Biology 1 Keywords Flashcards Preview

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Flashcards in Biology 1 Keywords Deck (235):
1

Acquired Characteristic

A characteristic that is changed by the environment rather than inherited from your parents.

2

Adaptation

Organisms have certain characteristics that allow them to survive in particular places. These characteristics are called adaptations.

3

Addicted

When the body is dependent on a drug and doesn't work properly without it.

4

Allele

Every gene comes in different types called alleles. So a gene for eye colour may come in a 'blue type' allele and a 'brown type' allele.

5

Amphibians

Vertebrates that have moist, permeable skin and lay jelly-coated eggs in water.

6

Antibacterial

Antibiotic that kills or slows the growth of bacteria.

7

Antibiotic

Substance that can kill or slow the growth of micro-organisms.

8

Antifungal

Antibiotic that kills or slows the growth of fungi.

9

Antiseptic

Substance that is used to top the spread of pathogens.

10

Autotrophic Feeding

Make food from small molecules using an energy source, such as light in photosynthesis.

11

Auxin

Plant hormone that affects the growth and elongation of cells in plants.

12

Axon

The long extension of a neurone that carries an impulse away from the cell body towards other neurones.

13

Bacteria

Simple organisms consisting of one cell that does not contain a nucleus (singular: bacterium).

14

Bacterium

Microscopic organism, some kind of which are pathogens, such as Salmonella (plural: bacteria).

15

Binomial System

System of naming organisms using two Latin words.

16

Biomass

The total mass in living organism, using shown as the mass after drying.

17

Birds

Vertebrates that have lungs, feathers and beaks, and lay hard-shelled eggs.

18

Blackspot Fungus

Fungus that damages roses and is killed by sulfur dioxide in the air.

19

Blood Glucose Regulation

The control of the concentration of glucose in the blood by the body.

20

Blood worm

Aquatic species that is an indicator of polluted water.

21

Body Mass Index (BMI)

Estimate of how healthy a person's mass is for their height.

22

Carbon Cycle

A sequence of processes by which carbon moves from the atmosphere, through living and dead organisms, into sediments and into the atmosphere again.

23

Carbon Monoxide

A toxic gas (CO), it is found in tobacco smoke that replaces oxygen in the blood, and so reduces the amount of oxygen carried around the body.

24

Carcinogen

Something that causes cancer, such as tar in tobacco smoke.

25

Cell Membrane

Thin layer around a cell that controls what goes into and out of a cell.

26

Cell Wall

Outer stiff part of some cells that helps to support a cell. Plant walls are made out of cellulose.

27

Central Nervous System (CNS)

The spinal cord and brain. These two organs form the main part of the nervous system, processing and controlling the transmission of electrical impulses.

28

Characteristic

The features of an organism.

29

Chemical Defence

Preventing attacks by the use of chemicals. For example, many plants produce chemicals that taste unpleasant and this puts herbivores off eating them.

30

Chemosynthetic Bacteria

Bacteria that get the energy they need to make their food from breaking down chemicals; they are producers.

31

Chloroplast

Green disc found in plant cells, which is used to make food for the plant using photosynthesis.

32

Chordata

Animals that have a supporting rod along the length of their body. All vertebrates belong to this group. (Also known as Chordates).

33

Chromosomes

A long thread of a molecule called DNA. Each chromosome contains a series of genes along its length.

34

Cirrhosis

Damage to the liver caused by drinking large amounts of alcohol over a long time.

35

Classification

The process of sorting organisms into groups based on their characteristics.

36

Cleaner Fish

Fish that eat dead skin and parasites from the skin of other fish.

37

Clinically Obese

When someone is very overweight for their height to an extent that has been shown by doctors to cause health problems. For adults this is defined as having a BMI of over 30.

38

Competition

When organisms need the same resources as each other, they struggle against each other to get those resources.

39

Concentration

The amount of a substance dissolved in a certain quantity of liquid (e.g. g/cm3).

40

Consumer

An animal, because it consumes other organisms.

41

Continuous Variation

When a variable can have any numerical value. Human height is a continuous variable.

42

Criterion

Rule or test that can be used to judge how to make a fair decision (plural: criteria).

43

Cutting

Part of a plant (normally a leaf or stem) from which a new plant can be grown.

44

Cystic Fibrosis (CF)

A genetic disorder caused by inheriting two copies of a recessive allele. It causes thick mucus to collect in the lungs, making breathing difficult, and also stops food being digested very well.

