1(b) Variety of Living Organisms

Question 1

Plants

Students should know

Answer 1

Multicellular organism; thir cells contain chloroplasts and are ableto carry out photosynthesis; their ells have cellulose cell walls; they store carbohydrates as starch or sucrose. Examples include flowering plants, such as a cereal (maize), and a herbaceous legume (peas or beans)

Question 2

Animals

Students should know

Answer 2

Multicellular organism; their cells do not contain chloroplasts and are not able to carry out photosyntheses; they have no cell walls; they usually have nervous co-ordination and are able to move from one place to another; they often store carbohydrates as glycogen. Examples include mammals, and insects.

Question 3

Fungi

Students should know

Answer 3

Organisms unable to carry out photosyntheses; their body is usually organised into a mycelium made from thread-like structures called hyphae, which contain many nuclei; some examples are single-celled; their cells have walls made out of chitin; they feed by extracellular secretion of digestive enzymes onto food material and absorption of the organic products; this is known as saprotrophic nutrition; they may store carbohydrate as glycogen. Examples include Mucor, which is single-celled.

Question 4

Protoctists

Students should know

Answer 4

Microscopic single-celled organism. Some have animal cell like features like Amoeba others are more like plants like Chlorella which contain chloroplasts. Plasmodium the pathogenic example for causing malaria.

Question 5

Describe the common features shown by the prokaryotic organisms such as bacteria

Students should know

Answer 5

Microscopic single-celled organism; they have a cell wall, cell membrane, cytoplasm and plasmids; they lack a nucleus but contain a circular chromosome of DNA; some bacteria can carry out photosynthesis but most feed off other living or dead organisms. Examples include Lactobacillus bulgaricus, a rod-shaped bacterium used in the production of yoghurt from milk, and Pneumococcus, a spherical bacterium that acts as the pathogen causing pneumonia.

Question 6

Understand the term pathogen and know that pathogens may include fungi, bacteria, protoctists or viruses

Students should know

Answer 6

Not living organisms. Smaller than bacteria; they are parasitic and can reproduce only inside living cells; they infect every type of living organism. They have no cellular structure but have a protein coat and contain one type of nucleic acid, either DNA or RNA. Examples include the tobacco mosaic virus that causes discolouring in tobacco plant leaves by preventing the formation of chloroplasts, the influenza virus that causes ‘flu’ and the HIV virus that causes AIDS.

Question 7

Photosythesis

Answer 7

A chemical reaction in plants that uses light energy from the sun to convert carbon dioxide and water to glucose and oxygen.

Question 8

Cytoplasm

Answer 8

The material inside a cell in which cellular structures are found. Site of many chemical reaction within the cell.

Question 9

Ribosome

Answer 9

Organelle in a cell where protein synthesis occurs.

Question 10

Protoctists

Answer 10

Microscopic, single-celled organism. Examples include Plasmodium and chlorella.

Question 11

Viruses

Answer 11

Very small, non-living particles that can only reproduce inside living cells. Possess a protein coat and genetic material only.

Question 12

Organ

Answer 12

Group of tissues with a common function

Question 13

Plasmodium

Answer 13

A pathogenic example of a protoctist that causes malaria.

Question 14

Cell wall

Answer 14

Strong, freely permeable structure around the outside of plant cells. Made of cellulose in plants and chitin in fungi.

Question 15

HIV

Answer 15

An example of a virus that causes AIDS.

Question 16

Hyphae

Answer 16

Thread-like structures, often containing many nuclei. Found in fungi.

Question 17

Fungi

Answer 17

Organism that feed by saprotrophic nutrition. Have a body made up of mycelium containing many hyphae and cell walls containing chitin. Act as decomposers.

Question 18

Mucor

Answer 18

An example of a multicellular fungus.

Question 19

Prokaryote

Answer 19

An organism that does not have a nucleus. Mostly the bacteria kingdom.

Question 20

Legume

Answer 20

A group of plants that includes peas and beans.

Question 21

Organelle

Answer 21

Structure inside a cell, e.g. chloroplast or mitochondrion.

Question 22

Chloroplasts

Answer 22

Organelle inside plant cells. Site of photosythesis reactions. Contains chlorophyll.

Question 23

Starch

Answer 23

Glucose storage molecule found in plant cells

Question 24

Yeast

Answer 24

An example of a single-celled fungus

Question 25

Chlorella

Answer 25

An example of a protoctist that has chloroplasts and similar feature to a plant cell

Question 26

Selectively permeable

Answer 26

Barrier that only allows certain molecules to cross.

Question 27

Animals

Answer 27

Multicellular organisms that cannot photosynthesise. They store carbohydrates as glycogen.

Question 28

Pathogen

Answer 28

An organism which causes disease.

Question 29

Mitochondria

Answer 29

Organelle found inside cells. Site of respiration reaction.

Question 30

Multicellular

Answer 30

Used to descrive an organism that is made up of more than one cell.

Question 31

Tissue

Answer 31

Group of similar cells with the same function.

Question 32

Cellulose

Answer 32

Carbohydrate used to make plant cell walls.

Question 33

DNA

Answer 33

Deoxyribonucleic acid. The genetic material found inside most organisms' cells.

Question 34

Nucleus

Answer 34

Organelle that controls the activities of a cell. Contains DNA.

Question 35

Bacteria

Answer 35

Single-celled organisms with no nuclei. Some can photosynthesis. Some are decomposers, decaying dead organic matter.

Question 36

Lactobacillus

Answer 36

An example of a bacterium used in yoghurt production.

Question 37

Organ system

Answer 37

Group of organs with a common function.

Question 38

Starch

Answer 38

A carbohydrate that is used to store glucose in plant cells.

Question 39

Vacuole

Answer 39

Structure inside a plant cell that is used to store minerals and sugar solution.

Question 40

Cell membrane

Answer 40

Selectively permeable barrier surrounding the cell. Made largely of lipid molecules.

Question 41

Glycogen

Answer 41

Glucose storage molecule found in animal and fungal cells.

Question 42

Flagelum

Answer 42

Long projection from a bacterial cell that allows movement.

Question 43

Plants

Answer 43

Multicellular organisms that are able to photosynthesise. Store sugar as starch and have cellulose cell walls.

Question 44

Chitin

Answer 44

Substance used to make fungal cell walls.

Question 45

Pneumococcus

Answer 45

An example of a bacterium that causes pneumonia

Question 46

Mycelium

Answer 46

The main body of a fungus. Made of many hyphae.

Question 47

Saprotrophic nutrition

Answer 47

Method of feeding in fungi where digestive enzymes are secreted onto food material and the products are absorbed.

Question 48

Eukaryote

Answer 48

An organism that has a nucleus. Plant, Animal, Protoctists and Fungi.

Question 49

Amoeba

Answer 49

An example of a protoctist that lives in water and has similar features to an animal cell.