Answer to Continuous Evaluation New Biology — a modern approach
1 Studying Biology
Part I Check your progress
1.1 What is biology?
1. Zoology
2. Cytology
3. Human biology
4. Botany
5. Genetics
6. Ecology
7. Microbiology
8. Taxonomy
1.2 Why do we study biology?
1. F
2. F
3. F
4. T
1.3 Important biological inventions and discoveries
1.4 Biological terms
1. enzyme
2. kill
3. cell
4. study
5. breakdown
6. substance
7. against
8. life
9. cell
10. remove
1.5 How do we study biology?
A. 1. Making observations
2. Making hypothesis
3. Doing experiments
4. Collecting new data
5. Revision
B. 1. Do not put the labels on the diagram itself.
2. Labels should be written horizontally.
3. The labelling lines should not intersect one another.
4. Give the diagram a suitable title and include the scale of magnification.
1.6 The characteristics of living organisms
A. 1. nutrition
2. respiration
3. excretion
4. growth
5. reproduction
6. sensitivity
7. movement
B. The motor car does not have the characteristics of growth, reproduction and sensitivity. And only combusting (but not respiration) occurs in the motor car to release energy.
C. 1. T
2. F
3. F
4. F
5. F
2 Chemicals of life
Part I Check your progress
2.1 What are organisms made of?
1. C
2. C
3. C
2.2 The functional roles of the organic substances in organisms
A. 1. (a) carbon
(b) hydrogen
(c) oxygen
2. (d) glucose
3. (e) starch
(f) glycogen
4. (g) Cellulose
5. (h) energy
6. (i) amino acids
(j) nitrogen
7. (k) genes
B. 1. F
2. T
3. F
4. T
5. F
6. F
2.3 The importance of water to life
A. 1. T
2. F
3. T
4. T
5. F
6. F
B. 1. cooling agent
2. medium of transport
3. reactant / hydrolysing agent
4. supporting agent
5. solvent
6. medium of transport
2.4 The presence of minerals in all living cells
1. B
2. C
3. D
3 The cell as the basic unit of life
Part I Check your progress
3.1 Discovery of cells
1. F
2. T
3. T
4. T
5. F
3.2 Microscope
A. 1. F
2. D
3. C
4. B
5. A
6. H
7. E
8. G
B. 1. A
2. C
3.3 Basic structure of a cell
A. 1. C
2. A
B. 1. cell membrane
2. cytoplasm
3. mitochondria
4. chloroplasts
5. cell wall
6. nucleus
7. vacuole
8. chromosomes
3.4 The similarities and differences between plant and animal cells
1. a
2. c
3. c
4. b
5. a
6. c
7. a
8. c
9. a
10. c
3.5 The cell as a basic unit of life
A. 1. B
2. C
B. 1. nucleus → cell → tissue → organ → system → organism
2. (i) E
(ii) C, D
(iii) D
(iv) A
(v) B
4 Cell activities
Part I Check your progress
4.1 Metabolism
1. b
2. a
3. b
4. b
5. c
4.2 The role of enzymes in metabolism
4.3 The nature and properties of enzymes
A. 1. (a) reusable
2. (b) protein
(c) denatured
3. (d) specific
B. 1. F
2. F
3. T
4. T
5. F
6. F
4.4 The mechanism of enzyme action
(a) C: enzyme D: product X: enzyme-substrate complex
(b) Look-and-key hypothesis
(c) Both the active site of the enzyme and the key have a specific shape which fits into a
particular substrate and lock respectively.
(d) Formation of protein / starch / growth (or any suitable answer)
4.5 Factors affecting enzyme activity
A. 1. C
2. C
3. A
B. (a) From 0−45ºC, the enzyme activity increases when the temperature increases.
From 45−60ºC, the enzyme activity decreases when the temperature increases.
The optimum temperature for enzyme activity is 45ºC
(b) The enzyme is inactive but not denatured at low temperatures. It regains its activity
when the temperature increases.
