(a) (i) List three characteristics of living organisms. (ii) Explain briefly the characteristics listed in...
(a) (i) List three characteristics of living organisms.
(ii) Explain briefly the characteristics listed in (a)(i) above.
(b) In a tabular form, state four differences between plants and animals.
(c)(i) Name one organism that exhibits both plant and animal features.
(ii) State four animal features and two plant features possessed by the organism named in (c)(i) above.
Explanation
(a)(i) Characteristic of Living organisms:
- Movement/locomotion
- Excretion
- Respiration
- Reproduction
- Irritability/sensitivity/response
- Growth/development
- Nutrition/feeding
- Competition
- Adaptation
- Life span/death
(ii)Movement: Living things change the position of the whole body/parts of the body; from one place to another; in search of food/shelter/mates, etc.
Excretion: This involves the removal/getting rid of waste products of cell metabolism; membole wastes are poisonous if allowed to accumulate.
RespirationThis is the breakdown/burning of food substances; by aerobic/anaerobic respiration; to release energy needed for all processes of life.
Reproduction: This is the ability of living organisms to produce new individuals of their own kind; this ensures the continuity of the species of an organism.
Irritability: Response/ reaction of organisms; towards changes in the environment; to ensure survival. Nutrition: the process involved in obtaining/manufacturing food; can be autotrophic/heterotrophic; and utilizing it for growth and maintenance/life processes.
Growth: This is the irreversible increase; in size and weight of an organism; which leads to complexity and maturation.
Competition: Ability of organisms to struggle; for all necessity of life; to survive in their environment.
Adaptation: Ability of organisms to adjust; to changes in environment; for survival.
Life span/death:All living organisms have definite period of existence; all organisms die.
b Differences between plants and animals;
| Animals | plants |
| move from place to place, locomotion, move with the whole body | Are fixed/do not move from place to place, and move only parts of the body, root/stem/leaf |
| Heterotrophic mode of nutrition that depend on already-made food | Autotrophic mode of nutrition/ manufacture their own food using the energy from the sun |
| No chlorophyll/chloroplast | chlorophyll/chloroplast present |
| No cell wall | Has a cell wall made of cellulose |
| sense organs present | sense organs absent |
| Growth is limited/definite, growth in all parts of the body | growth is unlimited/indefinite .growth is apical or terminal |
| stores carbohydrates as glycogen | stores carbohydrates as starch |
| Has special excretory body | No special excretory body |
| Response is fast, short termed | response very slow/short termed |
| Respiratory organs present | No respiratory organs |
(c)(i) Name of organism:
Euglena/Chlamydomonas.
(ii) Animal features: For Euglena
— Gullet for feeding.
— Has flagellum for locomotion in water.
— Myonemes for movement.
— Has pellicle that gives it a definite shape.
— Has eye spot to detect light intensity.
— Has contractile vacuole for osmoregulation and excretion.
Plant features:
- Definite shape.
— Has chioroplasts containing chlorophyll used to absorb light.
— Paramylum granules.
— Pyrenoid.