GENERAL KNOWLEDGE QUIZ-SCIENCE 2

                                NCERT 7 TH CLASS QUIZ FOR EXAM ASPIRANT 

ANSWER THE FALLOWING QUESTION (1-5)-Chapter 1 of 7 th class NCERT
(1) Green plants synthesise their own food because they are
(a) autotrophs
(b) heterotrophs
(c) None of the above

(2) The food synthesised by the plants is stored as
(a) Guard cells
(b) chlorophyll
(c) Stomata

(3) In photosynthesis solar energy is captured by the pigment called
​(a) chlorophyll
(b) Stomata
(c) Leaf
​
(4) The plant which traps and feeds on insects is
(a) Cuscuta
(b) china rose
(c) pitcher plant

(5) Which part of the plant takes in carbon dioxide from the air for photosynthesis ?
(a) Root hair
(b) Stomata
(c) Leaf veins

EXPLANATION(1-5)

Q.1) Answer(a) 
Green plants synthesise their food themselves by the process of photosynthesis. They are autotrophs.

Q.2) Answer(b) 
The leaves have a green pigment called chlorophyll. It helps leaves to capture the energy of the sunlight. This energy is used to synthesise (prepare) food from carbon dioxide and water. Since the synthesis of food occurs in the presence of sunlight, it is called photosynthesis (Photo: light; synthesis : to combine). So we find that chlorophyll, sunlight, carbon dioxide and water are necessary to carry out the process of photosynthesis. It is a unique process on the earth. The solar energy is captured by the leaves and stored in the plant in the form of food. Thus, sun is the ultimate source of energy for all living organisms.

Q.3) Answer(a) 
The leaves have a green pigment called chlorophyll. It helps leaves to capture the energy of the sunlight. This energy is used to synthesise (prepare) food from carbon dioxide and water. 

Q.4) Answer(a) 
This is a plant called Cuscuta (Amarbel). It does not have chlorophyll. It takes readymade food from the plant structure is the modified part of the leaf. The apex of the leaf forms a lid which can open and close the mouth of the pitcher. Inside the pitcher there are hair which are directed downwards. When an insect lands in the pitcher, the lid closes and the trapped insect gets entangled into the hair. The insect is digested by the digestive juices secreted in the pitcher. Such insect-eating plants are called insectivorous plants.

Q.5) Answer(b)
Carbon dioxide from air is taken in through the tiny pores present on the surface of the leaves. These pores are surrounded by ‘guard cells’. Such pores are called stomata

ANSWER THE FALLOWING QUESTION (6-10)Chapter 1 of 7 th class NCERT
(6) Which part of the plant takes in carbon dioxide from the air for photosynthesis ?
(a) Root hair
(b) Stomata
(c) Leaf veins

(7) Plants take carbon dioxide from the atmosphere mainly through their 
(a) roots
(b) stem
(c) leaves

(8) Which of the fallowing statement true
(1) Carbon dioxide is released during photosynthesis.
(2) Plants which synthesise their food themselves are called saprotrophs.
(a) only 1
(b) only 2
(c) None of the above

(9) During photosynthesis plants take in and release
(a) carbon dioxide and oxygen 
(b) Nitrogen and oxygen 
(c) carbon dioxide and Hydrozen

(10) Which of the fallowing statement true
(1) Animals  are heterotrophs​
(2) The leaves have a green pigment called chlorophyll
(3) Water and minerals present in the soil are absorbed by the roots and transported to the leaves.
(4) Carbon dioxide from air is taken in through the tiny pores present on the surface of the leaves. These (5) pores are surrounded by ‘guard cells’. Such pores are called stomata
(6) The carbohydrates ultimately get converted into starch. The presence of starch in leaves indicates the occurrence of photosynthesis.
(a) 1,2,3,5 and 6
(b) 2,3,4,5 and 6
(c) 1,2,3,4,5 and 6

EXPLANATION(6-10)

Q.6) Answer(b)
Leaves are the food factories of plants. The synthesis of food in plants occurs in leaves. Therefore, all the raw materials must reach there. Water and minerals present in the soil are absorbed by the roots and transported to the leaves. Carbon dioxide from air is taken in through the tiny pores present on the surface of the leaves. These pores are surrounded by ‘guard cells’. Such pores are called stomata.

