igcse biology anwers
ANSWERS
Cambridge
IGCSE® Biology
Practice Book
Answers
1 Characteristics of living things 1 Characteristic
respiration
an increase in size, mass and complexity of an organism
excretion
producing offspring, which prevents extinction of the species sensitivity
this involves feeding
– obtaining nutrients for growth, energy and maintaining health
reproduction
in response to changes, e.g. presence of a predator, to find food or a mate
growth
the ability to detect changes in the surroundings
movement
getting rid of the waste products made by chemical reactions in cells
2 Any suitable sentence with seven words linked to the characteristics of life, e.g. Most Rats Start
Gathering Rice Every Night.
3 Across 5 excretion 6 nutrition 7 respiration Down
1 sensitivity 2 reproduction 3 movement 4 growth
4
Organism plant animal
Product
1 arbon dioxide/ c water
2 oxygen
1 arbon dioxide/ c water
2 urea
(Breathing) is the process of getting oxygen into the lungs and the removal of carbon dioxide.
6 Ref. to faeces being undigested food, which has not been formed through metabolic processes.
Exam focus
Definition the breakdown of food in cells to release energy
nutrition
Process respiration photosynthesis respiration deamination
5 (Respiration) is the release of energy from food substances in cells.
1 B
2 Any three from: movement, excretion, nutrition
(feeding), sensitivity (irritability).
3 (a) Any two from: movement, excretion, sensitivity.
(b) Any two from: growth, reproduction, respiration.
4 Any three from: sensitivity, nutrition, growth, excretion. 2 Classification of living organisms 1 protoctists, fungi, plants, bacteria
2 A (a) (dragonfly) insect (b) ey features – any two from: three pairs
K
of legs, two pairs of wings, one pair of antennae, body divided into three parts, one pair of compound eyes. B (a) (earthworm)
Cambridge
IGCSE® Biology
Practice Book
Answers
1 Characteristics of living things 1 Characteristic
respiration
an increase in size, mass and complexity of an organism
excretion
producing offspring, which prevents extinction of the species sensitivity
this involves feeding
– obtaining nutrients for growth, energy and maintaining health
reproduction
in response to changes, e.g. presence of a predator, to find food or a mate
growth
the ability to detect changes in the surroundings
movement
getting rid of the waste products made by chemical reactions in cells
2 Any suitable sentence with seven words linked to the characteristics of life, e.g. Most Rats Start
Gathering Rice Every Night.
3 Across 5 excretion 6 nutrition 7 respiration Down
1 sensitivity 2 reproduction 3 movement 4 growth
4
Organism plant animal
Product
1 arbon dioxide/ c water
2 oxygen
1 arbon dioxide/ c water
2 urea
(Breathing) is the process of getting oxygen into the lungs and the removal of carbon dioxide.
6 Ref. to faeces being undigested food, which has not been formed through metabolic processes.
Exam focus
Definition the breakdown of food in cells to release energy
nutrition
Process respiration photosynthesis respiration deamination
5 (Respiration) is the release of energy from food substances in cells.
1 B
2 Any three from: movement, excretion, nutrition
(feeding), sensitivity (irritability).
3 (a) Any two from: movement, excretion, sensitivity.
(b) Any two from: growth, reproduction, respiration.
4 Any three from: sensitivity, nutrition, growth, excretion. 2 Classification of living organisms 1 protoctists, fungi, plants, bacteria
2 A (a) (dragonfly) insect (b) ey features – any two from: three pairs
K
of legs, two pairs of wings, one pair of antennae, body divided into three parts, one pair of compound eyes. B (a) (earthworm)