4.6 Movement of substances across the cell membrane
A. 1. C
2. B
3. A
B. 1. (i) b
(ii) a
(iii) b, c
(iv) b
(v) a
2. (a) √
(b) osmosis
(c) lower
(d) √
(e) not
(f) √
5 Diversity of organisms and classification
Part I Check your progress
5.1 The diversity of organisms
5.2 Classification
A. 1. F
2. T
B. 1. (a) taxonomy
2. (b) species
(c) common features
(d) interbreed
(e) offspring
5.3 Kingdom prokaryotae
5.4 Kingdom protoctista
5.5 Kingdom fungi
A. 1. F
2. T
3. F
4. F
5. T
B. 1. (a) prokaryotes
(b) nucleus
2. (c) saprophytic
(d) parasitic
3. (e) algae
(f) water
4. (g) hyphae
(h) spores
5.6 Kingdom plantae
1. (a) ferns
(b) spores
2. (c) rhizoids
3. (d) Gymnosperms
4. (e) mosses
(f) ferns
(g) gymnosperms
(h) flowering plants (angiosperms)
(i) dicotyledons
(j) monocotyledons
5.7 Kingdom animalia
1. birds, mammals
2. amphibians (adult), reptiles, birds, mammals
3. amphibians (tadpoles), fish
4. fish, reptile, birds (on the legs)
5. birds
6. reptiles, birds
7. mammals
8. birds
9. mammals
10. amphibians
5.8 Identifying organisms with simple keys
(a) A snail
B earthworm
C ant
D spider
E centipede
(b) Ant, spider and centipede belong to the same group. They have segmented body and jointed legs. Their bodies are covered with exoskeleton.
5.9 Viruses
1. F
2. F
3. F
4. T
5. T
6. F
6 The ecosystem
Part I Check your progress
6.1 What is an ecosystem?
1. population
2. habitat
3. environment
4. community
5. ecosystem
6. ecology
6.2 What is environment?
A. 1. C
2. B
B. 1. T
2. T
3. F
4. T
5. F
6.3 Energy flow within an ecosystem
1. D
2. A
3. D
4. B
5. B
6.4 The accumulation of toxic substances along food chains
(a) parts per million
(b) DDT drained off by water into river (by leaching) is absorbed actively by water plants. A small fish eats a large amount of water plants, and then a large fish eats a lot of small fish, and finally a bird eats a lot of large fish. Since DDT cannot be excreted or broken down, it is accumulated along the food chain.
6.5 Cycling of materials
1. (a) A - respiration B - photosynthesis
C - feeding D – combustion / burning
(b) X is decay. Decomposers are involved in this process.
2. (a) Animals take in plant material, breaking down plant protein into amino acids. Animals synthesise their protein from the absorbed amino acids.
(b) nitrogen fixing bacteria
They are found in the root nodules of leguminous plants.
(c) by decomposition / putrefaction
decomposers / putrefying bacteria
(d) Process C is nitrification.
Nitrifying bacteria are involved.
(e) denitrifying bacteria
6.6 Ecological interdependence of organisms
1. (a) commensalism
2. (b) mutualism
3. (c) predation
(d) predator
(e) prey
4. (f) parasitism
5. (g) competition
7 Effects of humans on the environment
Part I Check your progress
7.1 The increasing effects of human activities on the environment
7.2 Human activities and pollution
A. 1. C
2. A
3. B
4. B
B. 1. (a) humans
(b) pollutants
(c) environment
2. (d) fossil fuels
3. (e) ozone
(f) UV light
4. (g) bacteria
(h) fungi
(i) oxygen
C. 1. F
2. F
3. T
4. T
5. F
6. F
7. T
D. 1. C
2. F
3. G
4. D
5. E
7.3 The Earth's resources
7.4 The undesirable effects of over-exploitation of resources
A. 1. D
2. B
3. C
B. 1. T
2. T
3. F
4. F
5. T
7.5 Environmental protection
A. 1. D
2. D
3. B
B. 1. F
2. T
3. F
4. F
8 Photosynthesis
Part I Check your progress
8.1 How do green plants feed?
8.2 The requirements for photosynthesis
A. 1. C
2. A
B. 1. (a) carbon dioxide
(b) water
(c) solar energy / sunlight
(d) carbohydrates / glucose
(e) Oxygen
2. (f) mesophyll
3. (g) stomata
4. (h) xylem vessels
8.3 Investigations to study the requirement for photosynthesis
A. 1. D
2. D
3. D
B. 1. (a) 1 ® 4 ® 3 ® 2
(b) to soften the leaf
to extract chlorophyll / decolourise the leaf
2. (a) to destarch the plant
(b) (i) to show that carbon dioxide is necessary for photosynthesis
(ii) to absorb carbon dioxide
(c) (i) to show that light is necessary for photosynthesis
(ii) to exclude light / make sure the plant cannot absorb light
(d) Leaf A - blue black, leaves B and C - brown
8.4 The photosynthetic process
A. 1. F
2. T
3. F
B. 1. A
2. B
8.5 The effects of environmental factors on the rate of photosynthesis
A. 1. C
2. C
B. (a) When the distance between the beaker and the table lamp increases, the light intensity decreases. Therefore, the rate of photosynthesis decreases with the increase in distance.
(b) This solution provides carbon dioxide.
(c) A large beaker can hold a greater volume of dilute sodium hydrogencarbonate solution. This provides more carbon dioxide and absorbs more heat energy released by the table lamp.