45

Cytoplasm

Jelly-like part inside a cell where the cell's activities happen.

46

Decay

Process in which complex substances in dead plant and animal biomass are broken down by decomposers into simpler substances.

47

Decompose

To break down larger molecules into smaller molecules.

48

Decomposer

Organism that feeds on dead material, causing decay.

49

Dendrite

Many fine extensions of a dendron of a neurone that collect impulses from other neurones or receptors.

50

Dendron

Extension of a neurone that carries the impulses to the cell body. It ends in many dendrites and is usually shorted than an axon.

51

Denitrifying Bacteria

Bacteria that break down more complex nitrogen compounds into simpler ones, such as nitrates to nitrites, or nitrites to ammonia.

52

Depressant

Substance that slows down the activity of neurones in the brain.

53

Dermis

The layer of skin below the surface epidermis where nerve endings, blood vessels and other structures are found.

54

Diabetes

Disease in which the body cannot control blood glucose concentration at the correct level.

55

Digest

Break down, as when our digestive system breaks up food into simpler substances.

56

Discontinuous Variation

When a variable cannot have a continuous range of options, for example days of the week, shoe sizes.

57

DNA

Deoxyribose nucleic acid. Chemical that makes up genes and chromosomes; the instructions for a cell's growth and activity.

58

Dominant Allele

Version of a gene (allele) that will always have an effect (as opposed to a recessive allele, whose effect will not be seen if a dominant allele is present).

59

Donor

Person who gives, such as the person who gives an organ for transplant into another person.

60

Drug

A substance that changes the way the body works.

61

Effector

Muscle or gland in the body that performs an action when an impulse from the nervous system is received.

62

Egg Cell

Another term for ovum.

63

Endocrine Gland

A gland that makes and releases hormones.

64

Environmental Variation

Differences between the characteristics of organisms caused by their environment.

65

Erector Muscle

Muscle in the dermis of the skin that raises a body hair.

66

Ethical Decision

Decision about what is right or wrong.

67

Eutrophication

The addition of chemicals to water, such as nitrates and phosphates, which encourages plant growth.

68

Evolution

Gradual change over a period of time.

69

External Fertilisation

When fertilisation happens outside the body of an animal.

70

Extinction

The dying out of a species so that it no longer exists.

71

Faeces

Waste material from food which was now absorbed by the body.

72

Family

A classification group that contains genera with similar characteristics.

73

Family Pedigree Chart

A chart showing which members of a family suffer from a genetic disorder.

74

Feeding Relationship

The relationship between two organisms where one eats the other.

75

Fertile

Able to produce offspring.

76

Fertilser

Chemical compounds added by farmers to soil to increase the rate of growth of crops.

77

Fish

Vertebrates that have wet scales, gills and lay jelly-coated eggs.

78

Food Chain

A diagram to show, with arrows, the flow of food and energy from a producer to the animal that eats that producer, the animal that eats that animal, and so on.

79

Food Web

A diagram of interlocked food chains that show how the feeding relationships in one habitat are interdependent.

80

Freshwater Shrimp

Aquatic species that is an indicator of clean water.

81

Fungus

Organism that feeds on dead or decaying material, such as athlete's foot fungus (plural:fungi).

82

Gamete

Cell that contains only half the normal number of chromosomes. It joins with another sex cell during fertilisation, to produce a fertilised egg cell, which contains a full set of chromosomes.

83

Gene

A section of DNA that carries the instructions for a characteristic.

84

Genetic Cross Diagram

Diagram showing how alleles in two parents may form different combinations in the offspring, when their parents reproduce.

85

Genetic Disorder

A disease caused by alleles.

86

Genetic Variation

Variation in characteristic caused by the instructions within cells.

87

Genotype

The alleles for a certain characteristic that are found in an organism.

88

Genus

A classification group that contains species with similar characteristics (plural: genera).

89

Geotropism

Tropism in response to gravity.

90

Germinate

When a seed starts to grow a shoot and a root.

91

Gibberellins

Set of plant hormones that can cause seeds to germinate, and flowers and fruits to form.

92

Gland

A part of the body that makes substances and then releases them.

93

Glucagon

Hormone released by endocrine glands in the pancreas, which increases the blood glucose concentration by causing cells, especially those in the liver, to turn glucose into glycogen.

