UTTAM SCHOOL FOR GIRLS PSA WORKSHEET GRADE VI SCIENCE

Transcription

1 UTTAM SCHOOL FOR GIRLS PSA WORKSHEET GRADE VI SCIENCE Q. Read the following passages and answer the questions that follow: PASSAGE:1 People are consumers. We have to spend large parts of our days finding, buying, cooking and eating our food. Did you ever think it might be nice to be able to make your own food like plants do? Plants are producers and perform a process called photosynthesis using light from the sun, water and carbon dioxide. Carbon dioxide is the gas we exhale when we breathe. The end result of this chemical reaction is sugar for the plant to eat. The plant releases water and oxygen, a gas all animals need to breathe, into the air. So how do plants do it, and why can t we? Plants have special structures called chloroplasts that animals don t have. Chloroplasts are round, flat organelles that are arranged in stacks called grana. These stacks are filled with chlorophyll. Chlorophyll is what gives leafy green plants their green color. Their main job is to absorb light from the sun. Chloroplasts can absorb every color except green. Light activates the chlorophyll. It creates an energy that splits molecules of water, separating them out into hydrogen and oxygen. Chemical reactions take place. Hydrogen from the water combines with carbon from the carbon dioxide we breathe out. Oxygen is released into the air. People and plants make perfect partners. Plants rely on the carbon dioxide that we breathe out, and we rely on the oxygen that they breathe out. This is one good reason for protecting plant life on Earth. Algae fields near the poles produce a constant supply of oxygen for us. So do the many plants of Earth s rainforests. We need plants in order to survive. Conservation projects around the globe are aimed at protecting our natural resources, including numerous species of plants. Our quality of life and the very quality of the air we breathe depends upon our green plant partners. 1. Plants are also called... a) Producers b) Autotrophs c) Both a and b d) None of these 2. Where do plants get their green colour from? a) Chloroplast b) Chlorophyll c) Photosynthesis d) Grana

2 3. The plants give out...during photosynthesis a) Water and oxygen b) Water and carbon-di-oxide c) Carbon- di-oxide and oxygen d) Sugar and oxygen 4. What is a chloroplast? a) Round flat organelles b) Green pigment c) Stack like structure 5. Plants make food with the help of... a) Sunlight, water and oxygen b) Sunlight, water, carbon di oxide and chlorophyll c) Chlorophyll and oxygen d) Chlorophyll only PASSAGE:2 Most plants are vascular plants, having organized systems for transporting materials around to the various parts of the plant. We all know that the human body has organs in it, like the heart, lungs, and kidneys and so on. But vascular plants have organs, too. The organs in a vascular plant include leaves, roots and stems. Leaves help the plant produce food by gathering sunlight and using it in the process of photosynthesis. The roots help the plant stay in one place. They burrow down into the ground and hold on. The roots also absorb nutrients and water out of the ground that the plant can use. Stems hold water, and help support the plant. They also act as a highway system to help plants get what they need. There are two kinds of vascular tissue inside the plant s organs: xylem and phloem. Xylem carries water and nutrients through the plant from the roots to the stem and leaves. Xylem always flows up, not down. After sugar is made in the leaves during the process of photosynthesis, phloem picks up the sugar and carries it throughout the plant. The natural direction of phloem is downward, but it can flow upward when it has sugar to deliver. Sometimes the plant needs to use the sugar right away. At other times, the sugar is stored to be used later. Vascular tissue is found in clusters in most plants, with xylem and phloem packaged together. It takes a certain amount of pull to make water flow up a plant. Root pressure gets the process started. Roots tend to be salty, which draws water in. The special tissue of the roots prevents the water from going back out. Water drops cling to each other, and to some other molecules. This property of water is called cohesion. But even root pressure and cohesion are not enough. Transpiration is the final piece that keeps things moving. As water evaporates off of the plant s leaves, it pulls more water up through the plant to take its place. In fact, almost all of the water that flows through a plant moves up through the plant fairly quickly and is transpired.

3 1...transports water and minerals from root to the plant a)xylem b)phloem c) stem d) leaves 2...transports food prepared by leaves to other parts of plant. a)xylem b) Phloem c) Stem d) Roots 3.The three primary organs in a vascular plant are a)heart, lung, kidney b) roots, leaves, stem c) roots, flowers, stems d)flower, leaves,stem 4 Food prepared by leaves is in the form of... a)glucose b)starch c) chlorophyll d) water 5. What is transpiration? a) Opening and closing of stomata b) Evaporation of water from the leaves c)making food for the plant d) Trapping insects for food PASSAGE:3 Living things adapt to their environment so they can survive. An organism adapts when it develops a behaviour that makes it more likely to survive. It can also adapt by forming a physical characteristic or body part that helps it survive. In a forest biome, some trees grow taller than the other plants around them. This lets them reach the sunlight. Growing taller is an adaptation that helps trees survive. Shorter plants have adapted with their behaviour. They have learned to live in the shade with less sunlight. Animals in the forest have a wide variety of adaptations. Monkeys have long tails. They can use them almost like another hand. This helps them swing quickly through the tops of trees. They can even do this while holding their babies or gathering food. Giraffes need to reach leaves at the tops of tall trees. Having a long neck is an adaptation that allows them to do this.

4 Some animals adaptations prevent other animals from wanting to eat them. A skunk s horrible smell makes larger animals choose something else to eat. Even plants sometimes protect themselves in this way. Roses and acacia trees both have dangerous thorns. The thorns prevent animals from eating their leaves. 1) The main ways by which an organism adapts are... a) By changing its behavior b) By changing its physical characteristics c) Both a and b d) None of these 2) Which one of the following is not a habitat? a) water lily and fish in lake b) chairs and tables in a restaurant c) trees and birds in forest d) cacti and camel in a desert 3) Which of these plants are adapted to live in a desert? a) Ferns b) Cactus c) Coconut d) Lotus 4) What is the habitat of sharks? a) Lakes b) Rivers c) Oceans d) Ponds 5) Which of these is not an abiotic component? a) Microorganisms b) Air c) Rocks d) Sunlight 6) Which of these is not an adaptation in Carnivores? a) Strong legs with sharp claws b) Strong grinding teeth c) Strong and sharp teeth d) Sharp eyesight

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