Bread is a staple food prepared by baking a dough of flour and water. It is popular around the world and is one of the world's oldest foods. Here the main ingredient is wheat, which is obtained from the plants.

E-mail or electronic mail is a method of exchanging digital messages. These days it is considered as the fastest means of communication as it reaches to the recipient in seconds.

A bullock cart or ox cart is a two-wheeled or four-wheeled vehicle pulled by oxen. It is a medium of transportation used since ancient times.

Pumpkin is a fruit, generally 4–8 kg or more, yellowish to orange in colour. It is a plant that spreads by means of stems that creep. Pumpkin is a weak-stemmed plant that gets its support from climbing, twining or creeping along a surface.

Neptune is the farthest planet, and Mercury is the closest planet. That is why Neptune takes maximum time to revolve around Sun and Mercury takes minimum time.

Plants that move along with water current and do not break are the submerged plants.These plants have small and narrow leaves. They can withstand the strong water currents. They do not have stomata. They breathe through their body surface. They make their food using the carbon dioxide that is dissolved in water.

The seed of this plant is used as a vegetable. The pea is most commonly the small round seed or the seed-pod of the pod fruit. Each pod contains several peas. Peapods are a fruit, however, peas are considered to be a vegetable in cooking.

Plants having roots above the soil are called mangrove plants. Areas with lots of water and sticky soil are called marshy areas. The plants that grow there are called mangroves. Since the soil is soaked in water, the roots of mangroves are unable to take in air from the soil. So, they have breathing roots that arise from the soil. Example: Sundari trees of Sundarban.

Tusks are the teeth of an elephant. They grow seven inches in a year and can be as big as a car. They do not help elephant to chew grass and leaves. An elephant can eat grass and leaves for up to 20 hours per day.

A Parsi is a member of Zoroastrian community in India. Today, very few Parsis are left in India. Their holy book is Zend Avesta. They go to fire temple for worshipping. The fire temple is also called the Agiary.

Hydrilla is a freshwater, aquatic plant that has small narrow leaves. These leaves move along with the water current and do not break. They can withstand the strong currents of water.

An animal, such as a donkey, ox or elephant is used for transporting loads or doing other heavy work. That is why, they are called beasts of burden.

The period between sunset and noon is called morning, between noon and sunset is called afternoon. Generally, the time between sunset and sunrise is approximately 12 hours.

The sun (sunlight), soil, air, rocks and water sources are all non-living things in an ecosystem.

Some trees shed their leaves in winter when season changes. Fresh new leaves appear. This happens because leaves cannot make their food in winter as sunlight is less. So, they let their leaves fall off at one time and are called deciduous plants. Examples: oak, cherry, etc.