Life Cycle Of Plant

Chain Reaction

Exercise - Nature's Food Source

A. Write the number of the correct answer in the brackets.

1.	When a dead organism decomposes, ________ is given out.		()
	(1) (2) (3) (4)	oxygen carbon dioxide water bacteria
2.	When a green plant is placed next to a window where sunlight comes in, after a month the stem ________.		()
	(1) (2) (3) (4)	bends away from the window bends toward the window does not bend at all becomes shorter
3.	When iodine solution comes into contact with starch it __________.		()
	(1) (2) (3) (4)	turns from brown to dark blue turns from dark blue to brown remains dark blue remains brownish
4.	A ________ provides the environment necessary for living things to survive.		()
	(1) (2) (3) (4)	place surrounding habitat condition
5.	The excess sugar which a plant produces is converted into________.		()
	(1) (2) (3) (4)	starch energy stem fibre nutrients
6.	Along a food chain, the energy that is stored and transferred from one organism to the next ________.		()
	(1) (2) (3) (4)	becomes more and more remains the same becomes less and less depends on the organism
7.	Food chains are interconnected because animals ________.		()
	(1) (2) (3) (4)	share their food eat more than one type of food eat only other animals depend on one another to survive
8.	Bacteria which live and feed on living organisms are called ________.		()
	(1) (2) (3) (4)	decomposers destroyers body helpers parasites
9.	In this food chain: Maize ---> Mouse ---> Snake		()
	(1) (2) (3) (4)	Snake is prey, mouse is predator. Maize is prey, mouse is predator. Mouse is prey, snake is predator. Mouse and snake are predators.
10.	When plants absorb water from the soil, __________ is also being absored at the same time.		()
	(1) (2) (3) (4)	mineral salts soil iodine methane

B. Write "T" for true and "F" for false.

1.	A tiger is a carnivore.	()
2.	Stomata are found on plant stem.	()
3.	Food is a source of energy for living things.	()
4.	Plants are the start of the food chain.	()
5.	The cutting of trees by man is a great help to the environment.	()
6.	A caterpillar is a herbivore.	()
7.	Fertilizers are derived from the decomposition of dead organisms.	()
8.	Animals like wood lice are not decomposers.	()
9.	Deers eat plants and meat.	()
10.	In a food chain, the population of each organism does not affect the others.	()

C. Fill in the blanks with the most suitable word.

1.	For photosynthesis to occur ____________, ____________, ____________ and ____________ must be present.
2.	Fungi can usually be found on ______________.
3.	In extreme cold conditions, bacteria can exist in an _________ state.
4.	During photosythesis, green plants produce ____________ and ____________.
5.	Bread mould is a type of ____________.

Food Chains

Every living thing needs energy in order to live. Everytime animals do something (run, jump) they use energy to do so.

Animals get energy from the food they eat, and all living things get energy from food. Plants use sunlight, water and nutrients to get energy (in a process called photosynthesis). Energy is necessary for living beings to grow.

A food chain shows how each living thing gets food, and how nutrients and energy are passed from creature to creature. Food chains begin with plant-life, and end with animal-life. Some animals eat plants, some animals eat other animals.

A simple food chain could start with grass, which is eaten by rabbits. Then the rabbits are eaten by foxes.

 

Here's another food chain, with a few more animals. It starts with acorns, which are eaten by mice. The mice are eaten by snakes, and then finally the snakes are eaten by hawks. At each link in the chain, energy is being transferred from one animal to another.

There can be even more links to any food chain. Here another animal is added. It goes Grass to grasshopper to mouse to snake to hawk.

There is actually even more to this chain. After a hawk dies, fungi (like mushrooms) and other decomposers break down the dead hawk, and turn the remains of the hawk into nutrients, which are released into the soil. The nutrients (plus sun and water) then cause the grass to grow.
It's a full circle of life and energy!!

So food chains make a full circle, and energy is passed from plant to animal to animal to decomposer and back to plant! There can be many links in food chains but not TOO many. If there are too many links, then the animal at the end would not get enough energy.

Ecosystems and Biomes

What is ecology about, anyway?

Ecology is the relationship of living things to each other and to what’s around them. So, if you are learning about what kinds of relationships fish have with other animals (including us!) and plants in their neighborhood, then you are learning about ecology. 

The word ECOLOGY comes from Greek words meaning “study of the household.” That means that ecology is the study of the “household” of living things: their neighbors and neighborhood.

Ecology includes not only how living things interact with each other, but how they interact with their physical environment: things such as climate, water, and soil.


Because resources like water and food may be limited, plant and animal species often compete with each other for food and water. The only way that they can all live together is if they occupy slightly different niches or hold different "jobs" in the community. No two species can occupy exactly the same niches They all have their own jobs or niche in the community.

A niche is the smallest unit of a habitat that is occupied by a plant or animal. The habitat niche is the physical space occupied by the plant or animal. The niche is the role the plant or animal plays in the community found in the habitat.

There are lots of different habitat types on Earth. Habitat examples could include lakes, streams, forests, or even a drop of water. All habitats on the Earth are part of the biosphere. Because the Earth is always changing, habitats are constantly changing. Habitats that have similar climate and plants are called biomes .

What is a habitat?

A habitat is a special place where a plant or animal lives. Just like you have a home or place to live, so do animals and plants. When we talk about an animal’s or a plant's home it is more like a neighborhood than a "house." An animal needs five things to survive in its habitat:

• food 
• water 
• shelter 
• air a place to raise its young 

Animals require different amounts of space. Habitats can be big like a forest or they can be much smaller like a burrow. Some animals defend a huge territory or roam over a large area. Some other animals need only a small amount of space and can put up with neighbors that live close. Just like you have to go to the store to get food, an animal leaves its "shelter" to get the things they need to live. If the population's needs aren't met, it will move to a better habitat. Different animals need different habitats. A fish, for example, needs clean water in which to live. A grasshopper, however, needs a big space where it can hop and leaves that it can eat.