Section 1 - The Nature and Variety of Organisms

Question 1

Cell membrane

Answer 1

Surrounds the cell forming a boundary between the inside and outside of the cell. Selectively permeable as it controls the entry and exit of chemicals.

Question 2

Mitochondria

Answer 2

Site of aerobic respiration.

Question 3

Nucleus

Answer 3

Contains the genetic material of the cell (DNA)

Question 4

Ribosomes

Answer 4

Site of protein synthesis

Question 5

Cytoplasm

Answer 5

A jelly-like substance where most chemical reaction takes place

Question 6

Cell wall

Answer 6

A layer of non-living material that is found outside the cell membrane. Helps the cell keeps its shape and provides support.

Question 7

Vacuole

Answer 7

A large central space filled with watery liquid called cell sap. It is a store of dissolved sugars, mineral ions.

Question 8

Chloroplasts

Answer 8

Contain a green pigment called chlorophyll. Chlorophyll absorbs light energy to make food in a process called photosynthesis.

Question 9

Eukaryotic cells

Answer 9

Cells which do contain a nucleus.
ex) Plant, animal, fungi, proctoctist

Question 10

Prokaryotic cells

Answer 10

Cells which do not contain a nucleus.
ex) bacteria

Question 11

Lactobacillus bulgaricus

Answer 11

a rod-shaped bacterium used in the production of yoghurt from milk

Question 12

Pneumococcus

Answer 12

a spherical bacterium that acts as the pathogen causing pneumonia

Question 13

pathogen

Answer 13

microorganisms that cause infectious disease

Question 14

Enzyme

Answer 14

A biological catalyst that speeds up a reaction without being used up itself

Question 15

Diffusion

Answer 15

the net movement of particles from an area of higher concentration to an area of low concentration

Question 16

Osmosis

Answer 16

the net movement of water molecules across a partially permeable membrane from a region of higher water concentration to a region of lower water concentration

Question 17

Active Transport

Answer 17

the movement of particles against a concentration gradient (from an area of lower concentration to an area of higher concentration) using energy released during respiration