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Flashcards in Biology Deck (132):
1

Multicellular organism

Multicellular organism: an organism that is composed of many cells. Most plants and animals are multicellular.

2

Homeostasis


Homeostasis: the maintenance of a relatively constant internal physiological environment of the body or part of the body (e.g. blood glucose level, pH, body temperature) in varying external conditions

3

Stimulus response model


Stimulus–response model: a system in which any changes or variations (stimuli) in the internal environment are detected (by receptors); if a response is required, this is communicated to effectors to bring about some type of change or correction so the conditions can be brought back to normal

4

Negative feedback


Negative feedback: a response that reduces the original stimulus

5

Glucose

Glucose: a simple carbohydrate and the simplest form of sugar

6

Pancreas


Pancreas: a large gland in the body that produces and secretes the hormone insulin and an important digestive fluid containing enzymes

7

Insulin

Insulin: hormone that removes glucose from the blood and stores it as glycogen in the liver and muscles

8

Glycogen

Glycogen: the main storage carbohydrate in animals, converted from glucose by the liver and stored in the liver and muscle tissue

9

Positive feedback


Positive feedback: a reaction in which the response is in the same direction as the stimulus—for example, during childbirth the onset of contractions activates the release of the hormone oxytocin, which stimulates further contractions

10

Oxytocin


Oxytocin: hormone secreted from the pituitary gland that assists in the formation of bonds between mothers and their babies, and perhaps between people in close relationships

11

Nervous system


Nervous system: the system of nerves and nerve centres in an animal in which messages are sent as an electrical and then a chemical impulse. It comprises the central nervous system and the peripheral nervous system.

12

Endocrine system


Endocrine system: the body system of glands that produce and secrete hormones into the bloodstream in order to regulate processes in various organs

13

Signalling molecules

Signalling molecules: a chemical involved in transmitting information between cells

14

Central nervous system


Central nervous system: the part of the nervous system composed of the brain and spinal cord

15

Peripheral nervous system
PNS


Peripheral nervous system (PNS): made up of sensory and motor neurons. It connects the central nervous system to the rest of the body, and detects and responds to change.

16

Sensory neurons

Sensory neurons: a nerve cell in the sense organs. It detects change in the environment and sends a message to the central nervous system.

17

Motor neurons


Motor neurons: the nerve cell that causes an organ, such as a muscle or gland, to respond to a stimulus

18

Neurotransmitters


Neurotransmitters: chemical released from the axon terminals into the synapse between your nerve cells (neurons) during a nerve impulse

19

Endocrine glands


Endocrine glands: organs that produce hormones. Endocrine glands release their hormones into the bloodstream for transport to target organs.

20

Hormones


Hormones: chemical substances produced by glands and circulated in the blood. Hormones have specific effects in the body.

21

Thermoregulation


Thermoregulation: the control of body temperature

22

Thermostat


Thermostat: a device that establishes and maintains a desired temperature automatically

23

Sense organs

Sense organs: a specialised structure that detects stimuli (such as light, sound, touch, taste and smell) in your environment

24

Stimuli

Stimuli: changes in the environment that can be detected and responded

25

Thermoreceptors


Thermoreceptors: special cells located in your skin, part of your brain and body core that are sensitive to temperature

26

Mechanoreceptors


Mechanoreceptors: special cells within the skin, inner ear and skeletal muscles that are sensitive to touch, pressure and motion, enabling you to balance, hear and sense pressure and movement

27

Chemoreceptors

Chemoreceptors: special cells within a sense organ (especially the nose and tastebuds) that are sensitive to particular chemicals, giving you the sensations of smell and taste

28

Photoreceptors

a receptor cell located in your eye that is stimulated by light, converting it to electrical energy that is sent to the brain, giving you the sensation of light

29

Pain receptor

Pain receptors: special cells located throughout the body (except the brain) that send nerve signals to the brain and spinal cord in the presence of damaged or potentially damaged cells, resulting in the sensation of pain

30

Hot thermoreceptors

Hot thermoreceptors: a type of receptor in your skin that can detect an increase in skin temperature above 37.5°C (normal body temperature

31

Cold thermoreceptors

Cold thermoreceptors: a type of receptor in your skin that can detect a decrease in skin temperature below 35.8

32

Olfactory nerve

Olfactory nerve: nerve that sends signals to the brain from the chemoreceptors in the nose

33

Pupil

Pupil: a hole through which light enters the eye

34

Iris

coloured part of the eye that opens and closes the pupil to control the amount of light that enters the eye

35

Reflex action

Reflex action: a quick response to a stimulus. Reflex actions do not involve thought.