Q.7) Answer(c)
Plants take carbon dioxide from the atmosphere mainly through their leaves.Leaves are the food factories of plants. The synthesis of food in plants occurs in leaves. Therefore, all the raw materials must reach there. Water and minerals present in the soil are absorbed by the roots.
Q.8) Answer(c)
leaves  capture the energy of the sunlight. This energy is used to synthesise (prepare) food from carbon dioxide and water.
The mode of nutrition in which organisms make food themselves from simple substances is called autotrophic (auto = self; trophos = nourishment) nutrition. Therefore, plants are called autotrophs. Animals and most other organisms take in ready made food prepared by the plants. They are called heterotrophs

Q.9) Answer(a)
Carbon dioxide taken from air and oxygen is released into atmosphere by plants.

Q.10) Answer(c)
Animals and most other organisms take in ready made food prepared by the plants. They are called heterotrophs​.
The leaves have a green pigment called chlorophyll. It helps leaves to capture the energy of the sunlight. This energy is used to synthesise (prepare) food from carbon dioxide and water.
Water and minerals present in the soil are absorbed by the roots and transported to the leaves.Carbon dioxide from air is taken in through the tiny pores present on the surface of the leaves.These pores are surrounded by ‘guard cells’. Such pores are called stomata
The carbohydrates ultimately get converted into starch. The presence of starch in leaves indicates the occurrence of photosynthesis.

ANSWER THE FALLOWING QUESTION (11-15)Chapter 2 of 7 th class NCERT
(11) The largest gland in the human body is
(a) salivary glands
(b) small intestine
(c) stomach

(12) Amoeba digests its food in the
(a) Nucleus
(b) Pseudopodium
(c) Food vacuole

(13) Fat is completely digested in the
​(a) stomach
(b) mouth
(c) small intestine
​
(14) Water from the undigested food is absorbed mainly in the
(a) stomach
(b) small intestine
(c) large intestine

(15) Match the fallowing
(a) Salivary gland              (1) Bile juice secretion
(b) Stomach                       (2) Storage of undigested food
(c) Liver                               (3) Saliva secretion
(d) Rectum                         (4) Acid release
(e) Small intestine            (5) Digestion is completed
(f ) Large intestine            (6) Absorption of water
                                             (7) Release of faeces
EXPLANATION(11-15)

Q.11) Answer(b) 
The small intestine is highly coiled and is about 7.5 metres long. It receives secretions from the liver and the pancreas. Besides. It is the largest gland in the body.
The liver is a reddish brown gland situated in the upper part of the abdomen on the right side.It secretes bile juice that is stored in a sac called the gall bladder. The bile plays an important role in the digestion of fats.
The pancreas is a large cream coloured gland located just below the stomach. The pancreatic juice acts on carbohydrates, fats and proteins and changes them into simpler forms.

Q.12) Answer(c) 
Amoeba is a microscopic single-celled organism found in pond water. Amoeba has a cell membrane, a rounded, dense nucleus and many small bubble-like vacuoles in its cytoplasm. Amoeba constantly changes its shape and position. It pushes out one, or more finger-like projections, called pseudopodia or false feet for movement and capture of food.
Amoeba feeds on some microscopic organisms. When it senses food, it pushes out pseudopodia around the food particle and engulfs it. The food becomes trapped in a food vacuole
Digestive juices are secreted into the food vacuole. They act on the food and break it down into simpler substances. Gradually the digested food is absorbed. The absorbed substances are used for growth, maintenance and multiplication. The undigested residue of the food is expelled outside by the vacuole.

Q.13) Answer(c) 
 Fat is completely digested in the small intestine

Q.14) Answer(c) 
The large intestine is wider and shorter than small intestine. It is about 1.5 metre in length. Its function is to absorb water and some salts from the undigested food material. The remaining waste passes into the rectum and remains there as semi-solid faeces. The faecal matter is removed through the anus from time-to-time.​

Q.15) Answer(a-3 , b-4, c-1, d-7, e-5, f-6)

