Section 2: Classification and the Diversity of Life

Question 1

What are the 5 major groups of organisms?

Answer 1

They are plants, animals, fungi, protoctists, bacteria and viruses

Question 2

What are plants in terms of cells?

Answer 2

They are mutlicellular

Question 3

What do plants contain that carry out photosynthesis?

Answer 3

Chloroplasts

Question 4

What are one of the products of photosynthesis?

Answer 4

The carbohydrate cellulose

Question 5

What do all plants cells have that are made of cellulose?

Answer 5

Cell walls

Question 6

What do plants make as a result of photosynthesis?

Answer 6

Organic compounds such as starch (carbohydrate) and sucrose (sugar)

Question 7

What are animals in terms of cells?

Answer 7

They are multicellular

Question 8

How do animals gain nutrition?

Answer 8

They gain nutrition by feeding on other animals or platns

Question 9

As animals don’t have cell walls, what can they do that plants can’t do?

Answer 9

Their cells can change shape

Question 10

How do animals move?

Answer 10

They move by a nervous system

Question 11

What is the compound glycogen?

Answer 11

It is a compound found in animals cells that store carbohydrates

Question 12

What is an example of multicellular fungi?

Answer 12

Mushrooms, toadstools and moulds

Question 13

What is an example of a unicellular fungi?

Answer 13

Yeast

Question 14

How many yeast cells does yeast powder contain?

Answer 14

Millions

Question 15

Does fungi photosynthesise?

Answer 15

No

Question 16

Is the cell wall of fungi made of cellulose?

Answer 16

No

Question 17

What is the fruiting body of fungus?

Answer 17

It is the reproductive structure of the organism (like a mushroom or a toadstool)

Question 18

What is the hyphae of fungus?

Answer 18

It is the fine thread-like filaments that are under the soil

Question 19

What is a mycelium?

Answer 19

A whole network of hyphae

Question 20

How do moulds feed?

Answer 20

They feed by absorbing nutrients from dead materials

Question 21

What occurs when there is mould on food?

Answer 21

Mouldy food is due to mould spores in the air that have landed on the food and have grown into a mycelium or hyphae

Question 22

What is the cell structure of a hyphae?

Answer 22

The hyphae are not divided up into seperate cells. Instead they have cell walls surrounding the cytoplasm and the cytoplasm contains many nuclei

Question 23

How does mould digest food?

Answer 23

The mould spores land on the food > a hypha grows out from it > the hypha grows branches again and again until the mycelium covers the surface of the food > the hyphae secretes digestive enzymes onto the food - breaking it down into soluble substances > the mould absorbs it. Mould then releases more spores.

Question 24

What is saprotrophic nutrition?

Answer 24

When organisms feed on dead organic material and digestion occurs outside of the organism

Question 25

What is an extracellular enzyme?

Answer 25

The enzyme that is secreted out of mould

Question 26

What do protoctists consist of?

Answer 26

A mixed group of organisms that don't fit in plants, animals or fungi

Question 27

What are most organisms that are considered to be part of the protoctist kingdom?

Answer 27

They tend to be microscopic single-celled organisms

Question 28

What do the cells of organisms that are considered to be part of the protoctist kingdom like?

Answer 28

They are mixed; some look like animals cells and some look like plant cells

Question 29

What are the animal cell looking organisms in the protoctist kingdom called?

Answer 29

Protozoa

Question 30

What are the plant cell looking organisms in the protoctist kingdom called?

Answer 30

Algae

Question 31

What are bacteria in terms of cells?

Answer 31

They are single-celled organisms

Question 32

What is the size and structure of a bacteria cell like?

Answer 32

They are much smaller than animal, plant and protoctist cells. They are also much simpler too.

Question 33

What are the 3 basic shapes of bacteria cells?

Answer 33

Spheres, rods and spirals

Question 34

What are the internal structure of the 3 basic shapes of bacteria cells like?

Answer 34

They all have similar internal structures

Question 35

What are bacteria cells walls made of?

Answer 35

Polysaccharides and proteins (different to virus and plant cells)

Question 36

What do some bacteria cells have another layer of?

Answer 36

Some have another layer of cell wall that is called the capsule or slime layer

Question 37

Do bacteria cells have cell membranes?

Answer 37

Yes they do

Question 38

What is the middle of the bacteria cell made of?

Answer 38

Cytoplasm

Question 39

Do bacteria cells have a nucleus?

Answer 39

No, but instead have a single chromosome

Question 40

Some bacteria cells have a flagella, what is it?

Answer 40

A propeller for swimming (corkscrew motion)

Question 41

Some bacteria cells have plasmids, what is it?

Answer 41

A circular ring of DNA

Question 42

What do some bacteria cells have a form of in their cytoplasm?

Answer 42

A from of chromosome - some can photosynthesis

Question 43

How do most bacteria cells gain nutrition?

Answer 43

Most feed off other living or dead organisms. They are important decomposers

Question 44

Do all bacteria cells carry out the normal processes of life?

Answer 44

Yes they do, some even respond to stimuli - they move towards food or away from poisonous chemicals

Question 45

What are all viruses?

Answer 45

Parasites - they reproduce inside their 'host' cells

Question 46

What are viruses not made of?

Answer 46

They are not made of cells - they do not have a nucleus or cytoplasm

Question 47

What are viruses made of?

Answer 47

They are just composed of a core genetic material surrounded by a protein coat

Question 48

What do viruses have instead of DNA?

Answer 48

They have RNA instead

Question 49

Why do some viruses have a cell membrane called an 'envelope'?

Answer 49

As they stole it from the surface membrane of their host cell

Question 50

Why do some scientists believe that viruses are not alive?

Answer 50

As they do not do any of the normal 'characteristics' of living - except reproduction, which they do parasitically

Question 51

How do viruses reproduce?

Answer 51

They enter the host cell and take over the host's genetic machinery to make more virus particles. The host cells die and particles are released to infect more cells.

Question 52

How do humans not die by a virus?

Answer 52

Our body's immune system destroys the virus before we die