94

Glucose

A sugar, which is produced by the digestion of carbohydrates and is needed by cells for respiration.

95

Glycogen

A storage material made from glucose.

96

Habitat

The place an organism lives in, for example woodland.

97

Hallucinogen

Substance that distorts sense perception.

98

Heterotrophic Feeding

Getting food by eating and digesting the tissues of other organisms.

99

Heterozygous

If both alleles for characteristic are different, the organism is heterozygous for that characteristic.

100

Homeostasis

Controlling the internal environment of the body at stable levels.

101

Homeotherm

An animal that keeps its body temperature more constant than the surroundings, and often warmer, by releasing heat from reactions in its body.

102

Homozygous

If both alleles for a characteristic are the same, the organism is homozygous for that characteristics.

103

Hormone

A substance that is made and released in one part of the body and that has an effect on another part of the body (a chemical messenger).

104

Host

Organism that provides food for a parasite.

105

Hybrid

An organism that is the result of breeding together two different species. A hybrid has characteristics from each species.

106

Hydrothermal Vent

Area on the seabed where hot gases and water are forced up from below, by being heated by magma below the sea floor.

107

Hypothalamus

Part of the brain that controls body temperature.

108

Illegal

Against the law, often punishable by a fine or imprisonment.

109

Impulse

Electrical signal transmitted along a neurone.

110

Indicator Species

Species that is particularly sensitive to or tolerant of pollution, so that its presence or absence can be used as a measure of the pollution.

111

Infectious Disease

Illness that is caused by a microorganism and can be caught from an infected person.

112

Inherited Variation

Variation caused by genes.

113

Inhibition

The feeling that you can't or shouldn't do something.

114

Insulin

Hormone released by endocrine glands in the pancreas, which decreases the blood glucose concentration by causing cells, especially those in the liver, to turn glycogen into glucose.

115

Interbreed

Reproduce with other members of the same group.

116

Interdependent

Depending on each other.

117

Internal Environment

The conditions inside your body.

118

Internal Fertilisation

When fertilisation happens inside the body of an animal.

119

Invertebrate

Animal with no backbone.

120

Key

Diagram containing a set of questions or statements that can be used to work out the name of an organism.

121

Kidney

An organ that is important in removing extra water and salts from the blood, by producig urine.

122

Kingdom

The largest division in the classification of organisms.

123

Kingdom Animalia

A large group of complex organisms that have nervous systems.

124

Kingdom Fungi

A large group of organisms that cannot make their own food. They reproduce using spores (rather than seeds) and live attached to their food source. They include moulds, yeast, mushrooms and toadstools.

125

Kingdom Plantae

A large group of organisms that usually have cells containing chloroplasts and can make their own food, using photosynthesis.

126

Kingdom Prokaryotae

A large group of organisms that consist of one cell, which does not have a nucleus. Bacteria are an example.

127

Kingdom Protoctista

A large group of organisms that do not fit into any of the other four kingdoms. Algae are an example.

128

Legal

Allowed by law.

129

Legumes

Plant of the pea family, including peas and beans.

130

Lichen

Mutualistic relationship between a fungus and an alga; different species of lichen are affected differently by air pollution, so they can be used as pollution indicators.

131

Malaria

A dangerous disease caused by a protist that caused serious fever, headaches and vomiting and can lead to death.

132

Mammals

Vertebrates that have fur, lungs and produce milk on which to feed their young.

133

Motor Neurone

Neurone that carries impulses to effectors.

134

MRSA

Methicillin-resistant Staphylococcus aureus, a strain of bacterium that is resistant to many kinds of antibiotics.

135

Multicellular

Made of more than one cell.

136

Mutation

A change in the DNA of a gene.

137

Mutualism

A relationship between organisms where both benefit.

138

Myelin Sheath

Fatty covering around the axons of many neurones. It speeds up the transmission of impulses along their length and helps to insulate them from one another.

139

Narcotic

A drug that makes you feel sleepy.

140

Natural Selection

A process in which the organisms that are best suited to the conditions in their habitats are more likely to survive.

141

Negative Feedback

A control mechanism that reacts to a change in a condition (such as temperature) by trying to bring the condition back to a normal level.

142

Negative Tropism

Tropism in which the response is away from the stimulus.

143

Nerve

Bundle of neurones.

144

Nerve Cell

Another term for neurone.

145

Nervous System

An organ system that includes the brain and nerves, which carries information around an organism.