• Our mouth has the salivary glands which secrete saliva.
• The stomach is a thick-walled bag. Its shape is like a flattened U and it is the widest part of the alimentary canal. It receives food from the food pipe at one end and opens into the small intestine at the other. The inner lining of the stomach secretes mucous, hydrochloric acid and digestive juices. The mucous protects the lining of the stomach. The acid kills many bacteria that enter along with the food and makes the medium in the stomach acidic and helps the digestive juices to act. The digestive juices break down the proteins into simpler substances.
• The liver is a reddish brown gland situated in the upper part of the abdomen on the right side. It is the largest gland in the body. It secretes bile juice that is stored in a sac called the gall bladder. The bile plays an important role in the digestion of fats.
• The remaining waste passes into the rectum and remains there as semi-solid faeces. The faecal matter is removed through the anus from time-to-time.
• The small intestine receives secretions from the liver and the pancreas. Besides, its wall also secretes juices. The liver is a reddish brown gland situated in the upper part of the abdomen on the right side. It is the largest gland in the body. It secretes bile juice that is stored in a sac called the gall bladder . The bile plays an important role in the digestion of fats. The pancreas is a large cream coloured gland located just below the stomach. The pancreatic juice acts on carbohydrates, fats and proteins and changes them into simpler forms.The partly digested food now reaches the lower part of the small intestine where the intestinal juice completes the digestion of all components of the food. The carbohydrates get broken into simple sugars such as glucose, fats into fatty acids and glycerol, and proteins into amino acids.
• The large intestine is wider and shorter than small intestine. It is about 1.5 metre in length. Its function is to absorb water and some salts from the undigested food material. The remaining waste passes into the rectum and remains there as semi-solid faeces.

ANSWER THE FALLOWING QUESTION(16-20)Chapter 3 of 7 th class NCERT

(16) The silkworm is (a) a caterpillar, (b) a larva. Choose the correct option.
(a) a
(b) b
(c) both a and b
(d) neither a nor b

(17) Which of the following does not yield wool ?
(a) Yak
(b) Camel
(c) Goat
(d) Woolly dog

(18) The rearing of silkworms for obtaining silk is called
(a) Rearing
(b) Shearing
(c) Sericulture

(19) Out of the following, which are the two terms related to silk production ?
(a) Sericulture, floriculture, 
(b) Sericulture, moriculture, 
(c) Sericulture,  silviculture

(20) Match the words of Column I with those given in Column II:
Column I                                          Column II
1. Scouring                                          (a) Yields silk fibres
2. Mulberry leaves                             (b) Wool yielding animal
3. Yak                                                    (c) Food of silk worm
4. Cocoon                                            (d) Reeling
                                                              (e) Cleaning sheared skin

EXPLANATION(16-20)

Q.16) Answer(a)
The female silk moth lays eggs, from which hatch larvae which are called caterpillars or silkworms. They grow in size and when the caterpillar is ready to enter the next stage of its life history called pupa.

Q.17) Answer(d) 
Silk comes from silkworms and wool is obtained from sheep, goat and yak. Hence silk and wool are animal fibres.The hairs of camel, llama and alpaca are also processed to yield wool.In India, mostly sheep are reared for getting wool.

Q.18) Answer(c)
Silk fibres are also animal fibres. Silkworms spin the ‘silk fibres’. The rearing of silkworms for obtaining silk is called sericulture.Soon the caterpillar completely covers itself by silk fibres and turns into pupa. This covering is known as cocoon.Thus different type of silk are  mulberry silk, tassar silk, mooga silk, kosa silk, etc.

Q.19) Answer(b)
Sericulture, moriculture

Q.20) Answer(1-e , 2-c, 3-b, 4-a)

• The sheared skin with hair is thoroughly washed in tanks to remove grease, dust and dirt. This is called scouring. Nowadays scouring is done by machines
• Mulberry leaves-Food of silk worm
• Wool comes from sheep, goat, yak and some other animals.Several breeds of sheep are found in different parts of our country. However, the fleece of sheep is not the only source of wool, though wool commonly available in the market is sheep wool.Yak wool is common in Tibet and Ladakh. Angora wool is obtained from angora goats, found in hilly regions such as Jammu and Kashmir.Wool is also obtained from goat hair. The under fur of Kashmiri goat is soft. It is woven into fine shawls called Pashmina shawls. The fur (hair) on the body of camels is also used as wool. Llama and Alpaca, found in South America, also yield wool.
• The silk yarn (thread) is obtained from the cocoon