Important points for the reference

CLASSIFICATION OF ANIMALS

Butterflies don't have lungs like humans, but they do have small openings on their bodies called spiracles. Each spiracle has a tiny tube connected to it that  carries oxygen from the  air into the butterfly's body.

 Most of the frogs breathe through skin, but they do have lungs for breathing . When the frogs remain submerged in the water or stay buried in the soil, they only breathe through skin.

1)What is the bone called as which helps us to stand erect? (back bone)

2) What is it made up of? (many smaller vertebrae)  Is it flexible? (yes)

3)What would happen if human being did not have vertebral column in their bodies? (we would not have been able to stand erect and perform so many different tasks like bending and stretching, etc.)

 4) Do you think all the living animals have vertebral column? (no)

5)What do you think animals that do not have vertebral column are called as?(invertebrates)

6)What is the difference between the process of reproduction in a cow and a goose? (A cow gives birth to a calf and a goose lays eggs)

7)List animals that lay eggs and animals that give birth to young ones. (Egg laying animals- hen, duck, pigeon. animals that give birth to young ones- human beings, cat, dog, horse)  Why do you think that some animals reproduce by laying eggs while some give birth to babies? (It is a type of adaptation for survival and reproducing the young ones)

8)Animals like snakes and fish lay eggs, as carrying a baby inside the body increase the weight of the animal. Thus, it would be difficult for these animals to move around for food and other needs (snakes creep, fishes swim, birds fly)

9)The female mammals feed their young ones with milk. (This is why they are called as mammals, because these animals have mammary glands/ milk producing glands)  For e.g.: goat, sheep, cows, dog, tigress, and lioness- all these female animals produce milk to feed their young ones.  Exceptional mammals are:  The Duck-billed platypus, this aquatic mammal lays eggs to reproduce.

- Only female mosquitoes feed on animal blood. Male mosquitoes however feed on the nectar from the plants. Whereas the larval stage of mosquitoes fee on single celled organisms in water-which are neither plants nor animal. However considering the feeding habits in the adult stages of mosquitoes it is safe to consider them as omnivores.

                                                ADAPTATIONS IN ANIMALS

1) Physiological- adaptations in the functions of internal organs of the animal body

2) Physical- external adaptation in an animal  

3) Behavioural- behavioural changes in an animal to adapt with surroundings

Adaptation in animals can differ, i.e. an animal like a chameleon may exhibit physical adaptation which means that it changes its skin colour to hide him in the surroundings. 

Whereas an animal like a rabbit will go into hibernation phase, where it will not perform any task, but just take rest to save on the loss of heat from body.

 Or a snake would use its scales for locomotion, while a fish has fins.

 While animals like cows and buffalos show physiological adaptation by  having four chambered stomach that helps them to consume and store food and chew it later when required to obtain energy.

 Where as a bird has a hollow bone to make it light weight and amphibians have two organs- lungs and moist skin for respiration on land and in water  However few animals and birds show a different kind of adaptation   

Behavioural adaptation- animals like zebra and gazelles migrate to areas with more rainfall in order to stay cool and ensure water availability.

4) How do you think hippopotamus reproduce? (giving birth to young ones) 

5) Is it a vertebrate or an invertebrate animal? (it is a vertebrate animal)

6) Is it a cold or warm blooded animal? (warm blooded animal)

 7) Do you think that hippopotamus can be categorized as an amphibian because it can walk on land as well as swim in water? (yes/no)

8)swim bladder- a gas-filled sac present in the body of many bony fishes, used to maintain and control buoyancy 

9)streamlined- design or provide with a form that presents very little resistance to a·

10) cartilaginous skeleton- skeleton made up of elastic bones·flow of air or water, increasing speed and ease of movement.

11)What characteristic feature do you notice in the body structure of the animal shown here? (the fish has a body that is tapering at the front end and broad in the middle and then gradually becomes less wide towards the rear end) 

12)How is the structure of a fish similar to that of an aeroplane? (an aeroplane has two wings just like the lateral fins of the fish, the aeroplane also has a perpendicular wing at the rear end that is exactly similar to the tail of a fish)

13)  Why do you think they have this kind of body structure? (so that it becomes easy for them to swim in the water)  

VARIETY OF FORCES

Identify the effect of force in each of the following cases:

1) While playing badminton, Joy applied force to the shuttlecock and it went  straight back to the opposite player. (4th affect of force- application of force changes the direction of moving object)  

2) Today morning for breakfast, my mother made chapattis by applying force to the dough. (3rd effect of force- application of force changes the shape of the object)

3)How does surface roughness affect friction? (Rough surfaces generally increase friction, by creating small "catch points" that have to move past each other. In lubricated situations, this makes even more difference because the film of lubricant is uninterrupted by bumps in a smooth surface)  Identify, what is acting as friction in the following cases: 

a.) A parachute falling to the ground. (air)

b.) A snowball rolling down a grassy hill. (grass)