36

Cornea

Cornea: the curved, clear outer covering of your eye

37

Lens

Lens: a transparent curved object that bends light towards or away from a point called the focus. The eye has a jelly-like lens

38

Retina

Retina: curved surface at the back of the eye. It is lined with sight receptors

39

Short-sightedness

Short-sightedness: the condition of not being able to see clearly things that are far away

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Long-sightedness

Long-sightedness: the condition of not being able to see clearly things that are close

41

Optic nerve

Optic nerve: large nerve that sends signals to the brain from the sight receptors in the retina

42

Rods

Rods: sensory receptors in the retina that respond to low levels of light and allow you to see in black and white in dim light

43

Cones

Cones: sensory receptors in the retina that respond to red, green or blue light. Cones are mainly in the central part of the retina.

44

Colour blindness

Colour blindness: an inherited condition, more common in males, in which a deficiency of one or more of the different types of cones may mean that you find it difficult to see a particular colour or combinations of colours

45

Ear canal

Ear canal: the tube that leads from the outside of the ear to the eardrum

46

Eardrum

Eardrum: a thin piece of stretched skin inside the ear that vibrates when sound waves reach it

47

Ossicles

Ossicles: a set of three tiny bones that send vibrations from the eardrum to the inner ear. They also make the vibrations larger

48

Middle ear

Middle ear: the section of the ear between your eardrum and the inner ear, containing the ossicles

49

Cochlea

Cochlea: the snail-shaped part of the inner ear. It is lined with tiny hairs that are vibrated by sound and stimulate the hearing receptors.

50

Tongue

Tongue: the sense organ responsible for taste

51

Tastebuds

Tastebuds: nerve endings located in your tongue that contain receptors sensitive to sweet, salty, bitter, sour and savoury chemicals, allowing you to experience taste

52

Papilla

Papilla: bumps on your tongue that are thought to contain tastebuds

53

Dentrities

structure that relays information towards the cell body of a neuron

54

Cognition

another name for thinking or mental activity

55

Emotions

feelings, such as happiness, sadness and anger, that are interpreted by the brain

56

Regulating

the process by which the brain detects and responds to the body’s internal and external environments

57

Hindbrain

continuation of the spinal cord

58

Pons

part of the brain involved in regulating sleep, arousal and breathing, and coordinating some muscle movements

59

Medulla oblagona

: a part of the brain developed from the posterior portion of the hindbrain and continuing with the spinal cord; see also brain stem

60

Reticular formation

network of neurons that opens and closes to increase or decrease the amount of information that flows into and out of the brain

61

Forebrain

consists of the cerebrum, cerebral cortex, thalamus and hypothalamus

62

Cerebral cortex

the outer, deeply folded surface of the cerebrum

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Thalamus

part of the brain through which all sensory information from the outside (except smell) passes before going to other parts of the brain for further processing

64

Hypothalamus

monitors internal systems and controls the release of hormones to maintain the normal body state (homeostasis)

65

Brain stem

the part of the brain connected to the spinal cord, responsible for breathing, heartbeat and digestion. Sometimes called the medulla.

66

Cerebellum

the part of the brain that controls balance and muscle action

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Cerebrum

the largest part of the brain (about 90 per cent of total brain volume), responsible for higher order thinking, controlling speech, conscious thought and voluntary actions. It is made up of the frontal, temporal, parietal and occipital lobes.

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Higher-order thinking

Higher-order thinking: involves problem solving and decision making

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Cerebral hemispheres

the left and right halves of the brain

70

Corpus calloseum

a bridge of nerve fibres through which the two cerebral hemispheres communicate

71

Synaethesia

condition in which a sensation is produced in one physical sense when a stimulus is applied to another; affected people may associate letters with a flavour, numbers with a gender or sounds with colour

72

Functional magnetic resonance imaging

fMRI): a type of specialised MRI scan used to measure the change in blood flow related to neural activity in the brain or spinal cord

73

Analogies

Analogies: a similarity between two or more things on which a comparison may be based

74

Hormones

chemical substances produced by glands and circulated in the blood. Hormones have specific effects in the body.

75

Endocrine glands

Endocrine glands: organs that produce hormones. Endocrine glands release their hormones into the bloodstream for transport to target organs.

76

Target cells

cells in the body that respond to a particular hormone

77

Pituarty gland

a small gland at the base of the brain that releases hormones

78

Pineal gland

gland that produces the hormone melatonin, which can make you feel drowsy

79

Thermoregulation

the control of body temperature

80

Insulin

hormone that removes glucose from the blood and stores it as glycogen in the liver and muscles

81

Pancreas.


Pancreas: a large gland in the body that produces and secretes the hormone insulin and an important digestive fluid containing enzymes

82

Glucose


Glucose: a simple carbohydrate and the simplest form of sugar

83

Glycogen

the main storage carbohydrate in animals, converted from glucose by the liver and stored in the liver and muscle tissue

84

Glucagon

hormone, produced by the pancreas, that increases blood glucose levels

85

Nervous system

the system of nerves and nerve centres in an animal in which messages are sent as an electrical and then a chemical impulse. It comprises the central nervous system and the peripheral nervous system.

