Definitions

Question 1

Active transport

Answer 1

The active movement of substances from a low concentration to a higher concentration (up their concentration gradient) with the use of energy in the form of ATP.

Question 2

Antibody

Answer 2

A protein found in the blood that is produced by plasma cells which binds to antigens as a part of the immune response.

Question 3

Antigen

Answer 3

Marker molecules that can be detected by antibodies and trigger an immune response.

Question 4

Cell cycle

Answer 4

The series of stages preparing the cell for division consisting of interphase and mitosis.

Question 5

Co-transport

Answer 5

A method of membrane transport where two substances are both transported across a membrane at the same time either in the same direction or opposite directions.

Question 6

Cytokinesis

Answer 6

Division of the cytoplasm to produce two new cells.

Question 7

Facilitated diffusion

Answer 7

The passive movement of substances from a high concentration to a lower concentration (down their concentration gradient) through transport proteins without the
use of energy.

Question 8

Fluid-mosaic model

Answer 8

A model that describes membrane structure as a sea of mobile phospholipids studded with various proteins.

Question 9

Helper T cell

Answer 9

A type of T cell in the immune system that stimulates cytotoxic T cells, B cells and phagocytes.

Question 10

Herd immunity

Answer 10

A type of disease immunity that occurs when a large proportion of a population are vaccinated against a disease which prevents the spread of the disease to unvaccinated individuals.

Question 11

Human Immunodeficiency Virus (HIV)

Answer 11

A virus that attacks T cells in the immune system and can lead to AIDS (acquired immune deficiency syndrome).

Question 12

Lysosomes

Answer 12

Membrane-bound vesicles found in the cytoplasm that contain a hydrolytic enzyme called lysozyme.

Question 13

Mitosis

Answer 13

The part of the cell cycle in which a eukaryotic cell divides to produce two daughter cells, each with identical copies of DNA.

Question 14

Nucleus

Answer 14

An organelle found in eukaryotic cells that stores the genetic information of the cell as chromosomes and is surrounded by a membrane called the nuclear envelope.

Question 15

Osmosis

Answer 15

The passive diffusion of water molecules from a region of high water potential to a region of lower water potential (down a water potential gradient) through a selectively permeable membrane without the use of energy.

Question 16

Monoclonal antibodies

Answer 16

Identical antibodies that have been produced by an immune cell that has been cloned from a parent cell.

Question 17

Phagocytosis

Answer 17

The process where phagocytes engulf and destroy material.

Question 18

Passive immunity

Answer 18

A form of immunity provided by the introduction of antibodies to a disease into the body.

Question 19

Primary immune response

Answer 19

The response produced by the immune system when it encounters a pathogen for the first time.

Question 20

Plasmids

Answer 20

A circular loop of DNA found in the cytoplasm of bacterial cells.

Question 21

Ribosomes

Answer 21

Organelles found either free in the cytoplasm or membrane bound that are involved in the synthesis of proteins.

Question 22

Rough endoplasmic reticulum (RER)

Answer 22

A membrane-bound organelle that is involved in the synthesis and packaging of proteins.

Question 23

Secondary immune response

Answer 23

The response produced by the immune system when it recognises a pathogen that it has encountered before.

Question 24

Simple diffusion

Answer 24

The passive spreading out of substances from a high concentration to a lower concentration (down their concentration gradient) without the use of energy.

Question 25

Smooth endoplasmic reticulum (SER)

Answer 25

A membrane-bound organelle involved in lipid synthesis.

Question 26

Vaccine

Answer 26

The introduction of dead or inactive pathogens to stimulate an immune response and provide long term immunity.