An ingredient is a part of a mixture. In food, an ingredient is a specific constituent of the food. For example, in pizzas, cheese is an ingredient. Ingredients vary with different types of food. Ingredients can be obtained from plant sources and animal sources.  

Definition: 1 Mark
Examples: 1 Mark
Plant food products are the different types of food that we get from plants. Green plants are the primary source of food. Examples of plant-based food are vegetables, fruits, cereals, pulses, spices, nuts and oils.

i. True. Butter is made from milk and milk is obtained from animals.
ii. False. Sweet potato is the root of the plant.
iii. True. Groundnut oil is extracted from its seed.

Definition: 1 Mark
Examples: 1 Mark
Animals that do not eat anything except plants are called herbivorous animals. They are also called grass-eating animals.
Examples are cows, goats and deer.

Reasons: 1 Mark each
Any three:
1. Food provides energy.
2. Food is needed for growth.
3. Food helps in maintaining good health.
4. Food maintains body functions.

Food + classification: 1 Mark each

 $\begin{array}{ccc}\text{Animal}& \text{Food}& \text{Classification}\\ \text{Buffalo}& \text{Grass, hay}& \text{Herbivore}\\ \text{Cat}& \text{Mice, milk}& \text{Omnivore}\\ \text{Lion}& \text{Meat}& \text{Carnivore}\end{array}$

Definition: 1 Mark
Methods: 1 Mark each
Animal food source: 1 Mark
Animal food products comprise all the different types of food that we get from animals. Examples are milk, eggs, poultry, meat and honey.
There are different ways of obtaining foods from animals: 

Classifications: 1 Mark each
Human classification: 1 Mark
Based on the type of food eaten by the animals, they are classified into the following four groups: -
1. Herbivores - These animals eat only plants or plant products. E.g. cow, buffalo and deer.
2. Carnivores - These animals eat other animals. E.g. lion, tiger, and wolf.
3. Omnivores - These animals eat both plants/plant products and animals. E.g. bear, fox and skunk.
4. Decomposers - These animals feed on dead plants, dead animals, and rotten materials. Examples: bacteria and fungi.
Based on this classification, humans belong to the group called omnivores.

Parts + example: 1 Mark each.
Most parts of a plant are edible to human beings. The edible parts of some plants are listed below: -
Any 4:
1. Flower - Pumpkin, cauliflower.
2. Seeds - Rice, peas, beans.
3. Leaf - Spinach, cabbage.
4. Stem - Sugarcane, onions, potato.
5. Root - Carrot, beetroot, radish
6. Fruit - Brinjal, guava, mango.