule where glucose and other useful substances are reabsorbed into the blood.

15

Corpus Luteum

A structure that develops in an ovary after an egg has been released, which secretes progesterone.

16

Courtship Behaviour

Actions that help male and female organisms to attract one another, and to maintain the bond between them.

17

DNA Ligase

An enzyme that joins two DNA molecules together.

18

Evolutionary Strategy

A process that affects how a species changes over time and spreads, such as parental care that helps offspring to survive for longer.

19

Exponential Growth

When the growth rate of a population is proportional to the population's current value.

20

Fermentation

When microorganisms break down large molecules, using enzymes to produce different substances, including foodstuffs and drugs. For example, the conversion of glucose into ethanol (alcohol), using enzymes found in yeast.

21

Fermenter

A container in which microorganisms are cultured to produce a useful substance on a large scale - the product is collected from the solution in which the microorganisms have grown.

22

Follicle

Fluid-filled sac in the ovary that contains the egg.

23

FSH (Follicle Stimulating Hormone)

A hormone produced by the pituitary gland, which causes eggs to mature in the ovaries.

24

Fusarium

A type of fungus that is grown in fermenters to produce mycoprotein as a food source.

25

Genetic Modification

Adding a gene for a particular characteristic from one organism into another so that the second organism shows the characteristic.

26

Germinate

A process in which a seed begins to grow into a young plant.

27

Glomerulus

A network of blood capillaries in a kidney.

28

Haemophilia

A disorder of blood clotting, caused by a recessive allele on the X chromosome.

29

Hormone

Chemical messengers that are made in one part of the body and are carried in the blood to other parts which they affect, such as melatonin which changes the actions of parts of the body so we feel sleepy.

30

Hybridoma

A cell made by using a lymphocyte with a cancer cell.

31

Insulin

The hormone which decreases blood glucose concentration. Used in treatment of Type 1 diabetes.

32

Invertase

An enzyme (also known as sucrose) that catalyses conversion of sucrose into glucose and fructose.

33

IVF (In Vitro Fertilisation)

Fertilising an egg by placing it in a sterile container and then adding sperm.

34

Kidney

One of the organs in the abdomen that removes urea and extra water from the blood, producing urine.

35

Lactase

An enzyme that catalyses the breakdown of lactose (milk sugar). The enzyme is produced by the digestive system and by bacteria used in yoghurt manufacture. lactose-intolerant individuals do not produce this enzyme and cannot digest lactose.

36

Lactic Acid

The substance that gives the sour taste to yoghurt, produced when certain bacteria ferment the sugar lactose in the absence of oxygen.

37

Lactose

A sugar found in milk that is converted to lactic acid in the manufacture of yoghurt.

38

LH (Luteinising Hormone)

A hormone produced by the pituitary gland, which causes ovulation.

39

Lipase

An enzyme that catalyses the breakdown of lipids (fats and oils).

40

Lucy

The name given to the individual of a human-like species that lived 3.2 million years ago, whose fossil bones were discovered in Ethiopia.

41

Lymphocyte

A type of white blood cell that produces antibodies.

42

Memory Lymphocyte

A lymphocyte that remains in the blood for a long time after an infection or vaccination.

43

Menstruation

The breakdown and loss of the lining of the uterus, at the start of a woman's menstrual cycle.

44

Mitochondrial DNA

The DNA found inside mitochondria, which is passed by the mother to all offspring without any mixing; sons do not pass down their mother's mtDNA to their children.

45

Mitochondrion (Plural Mitochondria)

The site of cellular respiration where glucose is broken down using oxygen to release energy, which is needed for reactions in the cell.

46

Monoclonal Antibodies

Many identical antibodies.

47

Negative Feedback

A control mechanism in which a change in a factor causes an action that reverses the change.

48

Oestrogen

A hormone produced by the ovaries, important in the menstrual cycle.

49

Optimum pH

The pH at which an enzyme's rate of reaction is greatest, or at which a population of microorganisms grows most rapidly.

50

Optimum Temperature

The temperature at which an enzyme's rate of reaction is greatest, or at which a population of microorganisms grows most rapidly.

51

Pasteurisation

When foods, such as milk, are heated briefly to kill the bacteria in them.

52

Pathogen

An organism (usually a microorganism such as bacterium or virus) that causes disease.

53

Pheromone

A substance produced by one organism that diffuses into the environment and causes responses in another organism (a chemical signal).

54

Photoperiodism

The way in which living organisms respond to changes in daylength.

55

Pituitary Gland

Gland at the base of the brain that secretes many different hormones, including FSH and LH.

56

Plant Chemical Defence

Some plants have evolved to defend themselves against attack from herbivores by producing toxic compounds; some insects have co-evolved an adaptation to allow them to eat the plant.

57

Pollination

Transfer of pollen (the male gamete in plants) from one flower to another, enabling fertilisation.

58

Primary Response

The way in which the immune system responds on the first occasion that a particular pathogen enters the body.

59

Progesterone

A hormone produced by the ovaries and placenta, which helps to maintain the thick lining of the uterus.

60

Recombinant DNA Technology

Genetic modification; the addition of new DNA to an organism's cells.

61

Renal Artery

An artery that delivers blood to the kidneys.

62

Renal Vein

A vein that carries blood away from the kidneys.

63

Resazurin Dye

Dye used as a qualitative test for the presence of significant numbers of bacteria in milk, thereby checking whether it is fit for sale.

64

Restriction Enzyme

An enzyme that cuts DNA molecules into pieces.

65

Saccharomyces Cerevisiae

A species of yeast, a single-celled fungus, used in biotechnology, for example, to cultivate the enzyme invertase.

66

Saturated

A molecule which contains only single bonds between the carbon atoms and has the maximum possible number of atoms attached to the carbon chain.

67

Secondary Response

The way in which the immune system responds on the second occasion that a particular pathogen enters the body.

68

Selective Reabsorption

Taking back useful substances into the blood, from the fluid inside a nephron.

69

Sterilise

To destroy bacteria, viruses, mould and pests such as insects on an object. It can be carried out using radioactive sources.

70

Sticky End

A length of DNA with only one strand, that will easily join with other pieces.

71

Sucrase

An enzyme (also known as invertase) that converts sucrose to glucose and fructose.

72

Transgenic Plant

A plant containing genes that have been taken from another species.

73

Unsaturated

A molecule which contains one or more double bonds between the carbon atoms, allowing extra atoms to be added on to the carbon chain.

74

Urea

A waste product produced in the liver from excess amino acids.

75

Ureter

One of the tubes that carry urine from the kidneys to the bladder.

76

Urethra

The tube that carries urine from the bladder to the outside of the body.

77

Urinary System

The body system that produces and removes urine, including the kidneys, ureters, bladder and urethra.

78

Urine

A fluid produced by the kidneys, containing urea and other waste substances dissolved in water.

79

Vaccine

A substance containing dead or weakened pathogens (or parts of them), introduced into the body to make a person immune to that pathogen.

80

Vector

A 'go-between' that is used in genetic modification, to transfer genes from the cells of one organism to another.