146

Neurone

A cell that transmits electrical impulses in the nervous system.

147

Neurotransmission

Impulses passing from neurone to neurone.

148

Neurotransmitter

Substance that defuses across the gap between two neurones at a synapse, and triggers an impulse to be generated in the neurone on the other side of the synapse.

149

Nicotine

Stimulant in tobacco smoke which is addictive and makes it difficult to give up smoking.

150

Nitrifying Bacteria

Bacteria that makes more complex nitrogen compounds from simpler ones, such as nitrates from nitrites, or nitrites from ammonia.

151

Nitrogen Cycle

A sequence of processes by which nitrogen moves from the atmosphere through living and dead organisms, into the soil and back to the atmosphere.

152

Nitrogen-fixing Bacteria

Bacteria that can take nitrogen from the atmosphere and convert it to more complex nitrogen compounds, such as ammonia.

153

Normal Distribution Curve

A graph of variation in a characteristic from a population with a bell-shaped curve that shows most values in the middle of the range and a few extreme values.

154

Nucleus

The central part of an atom containing protons and neutrons. The control centre of a cell (plural: nuclei).

155

Osmoregulation

Controlling the amount of water in the body.

156

Oviparous

Offspring develop in eggs, as in birds.

157

Ovum

Female Gamete in plants and animals (plural: ova).

158

Painkiller

Substance that blocks the transmission of pain responses via neurones to the brain.

159

Pancreas

Organ in the body that produces some digestive enzymes as well as insulin and glucogen.

160

Parasite

Organism that lives on or in a host organism and takes food from it while it is alive.

161

Parasitism

A feeding relationship where one organism benefits and the other is harmed.

162

Pathogen

Microorganism that causes disease.

163

Pedigree Analysis

When doctors study family pedigree charts to assess the probability that a couple may have past on a genetic disorder to their child.

164

Phenotype

Characteristics that a certain set of alleles cause.

165

Photosynthesis

A set of chemical reactions in plants that allow them to produce their own food (glucose) losing water and carbon dioxide and releasing oxygen as a waste product. The process is powered by light from the sun.

166

Phototropism

Tropism in response to light.

167

Physical Barrier

A structure that stops something from entering a certain area. For example, the body has physical barriers like the skin, which stop microbes from getting inside the body.

168

Plant Growth Substance

A substance released by a part of a plant that has an effect on the cells of that part of another part of the plant, usually causing the cells to grow or develop in a different manner. Another term for this is plant hormone.

169

Poikilotherm

An animal whose body temperature varies with the temperature of the environment around it.

170

Pollen Grains

The male gamete in plants.

171

Pollutant

A substance that harms living organisms when released into the environment, often waste products of human activity.

172

Population Growth

Increase in population size over time

173

Positive Gravitropism

Tropism in which the response is towards the stimulus.

174

Predator

Animal that kills other animals to eat.

175

Prey

An organism that is hunted and killed by a predator.

176

Primary Consumer

An animal that eats producers (i.e. a herbivore).

177

Probability

The likelihood of something happening, often shown as a percentage chance. For example, there is a 50% chance it will rain tomorrow.

178

Producer

Organism that makes its own food, such as a plant using photosynthesis.

179

Protoctists

Simple organisms belonging to the kingdom Protoctista. Most protoctists are unicellular, although some (such as seaweeds) are multicellular. They have complex cells with a nucleus.

180

Protozoan

Type of one-celled protoctist that requires a source of food (i.e. it cannot photosynthesise as some other protoctists can).

181

Punnett Square

Diagram used to predict the different characteristics that will be present in the offspring of two organisms with known combinations of alleles. You can use the square to work out the probability than offspring will inherit a certain feature.

182

Pyramid of Biomass

Diagram showing the biomass in each trophic level of a food chain.

183

Reaction Time

How long it takes to respond to a stimulus.

184

Receptor Cell

Cell that receives a stimulus and converts it into an electrical impulse to be sent to the brain and/or spinal cord.

185

Recessive Allele

Version of a gene (allele) that will only have an effect if the other allele is also recessive.

186

Reflex

Response to a stimulus that does not require processing by the brain. The response is automatic.

187

Reflex Arc

Connection of a sensory neurone to a motor neurone (often via a relay neurone) that allows reflex actions to occur.

188

Relay Neurones

A short type of neurone, found in the spinal cord and brain, that link with sensory, motor and other relay neurones.

