Topic 1: The Nature And Variety Of Living Organisms

Question 1

Amoeba

Answer 1

Protoctists that live in pond water and resemble animal cells

Question 2

Cell

Answer 2

The basic building block of all living organisms

Question 3

Cell Membrane

Answer 3

An outer, structural layer that surrounds some cells. In plant cells, it is made of cellulose. In fungi, it is made of chitin

Question 4

Chlorella

Answer 4

A protoctist that has features similar to plant cells (e.g. chloroplasts)

Question 5

Chloroplast

Answer 5

An organelle which is the site of photosynthesis

Question 6

DNA

Answer 6

A double-stranded polymer wound to form a double helix. It carries the genetic code.

Question 7

Eukaryotic cell

Answer 7

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

Question 8

Human Immunodeficiency Virus (HIV)

Answer 8

An infectious virus that weakens the immune system and can lead to AIDS (acquired immunodeficiency syndrome)

Question 9

Hyphae

Answer 9

Long filaments of a fungus that contain many nuclei

Question 10

Influenza Virus

Answer 10

An infection virus that causes influenza (the flu)

Question 11

Lactobacillus bulgaricus

Answer 11

A rod-shaped species of bacterium used to produce yoghurt from milk

Question 12

Mucor

Answer 12

A multicellular fungus that has a hyphal structure

Question 13

Mycellium

Answer 13

A collection of thread-like hyphae in a fungus

Question 14

Pathogens

Answer 14

Microorganisms that cause infectious disease

Question 15

Photosynthesis

Answer 15

An endothermic reaction in which energy is transferred from the environment to the chloroplasts by light

Question 16

Plasmids

Answer 16

Loops of DNA found in the cytoplasm of prokaryotic cells

Question 17

Plasmodium

Answer 17

Pathogenic protoctists that cause malaria

Question 18

Pneumococcus

Answer 18

A spherical, pathogenic bacterium that causes pneumonia

Question 19

Prokaryotic cell

Answer 19

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

Question 20

Protoctists

Answer 20

Microscopic single-celled organisms

Question 21

Saprotrophic nutrition

Answer 21

The mode of extracellular nutrition in which digestive enzymes are secreted onto the food outside the cell and the products of digestion are absorbed

Question 22

Tobacco Mosaic Virus (TV)

Answer 22

A widespread plant pathogen affecting many species of plants which produces a mosaic pattern on the leaves. It infects chloroplasts and limits plant growth.

Question 23

Virus

Answer 23

A non-living organism that can only reproduce inside host cells. Viruses have no cells, but possess a protein coat containing nucleic acids (DNA or RNA).

Question 24

Yeast

Answer 24

A single-celled fungus