Biology

Question 1

Multicellular Organism

Answer 1

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

Question 2

Homeostasis

Answer 2

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

Question 3

Stimulus response module

Answer 3

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

Question 4

Negative feedback

Answer 4

a response that reduces the original stimulus

Question 5

Glucose

Answer 5

a simple carbohydrate and the simplest form of sugar

Question 6

Pancreas

Answer 6

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

Question 7

Insulin

Answer 7

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

Question 8

Glycogen

Answer 8

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

Question 9

Positive feedback

Answer 9

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

Question 10

Oxytocin

Answer 10

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

Question 11

Nervous system

Answer 11

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.

Question 12

Endocrine system

Answer 12

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

Question 13

Signalling molecules

Answer 13

a chemical involved in transmitting information between cells

Question 14

Central nervous system

Answer 14

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

Question 15

Peripheral nervous system

Answer 15

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.

Question 16

Sensory neurons

Answer 16

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

Question 17

Motor neurons

Answer 17

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

Question 18

Neurotransmitters

Answer 18

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

Question 19

Endocrine glands

Answer 19

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

Question 20

Hormones

Answer 20

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

Question 21

Thermoregulation

Answer 21

the control of body temperature

Question 22

Thermostat

Answer 22

a device that establishes and maintains a desired temperature automatically

Question 23

Central nervous system

Answer 23

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

Question 24

Peripheral Nervous system

Answer 24

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.

Question 25

Neurons

Answer 25

Nerve cells

Question 26

Nerves

Answer 26

A bundle of neurons

Question 27

Sensory neurons

Answer 27

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

Question 28

Interneurons

Answer 28

a nerve cell that carries nervous impulses through the central nervous system. They provide the link between sensory neurons and motor neurons.

Question 29

Motor neurons

Answer 29

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

Question 30

Nucleus

Answer 30

central part of an atom, made up of protons and neutrons; roundish structure inside a cell that acts as the control centre for the cell. Plural = nuclei.

Question 31

Organelles

Answer 31

small structure in a cell with a special function

Question 32

Cytosol

Answer 32

the fluid found inside cells

Question 33

Cell membrane

Answer 33

structure that encloses the contents of a cell and allows the movement of some materials in and out

Question 34

Cell body

Answer 34

contains the nucleus of a neuron, also called grey matter

Question 35

Dendrites

Answer 35

structure that relays information towards the cell body of a neuron

Question 36

Axon

Answer 36

an appendage of the neuron that nervous impulses travel along to the next neuron or to an effector organ (muscle or gland)

Question 37

Myelin

Answer 37

a fatty, white substance that encases the axons (connecting branches) of the neurons in the nervous system

Question 38

Synapse

Answer 38

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

Question 39

Vesicles

Answer 39

a small cavity, usually filled with fluid

Question 40

Neurotransmitters

Answer 40

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

Question 41

Effector

Answer 41

an organ that responds to a stimulus

Question 42

Reflex arc

Answer 42

a nervous pathway involving a small number of neurons. A reflex occurs when nervous impulses travel from the receptor to the spinal cord and then to the effector organ.

Question 43

Sense organs

Answer 43

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

Question 44

Stimuli

Answer 44

changes in the environment that can be detected and responded to

Question 45

Thermoreceptors

Answer 45

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

Question 46

Mechanoreceptors

Answer 46

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

Question 47

Chemoreceptors

Answer 47

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

Question 48

Photoreceptors

Answer 48

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

Question 49

Pain receptors

Answer 49

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

Question 50

Hot thermoreceptors

Answer 50

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

Question 51

Cold thermoreceptors

Answer 51

a type of receptor in your skin that can detect a decrease in skin temperature below 35.8 °C

Question 52

Olfactory nerve

Answer 52

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

Question 53

Pupil

Answer 53

a hole through which light enters the eye

Question 54

Iris

Answer 54

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

Question 55

Reflex action

Answer 55

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