What is the difference between Plants and Animals?
Plants:
1. Cell Wall:
Each plant cell is surrounded by a distinct non-living ,i.e., dead and rigid wall.
2. Cellulose:
The plant cellwall is made up of a chemical substance, known as cellulose.
3. Chlorophyll:
The green colour of the plant is due to the presence of a pigment called cholorophyll. However, fungai and bacteria lack this pigment.
4. Centrosomes
Centrosome is a star-shaped body present in the cytoplasm near the nucleus. It is not seen in the cells of seed plants. Some plants may possess such bodies.
5. Vacuoles
These are small or large spaces present in the cytoplasm. They are smaller in size and lesser in number in young cells. But in mature cells vacuoles are very conspicuous and contain liquid called ‘Cell-sap’. The membrane bordering a vacuole is known as tonoplast.
6. Food
(i) A green plant cellcan manufacture its own organic food substances from simple substances as CO2, water, minerals etc. with the help of chlorophyll in the presence of light; hence plants are autotrophic.
(ii) Plants cannot absorb solid food.
7. Utilization of CO2
Green plants can utilize the atmospheric carbon dioxide in manufacturing sugar by the process of photosynthesis. However, all fungi and heterotrophic bacteria lack this property.
8. Mode of nutrition
The intake of food materials by plant is through absorption from solution only. Thus the mode of nutrition in plants is called ‘holophytic’.
9. Organ system
Plants do not have definite and organized system such as digestive, respiratory, excretory, nervous and reproductive etc. However, higher plants possess organs like root, stem, leaf and flowers.
10. Movements
(i) Higher plants are fixed to the soil and are incapable of movement. Only certain microscopic plants can move in water. However, plant parts move in response to stimuli, such as light, water and gravity.
(ii) Induced movement, i.e., response to stimuli is slow.
11. Growth
(i) The regions of growth are localized i.e., seen at definite regions like tips of stems and roots.
(ii) Growth proceeds until death i.e., growth and development take place throughout life.
(i) Higher plants have a branching system and diffusing form and show an indefinite scheme of growth.
12. Reproduction
In addition to usual sexual mode of reproduction, plants reproduce by vegetative means. Stem-cuttings, root-cuttings and sometimes leaves give rise to new plants similar to the parent ones. Lower plants multiply by fragmentation of the parent body.
Animals:
1. Cell Wall:
Animals cell lacks a cell wall.
2. Cellulose:
Cellulose is entirely absent in the animal cell.
3. Chlorophyll:
Cholorophyll is totally absent in animal cells, but a green pigment is present in some cases like Euglena.
4. Centrosomes:
These occure as a spherical body associated with the nucleus of the animal cells.
5. Vacuoles:
Vacuoles are absent or scarcely seen in animal cells.
6. Food:
i. An animal cell has no power to manufacture its own food. Animals depend either directly or indirectly on plants for their food material; hence they are heterotrophic.
ii. Animals can take solid food.
7. Utilization of CO2:
Animals lack this power of utilizing CO2 or of manufacturing food.
8. Mode of nutrition:
Animals can take in food substances in solid form which is ingested through an opening. This mode of nutrition is called ‘holozoic’.
9. Organ system:
Higher animals possess various organs of locomotion, respiration, excretion, reproduction and nervous system for efficient functioning. However, lower animals lack these.
10. Movements:
i. Animals can move freely except in a few cases like sponges and corals.
ii. Response to stimuli is rapid.
11. Growth:
i. All parts grow simultaneously and hence growth is not localized to any definite region.
ii. Growth ceases long before death, i.e., it stops at a certain age.
iii. Growth is definite and uniform. So the animals have a compact form of body.
12. Reproduction:
Sexual mode of reproduction is prevalent in animals. However, some lower animals like Amoeba multiply by fragmentation.