Topic 1 Cell Biology - Definitions

Question 1

Active transport

Answer 1

​The movement of substances from a more dilute solution to a more concentrated solution (against a concentration gradient) with the use of energy from respiration.

Question 2

Adult stem cell

Answer 2

​A type of stem cell that can form many types of cells.

Question 3

Agar jelly

Answer 3

​A substance placed in petri dishes which is used to culture microorganisms on.

Question 4

Cell differentiation

Answer 4

​The process where a cell becomes specialised to its function.

Question 5

Cell membrane

Answer 5

​A partially permeable barrier that surrounds the cell.

Question 6

Cell wall

Answer 6

​An outer layer made of cellulose that strengthens plant cells.

Question 7

Chloroplast

Answer 7

​An organelle which is the site of photosynthesis.

Question 8

Chromosomes

Answer 8

​DNA structures that are found in the nucleus which are made up of genes.

Question 9

Concentration gradient

Answer 9

​The difference in concentration between two areas.

Question 10

Diffusion

Answer 10

​The spreading out of the particles of any substance in solution, or particles of a gas, resulting in a net movement from an area of higher concentration to an area of lower concentration.✢

Question 11

Embryonic stem cell

Answer 11

​A type of stem cell that can differentiate into most types of human cells.

Question 12

Eukaryotic cell

Answer 12

​A type of cell found in plants and animals that contains a nucleus.

Question 13

Magnification

Answer 13

​How much bigger an image appears compared to the original object.

Question 14

Mitochondria

Answer 14

​ An organelle which is the site of respiration.

Question 15

Mitosis

Answer 15

​A type of cell division which produces two genetically identical daughter cells from one parent cell.

Question 16

Nucleus

Answer 16

​An organelle found in most eukaryotic cells that contains the genetic material of the cell and controls the activities of the cell.

Question 17

Organelle

Answer 17

​A specialised structure found inside a cell.

Question 18

Osmosis

Answer 18

​The diffusion of water from a dilute solution to a concentrated solution through a partially permeable membrane.

Question 19

Plasmid

Answer 19

​Loops of DNA found in the cytoplasm of prokaryotic cells.

Question 20

Prokaryotic cell

Answer 20

​A type of cell found in bacteria that does not contain a nucleus.

Question 21

Resolution

Answer 21

​The ability to distinguish two different points in a specimen.

Question 22

Specialised cells

Answer 22

​Cells that are adapted to perform a specific function​.

Question 23

Stem cell

Answer 23

​An undifferentiated cell that can divide to produce many specialised cells of the same type.

Question 24

Surface area to volume ratio (SA

Answer 24

​The size of the object compared with the amount of area where it contacts its environment.

Question 25

Surface area

Answer 25

​The amount of contact an object has with its environment.

Question 26

The cell cycle

Answer 26

​A series of stages preparing the cell for division.

Question 27

Therapeutic cloning

Answer 27

​Producing an embryo that has the same genes as a patient.

Question 28

Vacuole

Answer 28

​An organelle that stores cell sap.