189

Reptiles

Vertebrates that have lungs, dry and scaly skin, and lay leathery-shelled eggs

190

Resistant

An organism that has evolved so it is not affected by substances that would usually kill it. In the case of bacteria, no longer killed by antibiotics; in the case of rats, no longer killed by warfarin poison. Organisms may vary in the range if their resistance, so that although some organisms may be killed, others may be made very ill but recover, while a few may be unaffected.

191

Respiration

Process that takes in oxygen and releases carbon dioxide, which living organisms use to release energy from food for all their activities.

192

Response

Action that occurs due to a stimulus.

193

Ring Species

A ring of populations, in which neighbouring populations that can interbreed but the populations at the two ends of the chain cannot (despite the fact that they may both live in the same area).

194

Root Nodule

Small structure that legume plants make on their roots for nitrogen-fixing bacteria to live in.

195

Rooting Powder

Powder that contains hormones called auxins that help plant cuttings to grow roots quickly.

196

Saprophytic Feeding

Getting food by digesting the tissues of other organisms outside the body and absorbing the digested food.

197

Sebaceous Glands

Glands at the base of skin hairs that release oil into the skin surface, keeping the skin lubricated and healthy.

198

Secondary Consumer

An animal that eats primary consumers.

199

Selective Weedkiller

Weedkiller that contains artificial plant hormones and will kill only certain types of plants. Most selective weedkillers kill plants with broad leaves and not those with narrow leaves.

200

Sense Organ

Organ that contains receptor cells.

201

Sensory Neurone

Neurone that carries pulses from receptors.

202

Sex Cells

Another term for gamete.

203

Sickle Cell Disease

A genetic disorder caused by inheriting two copies of a recessive allele. It causes tiredness, shortness of breath and periods of extreme pain in the joints.

204

Sludgeworm

Aquatic species that is an indicator of polluted water.

205

Speciation

Formation of new species, such as when populations of a species are separated geographically and evolve until they are no longer capable of interbreeding.

206

Species

Each different type of organism is called a species. The members of a species can reproduce with each other to produce offspring which will also be able to reproduce.

207

Sperm Cells

The male gametes in animals.

208

Spinal Cord

Large bundle of nerves, leading from the brain and down the back.

209

Stable

Something that stays the same, without changing.

210

Stimulant

Substance that increases the speed of transmission of nerve impulses across synapses.

211

Stimulus

Change in an environmental factor that is detected by receptors (plural: stimuli).

212

Stonefly Larva

Aquatic species that is an indicator of clean water.

213

Subcutaneous Fat

Layer of fat under the skin.

214

Survival of the fittest

Natural selection.

215

Swear Gland

A gland found in the skin that produces sweat.

216

Synapse

Point at which two neurones meet. There is a tiny gap between neurones at a synapse, which cannot transmit an electrical impulse.

217

Tar

Sticky black substance in tobacco smoke that contains carcinogens.

218

Target Organ

An organ on which a hormone has an effect

219

Thermoregulation

The control of temperature inside the body by mechanisms in the body.

220

Transplant

Taking an organ from one person and putting it into the body of another (often to save the life of that other person).

221

Trophic Level

One level of the good chain, such as producer, herbivore or carnivore.

222

Tropism

A response to a stimulus in which an organism grows towards or away from the stimulus.

223

Type 1 Diabetes

Type of diabetes in which the pancreas does not produce insulin.

224

Type 2 Diabetes

Type of diabetes in which cells, especially those in the liver, do not respond to insulin.

225

Unicellular

Made of one cell.

226

Urea

A nitrogen-rich substance in urine.

227

Urine

Fluid produced by the kidneys, which contains waste material from the body, water and salts.

228

Variation

Differences between characteristics in different organisms.

229

Vasoconstriction

Narrowing of the blood vessels (capillaries).

230

Vasodilation

Widening of the blood vessels (capillaries).

231

Vector

Organism that transfers a pathogen from one person to another, such as Anopheles mosquito which spreads the protozoan that causes malaria when it bites a human.

232

Vertebra

Small bone in the backbone of a vertebrate (plural: vertebrae).

233

Vertebrate

Animal with a backbone.

234

Virus

A particle that can infect cells and cause the cells to make copies of the virus, such as the influenza virus.

235

Viviparous

Mother gives birth to live young, as in mammals.