Topic 2 - Definitions

Question 1

Active immunity

Answer 1

A form of immunity provided by the immune response of the body upon detection of a pathogen.

Question 2

Active transport

Answer 2

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

Question 3

Agglutination

Answer 3

The clamping together of cells or particles caused by antibodies which assists phagocytosis.

Question 4

Antibody

Answer 4

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

Question 5

Binary fission

Answer 5

The method of cell division used by prokaryotes involving replication of the circular DNA and plasmid followed by a cytoplasmic division.

Question 6

Cell cycle

Answer 6

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

Question 7

Cell surface membrane

Answer 7

A phospholipid bilayer studied with proteins that surround cells and separates them from their environment.

Question 8

Cell vacuole

Answer 8

A membrane bound structure found in plant cells that contains cell sap.

Question 9

Cell wall

Answer 9

A permeable layer that surrounds plants, algae and fungi cells made of polysaccharides which provides strength to the cell.

Question 10

Chloroplast

Answer 10

An organelle found in plants and algae that is the site of photosynthesis.

Question 11

Clonal expansion

Answer 11

The production of many genetically identical daughter cells through cell division of the activated B or T lymphocyte after clonal selection.

Question 12

Clonal selection

Answer 12

The process of matching the antigens on an antigen presenting cell with the antigen receptors on B and T lymphocytes.

Question 13

Co transport

Answer 13

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

Question 14

Cytokinesis

Answer 14

Division of the cytoplasm to produce two new cells.

Question 15

Facilitated diffusion

Answer 15

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 16

Flagella

Answer 16

A whiplike structure found on bacterial cells that is used for its cell movement.

Question 17

Fluid mosaic model

Answer 17

A model that describes membrane structures as a sea of mobile phospholipids studed with various proteins.

Question 18

Golgi apparatus

Answer 18

An organelle found in eukaryotic cells that is involved in the modification and packaging of proteins and lipids.

Question 19

Helper T cell

Answer 19

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

Question 20

Herd immunity

Answer 20

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 21

Human immunodeficiency virus

Answer 21

A virus that attacks T cells in the immune system and can lead to AIDS.

Question 22

Lysosomes

Answer 22

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

Question 23

Magnification

Answer 23

How much bigger an image appears compared to the original object calculated using the following formula:
Image size = actual size x magnification

Question 24

Mitochondria

Answer 24

An organelle found in eukaryotic cells that is the site of aerobic respiration.

Question 25

Mitosis

Answer 25

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

Question 26

Monoclonal antibodies

Answer 26

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

Question 27

Nucleus

Answer 27

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 28

Osmosis

Answer 28

The passive diffusion of water molecules from a region of high water potential to a region of low water potential through a selectively permeable membrane without the use of energy.

Question 29

Passive immunity

Answer 29

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

Question 30

Phagocytosis

Answer 30

The process where phagocytes engulf and destroy material.

Question 31

Plasmids

Answer 31

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

Question 32

Primary immune response

Answer 32

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

Question 33

Resolution

Answer 33

The ability to distinguish two different points in a specimen.

Question 34

Ribosomes

Answer 34

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

Question 35

Rough endoplasmic reticulum

Answer 35

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

Question 36

Secondary immune response

Answer 36

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

Question 37

Simple diffusion

Answer 37

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

Question 38

Smooth endoplasmic reticulum

Answer 38

A membrane bound organelle involved in lipid synthesis.

Question 39

Vaccine

Answer 39

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