GENERAL SCIENCE STD - SEVEN BOOK QUESTIONS

 GENERAL SCIENCE 

    STD - SEVEN

    Can you tell ?

    Chapter No. 1 - 

The Living world: Adaptations Classification

          1.     In what different ways is the diversity in living things seen?

      Ans – The diversity in the living things is seen due to their different shape, size, color and different structure of the body.

         2.     Are the plants and animals from Kashmir and Rajasthan of the same type? Can you elaborate on any differences between the two?

    Ans – Kashmir and Rajasthan are geographically different terrains. The climatic conditions are different in these two places. Therefore, the flora (all the plants) and fauna (all animals) is also different. Animals in Kashmir are with thick fur. Their body is changed to suit the cold climate. Rajasthan being the desert, animals like camel are seen here. According to local conditions, the plants and animals show different characteristics.

         3.     Observe and complete the chart.

     Ans -

Plant	Habitat	Type of root	Characteristics of leaves	Characteristics of stem
Lotus	Aquatic	Fibrous	Large and round with waxy layer	Hollow and flexible
Cactus	Desert	Deeply penetrating	Cannot see leaves or like small needles or modified into thorns	Thick, fleshy, green stem
Banyan	Land	Some in soil and some in aerial	Big and Green	Hard, tall and Brown in color

    

          4.     Why does water trickle off lotus leaves?

     Ans – Lotus is an aquatic plant that has coating of waxy layer on its stem and leaves. If water falls on the leaves, it is not absorbed but gets trickled down.

         5.     Why don’t the leaves of these plants rot in water?

     Ans – The leaves of aquatic plants have waxy coating on them. There are no stomata on the leaves and thus water cannot enter the leaves. Therefore, the leaves of these plants do not rot in water.

         6.     Why are their roots short and fibrous?

     Ans – The main function of the roots is to hold the plant firmly and to absorb the water and minerals for the plant. Both of these functions are not needed for the plant like Lotus which floats on the water. Therefore, their roots are short and fibrous.

         7.     In what way are sloping branches useful to plants in a snowy region?

     Ans – The snow should naturally fall off from the branches and should not remain on the tree top. Therefore, as an adaptation, the plants in a snowy region have sloping branches.

         8.     Observe the bodies of the frog, duck and tortoise. Of what use are their legs to these animals?

     Ans – These animals have webbed toes, they can use their legs like oars.

         9.     What helps frogs to breaths underwater?

     Ans – Frogs ability to breathe through the skin in underwater.

    

         10. Of what use are the long hind legs of a frog?

     Ans – The long hind legs of a frog to swim easily through water and jump long on land.

          11. Why doesn’t a duck get wet in water?

      Ans – Water flows off the waxy feathers of duck. That’s of duck does not get wet in water.

          12. What is the main difference between vehicles on the road and aeroplanes?

      Ans – Vehicles on the road have wheels. Aeroplanes have wings.

          13.  Complete the following chart from your own observations.

     Ans -

Adaptation	Animal	Use of adaptation
Sharp teeth	Lion, tiger	To tear the flesh
Long and pointed beak	Kingfisher, crane	To capture the fish in water
Short beak	Sparrow, Pigeon	To peak the grain
Long and sticky tongue	Garden lizard, frog	To catch the insects
Long neck	Giraffe, Camel, Emu, Ostrich	Birds: To have a long distance gaze. Giraffe, Camel: To eat leaves from the top of the tree.

           14. Why are living things classified?

       Ans – It is difficult to study and remember all the organisms in this diverse living world at the same time. Classification is helps to them.

           15. Which are the criteria used for classification of plants and animals?

       Ans – Different scientists have used different criteria and independently classified plants and animals. Plants are classified according to height, shape of stems, period of life cycle, whether they are flowering plants or non-flowering plants and their habitat.

Animals are classified according to cell structure, vertebral column, method of reproduction and habitat.  

           16. Find out the scientific names of other animals and plants in your surroundings and discuss in class.

       Ans –

Living Things	Scientific Name
Dog	Canis lupus familiaris
Cow	Bos taurus
Hibiscus	Hibiscus rosa-sinensis
Jowar	Sorghum bicolor
Human	Homo sapiens
Mango	Mangifera indica
Wolf	Canis lupus
Lion	Panthera leo
Elephant	Elphas maximus
Peacock	Pavo cristatus
Tiger	Panthera Tigris
Horse	Equus caballus
Zebra	Equus quagga
Buffalos	Babalus bubalis
House wall Lizard	Hemidactylus flaviviridis
Cat	Felis domesticus
Rabbit	Oryctolagus cuniculus
House sparrow	Passer domesticus
Indian parrot	Psittacula eupatria
Pigeon	Coumba livia

2. Plants: Structure and Function

      1.     What helps us to easily identify the plants around us?

Ans – We have to easily identify the plants with help of its leaves, flowers, fruits, stem, and shape of plants.

      2.     Which are the various parts of plants?

Ans – Roots, stem, leaves, flowers and fruits are the various parts of plants.

     3.     What would have happened if plants like tamarind, banyan and mango had fibrous roots?

Ans – Tamarind, banyan and mango are huge trees with a grand canopy of leaves. The roots these plants should be strong enough to support these trees. If they had fibrous roots, the trees will be uprooted and fallen down.

      4.     What will happen if the root-tip is injured?

Ans – If the root tip is injured, the growth of the plant will be stop or stunted. Initially the tree will try to survive but injured root may not absorb water and minerals from the soil. This will make the tree weak. If the root tip is injured the root is rot easily in water. The support of the tree will also become insufficient and the tree will eventually die.

      5.     Which types of roots do the fenugreek, spinach and onion plants have?

Ans – Fenugreek has tap root but it does not traverse deep down in the soil. Spinach also has tap root which bear many secondary roots. Some of these are seen growing horizontally in the soil. Onion has fibrous roots. They emerge from disc shaped structure which is modified stem.

     6.     Why are the underground parts of plants like radish, carrot, beet and sweet potato thick, fleshy and swollen? Which part of the plant are they?

Ans – Underground parts of any plant are called as root. Roots of radish, carrot, beet and sweet potato are called Tuberous roots because they are thick, fleshy & swollen. These special roots store the nutrients and hence appear thick, fleshy and swollen. Tuberous roots can be further classified into simple tuberous roots and fasciculate tuberous roots.

      7.     Complete the chart. (Collect information about other local plants, too.)

Ans –

Name of Plant	Thickness (circumference) of node (mm)	Length of internode (mm)
1.     Sugarcane	31.42 cm	2000mm – 3000mm
2.     Fenugreek	1.03 mm to 1.15 mm	20 cm – 30 cm