(d) Crops grow faster in a greenhouse because it is warmer inside. The carbon dioxide concentration in a greenhouse can also be raised to increase the photosynthetic rate of the crops.
8.6 The products of photosynthesis
A. 1. A
2. A
3. D
B. 1. F
2. T
3. F
8.7 Leaves-organs of photosynthesis
A. 1. B
2. A
B. (a) i. veins
ii. cuticle
iii. epidermis
iv. palisade mesophyll
v. spongy mesophyll
vi. xylem
vii. phloem
viii. stoma
(b) 1. Gases can diffuse into and out of the leaf easily.
2. to carry water and minerals from the soil to the leaf
3. to carry the product of photosynthesis away from the leaf
4. for gaseous exchange, to allow carbon dioxide in the atmosphere to diffuse into the leaf
5. to prevent excess water loss
6. for diffusion of gases
9 Respiration
Part I Check your progress
9.1 What is respiration?
A. 1. T
2. T
3. F
4. T
5. T
B. 1. A
2. C
9.2 The use of energy released from food
9.3 The chemistry of respiration
A. 1. F
2. T
3. T
4. F
5. T
6. F
7. F
8. T
B. 1. A
2. D
9.4 Aerobic and anaerobic respiration
A. 1. (a) glucose
(b) carbon dioxide
(c) aerobic
2. (d) ethanol
(e) alcoholic fermentation
3. (f) lactic acid
(g) lactic acid fermentation
B. 1. T
2. F
3. F
4. F
5. T
C. 1. C
2. B
D. (a) food + oxygen ® carbon dioxide + water + energy
(b) oxygen
(c) The oil drop would move towards the boiling tube. The small insect consumes oxygen during respiration and gives out carbon dioxide which is then absorbed by the soda lime. As a result, the air pressure inside the boiling tube becomes lower than the atmospheric pressure and the oil drop moves towards the boiling tube.
10 Obtaining essentials for life in green plants
Part I Check your progress
10.1 Nutrition
1. T
2. F
3. T
4. F
10.2 The importance of minerals for proper growth in green plants
1. (a) active transport
2. (b) major elements
(c) trace elements
3. (d) proteins
(e) nitrates
(f) small leaves
4. (g) chlorophyll
(h) yellowing of leaves
10.3 Fertilizers
1. T
2. T
3. F
4. T
5. T
10.4 Gaseous exchange in plants
A. 1. (a) stomata
(b) diffusion
2. (c) spongy
(d) air space
3. (e) cork cells
(f) lenticels
B. 1. F
2. T
3. F
4. F
10.5 Transpiration
A. 1. D
2. D
3. A
4. C
B. 1. F
2. T
3. T
4. F
5. T
10.6 Absorption of water and mineral salts by the root
1. C
2. E
3. F
4. G
5. D
10.7 Transport in flowering plants
1. F
2. T
3. T
4. F
10.8 Support in plants
(a) turgidity — A and D
rigidity — B and C
The plant will wilt. If the plant is not watered properly, there will be a net loss of water since water is lost by transpiration and the loss is not replenished by water absorption.
11 Food requirements in humans
Part I Check your progress
11.1 Heterotrophic nutrition
11.2 Food and food substances
1. F
2. T
3. T
4. F
11.3 Carbohydrates
A. 1. T
2. F
3. F
4. T
5. F
6. T
B. 1. F
2. C
3. D
4. E
5. B
6. A
11.4 Fats
11.5 Proteins
1. T
2. F
3. F
4. T
5. F
11.6 Vitamins
1. T
2. T
3. F
4. T
5. F
11.7 Mineral salts
11.8 Dietary fibres
11.9 Water
1. A
2. C
3. B
4. D
11.10 Food tests
(a) Clinistix paper
(b) colour changes from pink to blue
(c) Benedict's test
(d) formation of brick-red precipitate
(e) iodine test
(f) colour changes from brown to blue black
(g) Albustix paper
(h) colour changes from yellow to green
(i) spot test
(j) formation of permanent translucent spot
(k) DCPIP test
(l) the blue DCPIP is decolourised
11.11 The need for a balanced diet
11.12 Food and energy
A. Q
S
R
P
B. 1. F
2. F
3. F
4. T
5. T
11.13 The health problems resulting from an improper diet
1. C
2. D
3. B
4. A
12 The Human digestive system
Part I Check your progress
12.1 The processes of nutrition in humans
1. C
2. D
3. E
4. B
5. A
12.2 The human digestive system
(a) oesophagus
(b) duodenum
(c) ileum
(d) appendix
(e) colon
(f) rectum
12.3 The teeth
A. Type of tooth Shape Functions in humans Number in humans
Incisor chisel-shaped biting and cutting 8
Canine pointed tearing 4
Premolar large with uneven surface crushing and grinding 8