Unit 13 Population & Migration Exercise: Class 10 English Guide

• a. How big was the world population in the middle of 20th century? Question: How big was the world population in the middle of 20th century (approx.)?Answer: 5 billion inhabitants.
• b) The high rate of population growth during the past century. A: The highest rate of population growth over the past century was approximately 2.1 percent per year, which occurred between 1962 and 1965.
• c. What factors contributed to the slowdown in population growth rate in recent years? The rate of natural increase has slowed down in recent decades primarily because fertility, or the number of births, is lower.
• Q: How many people are we expecting to inhabit the globe by 2050? Answer: The world population size is expected to be over 9.7 billion by the year 2050.
• e.) What is the relative contribution of fertility and mortality to the size of population? Explanation: Fertility deals with births, and mortality deals with deaths. And both impact population size. Humans have higher birth rates, resulting in increasing populations; Humans also generate higher mortality rates which can lower population sizes.
• f. What are the source countries of the largest population in Eastern and South-Eastern Asia? Solution: China and India have the largest populations in Eastern and South-Eastern Asia.
• g. Why will Population Region x experience a different pattern/activity of population change over the next 30 years? Response: Population growth patterns are not universal over the next 30-years; they will vary widely by region based on population momentum, among other factors such as fertility and mortality rates.
• H. The countries which will are gaining the maximum contribution in world population by 2050 Q. Which countries will drive world population growth to 2050? A: Democratic Republic of the Congo, Egypt, Ethiopia, India, Nigeria, Pakistan,Philippines and United Republic of Tanzania
• D. Does the population of the world rise according to the graph in text? Discuss. Answer: This kind of world population prediction for the future is always very uncertain and every little variable affects it. While it is predicted that this population will be doubled by the year 2050, such absolute numbers may not accurately reflect what happens if birth rates, public health standards and societal trends were to change. It means that we can somewhat predict but there are a lot of things which will determine if those predictions are right or wrong.

Unit 13 : Reading - II 

Discovering Migration: What Birds Reveal Notes 

• a. What is incredible about the migration of birds? Answer: The incredible thing about the migration of birds is that they fly thousands of miles to their destinations without a roadmap or compass.
• b. What things do birds consider while flying to their destinations? Answer: While flying to their destinations, birds consider changing winds, their own weight, and storms, adjusting their speed, height, and flight path to conserve energy.
• c. Which animals other than the birds migrate to new places? Answer: Other animals that migrate to new places include insects, amphibians, reptiles, fish, and mammals.
• d. What do scoters dive underwater for? Answer: Scoters dive underwater for up to a minute to grab shellfish from the ocean floor.
• e. Which birds migrate up and down rather than north to south Response: Other birds, such as brindled titmice and mountain chickadees use a down-and-up trick rather than a north-south one, migrating from high-elevation evergreen forests to lower elevations.
• f. What is partial migration of birds? A: Partial migration — when not all birds of a species migrate, but some do For instance, in the case of robins, you might see some migrate south for the winter while others reside year-round in the South.
• g. Why don′t sea terns remain long on the water? Answer: Sea terns spend much of their life flying out over oceans but cannot remain for long on the water as their feathers become waterlogged.
• h. How do birds get their food as they travel? Response:To sustain themselves on their travels, birds locate "stopover points" where they can rest and refuel, sometimes spending several days or weeks loading up with energy.
• i. Signs of birds flying in the night sky? Because birds are nearly invisible in the night sky while traveling but become visible when they fly across the moon. Although this method of counting how many migrants fly at night is called moon watching (up to 200 birds per hour!),
• D. Animals migrate to different places, as you may known or heard of it before. Reasons why animals might migrate Discuss. Explanation: Animals migrate to new places to survive, for food, better weather, breeding, avoidance of predators and naturally instictiveness. Migration has been evolved to search for optimal conditions and resources necessary for growth and reproduction.