86

Central nervous system

the part of the nervous system composed of the brain and spinal cord

87

Peripheral nervous system

made up of sensory and motor neurons. It connects the central nervous system to the rest of the body, and detects and responds to change.

88

Electrical impulses

nerve signals that pass rapidly from the receptors and along the peripheral nervous system to the central nervous system

89

Neurotransmitters

chemical released from the axon terminals into the synapse between your nerve cells (neurons) during a nerve impulse

90

Synapses

the gap between adjoining neurons across which electrical nervous impulses are sent

91

Endocrine system

the body system of glands that produce and secrete hormones into the bloodstream in order to regulate processes in various organs

92

Endocrine glands

organs that produce hormones. Endocrine glands release their hormones into the bloodstream for transport to target organs.

93

Hormones

chemical substances produced by glands and circulated in the blood. Hormones have specific effects in the body.

94

Digestive system


Digestive: a complex series of organs and glands that processes food in order to supply your body with the nutrients it needs to function effective

95

Respiratory

concerning the airways or breathing

96

Circulatory

the body system that circulates oxygen in blood to all the cells of the body. The circulatory system consists of the heart, blood vessels and blood.

97

Excretory

the body system that removes waste substances from the body

98

Respiratory system

the body system involving the lungs and associated structures, which take in air and supply the blood with oxygen to deliver to the body's cells so they can carry out their essential functions; it also performs gas exchange to remove the waste gas carbon dioxide

99

Trachea

narrow tube from the mouth to the lungs through which air moves

100

Lungs

Lungs: the organ for breathing air. Gas exchange occurs in the lungs.

101

Bronchi

the narrow tubes through which air passes from the trachea to the smaller bronchioles and alveoli in the respiratory system. Singular = bronchus.

102

Bronchioles

small branching tubes in the lungs leading from the two larger bronchi to the alveoli

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Alveoli

tiny air sacs in the lungs at the ends of the narrowest tubes. Oxygen moves from alveoli into the surrounding blood vessels, in exchange for carbon dioxide.

104

Capillaries

minute tubes carrying blood to body cells. Every cell of the body is supplied with blood through capillaries.

105

Circulatory system

the body system that circulates oxygen in blood to all the cells of the body. The circulatory system consists of the heart, blood vessels and blood.

106

Digestive system

a complex series of organs and glands that processes food in order to supply your body with the nutrients it needs to function effectively

107

Enzymes

special chemicals that speed up reactions but are themselves not used up in the reaction

108

Endocrine system

the body system of glands that produce and secrete hormones into the bloodstream in order to regulate processes in various organs

109

Norepinephrine

also called noradrenaline; common neurotransmitter involved in arousal states

110

Oxygen


Oxygen: a gas in the air (and water) that animals need to breathe; made up of particles with two oxygen atoms. Plants produce oxygen as part of photosynthesis.

111

Cellular respiration

the chemical reaction involving oxygen that moves the energy in glucose into the compound ATP. The body is able to use the energy contained in ATP.

112

Glucose


Glucose: a simple carbohydrate and the simplest form of sugar

113

Trachea

narrow tube from the mouth to the lungs through which air moves

114

Bronchi

the narrow tubes through which air passes from the trachea to the smaller bronchioles and alveoli in the respiratory system. Singular = bronchus.

115

Capillaries

minute tubes carrying blood to body cells. Every cell of the body is supplied with blood through capillaries.

116

Veins

blood vessels that carry blood back to the heart. They have valves and thinner walls than arteries.

117

Arteries

hollow tubes (vessels) with thick walls carrying blood pumped from the heart to other body parts

118

Red blood cells

living cells in the blood that transport oxygen to all other living cells in the body. Oxygen is carried by the red pigment haemoglobin.

119

Erythrocytes

Red blood cells

120

Haemoglobin

the red pigment in red blood cells that carries oxygen

121

Pulmonary vein

the vessel through which oxygenated blood travels from your lungs to the heart

122

Left atrium

upper left section of the heart where oxygenated blood from the lungs enters the heart

123

Left ventricle

lower left section of the heart, which pumps oxygenated blood to all parts of the body

124

Heart


Heart: a muscular organ that pumps blood through the circulatory system so that oxygen and nutrients can be transported to the body's cells and wastes can be transported away

125

Aorta


Aorta: a large artery through which oxygenated blood is pumped at high pressure from the left ventricle of your heart to your body

126

Arterioles

vessels that transport oxygenated blood from the arteries to the capillaries

127

Deoxygenated blood

blood from which some oxygen has been removed

128

Vena cava

large vein leading into the top right chamber of the heart

129

Right atrium

upper right section of the heart where deoxygenated blood from the body enters

130

Right ventricle

lower right section of the heart, which pumps deoxygenated blood to the lungs

131

Pulmonary artery

the vessel through which deoxygenated blood, carrying wastes from respiration, travels from the heart to the lungs

132

Digestion

G Digestion: breakdown of food into a form that can be used by an animal. It includes both mechanical digestion and chemical digestion