B1-5, 7 Definitions

Question 1

Movement

Answer 1

An action by an organism or part of an organism causing a change of position or place

Question 2

Respiration

Answer 2

The chemical reactions in cells that break down nutrient molecules and release energy for metabolism

Question 3

Sensitivity

Answer 3

The ability to detect or sense stimuli in the internal or external environment and to make appropriate responses

Question 4

Growth

Answer 4

A permanent increase in size and dry mass by an increase in cell number or cell size or both

Question 5

Reproduction

Answer 5

Processes that make more of the same kind of organism

Question 6

Excretion

Answer 6

Removal from organisms of the waste products of metabolism (chemical reactions in cells including respiration), toxic materials, and substances in excess in requirements

Question 7

Nutrition

Answer 7

Taking in of materials for energy, growth and development; plants need light, carbon dioxide, water and ions; animals need organic compounds and ions and usually need water

Question 8

Species

Answer 8

A group of organisms that can reproduce to produce fertile offspring

Question 9

Binomial system

Answer 9

An internationally agreed system in which the scientific name of an organism is made up of two parts showing the genus and species

Question 10

What can be used as a more accurate means of classification?

Answer 10

The sequences of bases in DNA and of amino acids in proteins. This is because the sequences are specific in different organisms.

Question 11

Features in the cells of all living organisms

Answer 11

1. Cytoplasm
2. Cell membrane
3. DNA, a chemical that makes up their genetic material
4. Ribosomes, which make proteins inside the cell
5. Enzymes that help the cell to carry out anaerobic respiration

Question 12

Tissue

Answer 12

A group of cells with similar structures, working together to perform a shared function

Question 13

Organ

Answer 13

A structure made up of a group of tissues, working together to perform specific functions

Question 14

Organ system

Answer 14

A group of organs with related functions, working together to perform body functions

Question 15

Diffusion

Answer 15

The net movement of particles from a region of their higher [ ] to a region of their lower [ ] down a concentration gradient, as a result of their random movement, until an equilibrium is reached

Question 16

Osmosis

Answer 16

The net movement of water molecules from a region of high WP (dilute solution) to a region of lower WP (concentrated solution), through a partially permeable membrane

Question 17

Active transport

Answer 17

The movement of particles through a cell membrane from a region of lower [ ] to a region of higher [ ] using energy from respiration

Question 18

Catalyst

Answer 18

A substance that increases the rate of a chemical reaction and is not changed by the reaction

Question 19

Enzymes

Answer 19

Proteins that function as biological catalysts

Question 20

Balanced diet

Answer 20

A diet which contains all seven types of nutrient in the correct amounts and proportions

Question 21

Ingestion

Answer 21

The taking of substances, eg. food and drink, into the body through the mouth

Question 22

Mechanical digestion

Answer 22

The breakdown of food into smaller pieces without chemical change to the food molecules

Question 23

Chemical digestion

Answer 23

The breakdown of large, insoluble molecules into small, soluble molecules

Question 24

Absorption

Answer 24

The movement of small food molecules and ions through the wall of the intestine into the blood

Question 25

Assimilation

Answer 25

The movement of digested food molecules into the cells of the body where they are used, becoming part of the cells

Question 26

Egestion

Answer 26

The passing out of food that has not been digested or absorbed, as faeces, through the anus