Class Notes NCERT Solutions for CBSE Students
NCERT 7th Class (CBSE) Science: Weather, Climate and Adaptations of Animals to Climate
Question: What does a meteorologist do?
Answer: A meteorologist is a person who prepares the weather report by collecting information on temperature, wind, humidity, rainfall etc. and predicts the weather conditions of a particular place.
Question: What are the common adaptations in animals living in deserts?
Answer: Hot and dry climates have very high temperature during most part of the year. Winter lasts for a few months during which the temperature is quite low. These regions receive very little rainfall and have a typical desert climate.
- Camels are especially adapted to these climates as they can survive the harsh conditions of the deserts. They are adapted to excrete very less urine to reduce the loss of water. They can also drink large quantities of water and eat plenty of food which can be stored in their hump for later use. Hence, they can survive without water and food for days while travelling in the desert. Their bodies are also adapted to tolerate temperature changes such as heat in the daytime and cold in the night time. Camels have the ability to close their eyes and nostrils to keep out the blowing sand and dust in the desert. They have three eyelids that prevent the sand from entering their eyes.
- Many reptiles and other animals protect themselves from the extreme temperature by spending their time in burrows during the day and become active at night (being nocturnal).
- Some animals such as rat, salamander and tortoise cannot cope with the heat and so undergo aestivation (summer sleep) to escape the heat.
- Kangaroo rat spends its days in burrows where the air is moist and humid.
Weather, Climate and Adaptations of Animals to Climate – Question: List factors that affect the climate of a place?
Answer:Factors that affect the climate of a place are:
- Distance from the Equator: Different parts of the Earth receive different amounts of heat from the sun. The amount of heat received depends upon the distance of latitude from the equator. Places located at high latitudes (far from the equator) receive less sunlight resulting in cold climates than those at low latitude (close to the equator) making areas near the equator very warm.
- Height above the sea level: The climate of a place is influenced by the height of the place above the sea level, which is known as altitude. Mountains are cooler as the air is thin and is not able to absorb and retain much heat. Plains are warmer than mountains as the air is thicker and absorbs and retains heat.
Question: List factors that affect the climate of the Earth?
Answer: The Earth has three basic types of climate: tropical, temperate and polar. Factors that affect the climate of the Earth are:
- Distance from the sun: The farther the Earth is from the sun, the lesser the heat obtained from the sun. As the earth revolves around the sun only one hemisphere is closer to the sun at a time. So, when the North Pole is towards the sun, it is warmer than the South Pole, and vice versa.
- Tilt: The Earth’s axis is not perpendicular to the plane of its orbit. It is inclined at an angle of 23.5°. This causes the northern hemisphere to receive the maximum direct sunlight. Thus, it gets more hours of daylight in June than in December when it receives lesser direct sunlight and lesser hours of daylight. This causes different seasons in a year. In contrast, in the southern hemisphere the seasons are reversed. When the seasons are reversed in the southern hemisphere, the North Pole is tilted away from the sun; the South Pole is tilted towards it therefore, it is summer in the southern hemisphere. If the Earth did not have a tilt, there would be no seasons and day and night would be of the same length all through theyear.
- Sunrise and sunset: As the Earth revolves on its axis (an imaginary line passing through both the north and south poles) once a day. It gives the appearance of sunrise or sunset.
Question: Differentiate between Weather and Climate with examples.
Answer: Difference is as follows:
Weather
Climate
1. Weather is the day-to-day atmospheric condition at a place with respect to temperature, humidity, rainfall, wind speed, etc.
2. When the average weather pattern prevails over a long period of time in a place, we call it the climate of that place.
1. For example, if on one day the weather is cloudy and cool, there are chances that the next day it may be sunny and warm. Sometimes during the day, mornings may be sunny and warm but by evening it may become cloudy and rain heavily.
2. For example, the Himalayan region is said to have a cold climate because its weather has been extremely cold for centuries. Similarly, the Western Ghats have had a humid and tropical climate for years.
