Lesson 25 - Changes in our Surroundings
A. What can be done?
Slices of amla are to be kept to dry in a place that receives sunlight all day.
Ans: Slices of amla are to be kept to dry in a place that receives sunlight all day because, in this way, they can be stored for a long period of time.
B. Think and tell.
a. When your shadow is very short, where is the sun in the sky?
Ans: When our shadow is very short, the sun is directly overhead in the sky.
b. What is meant by ‘crescent moon’?
Ans: The smallest shape of the moon is called ‘crescent moon’.
c. After how many days does a new moon follow another new moon?
Ans: A new moon follows another new moon almost thirty days later.
d. Make a list of flowers which bloom in the morning.
Ans: Hibiscus, morning glory, daisies, sunflowers, etc. are some flowers that bloom in the morning.
C. Observe and complete the table.
On a clear day, go to an open field near your school. Find a tall object like a pillar, a tree or a flagpole, or erect a pole in the courtyard of your school. Write your observations in the table.
What do you learn from these observations ? Write your conclusions under the table.
Ans: Students must do this on their own.
D. Fill in the blanks.
(1) Bats are ________ animals.
Ans: nocturnal
(2) When their stomachs are full, cows and buffaloes sit in a peaceful place and ________
Ans: ruminate
(3) ________ are the first to sense the end of the night.
Ans: birds
(4) When the sun rises, its light is ________
Ans: soft
E. Answer the following questions:
(1) When do shadows become long?
Ans: Shadows become longer during the times of sunrise in the morning and sunset in the evening.
(2) What are shadows like when the sun is directly overhead?
Ans: When the sun is directly overhead, the shadow becomes very short.
(3) After the day of the new moon, for how many days does the moon grow bigger?
Ans: After the day of the new moon, the moon grows bigger for almost fifteen days.
(4) Why do bees hover around flowers?
Ans: Bees hover around flowers to collect sweet nectar from them.
F. True or false?
(1) The moon cannot be seen on the day of the new moon.
Ans: True
(2) Some living things set out to search for food after the sun has set.
Ans: True
(3) The day when the moon looks triangular is the day of the full moon.
Ans: False
(4) Birds start chirping at dawn.
Ans: True
(5) The sun gradually shifts towards the east.
Ans: False
G. What are the following called ?
(1) The different shapes of the moon seen every day.
Ans: Phases of the moon.
(2) Animals that rest during the day and search for food at night.
Ans: Nocturnal animals.
(3) The day on which the moon is completely round.
Ans: The day of the full moon.
(4) The day on which the moon cannot be seen.
Ans: The day of the new moon.