NCERT Solutions for Class 12 Biology Chapter 7 – Evolution
NCERT Solutions for Class 12 Biology Chapter 7 – Evolution is carefully drafted by best Biology experts. This chapter gives you a crucial understanding of the basic concepts of evolution in details. It will familiarise with you with various evolution theories and help you understand the origins of life on earth. This chapter of NCERT Solutions for Class 12 Biology helps you find answers to important questions like how did life forms evolve and what evidence makes us believe in evolution. Here you will study Darwin’s Theory of Evolution and Hardy Weihberg’s Theory. This chapter also covers concepts like adaptive radiation and antibiotic resistance.
There are a total of 10 questions asked at the end of the chapter covering all the concepts taught in NCERT CBSE Class 12 Biology Chapter 7. The questions given in the chapter enable you to revise the learn even the most complex concepts easily and systematically. Our NCERT Solutions answer all questions of the exercise in a step by step manner. They follow the guidelines given by CBSE and NCERT. These are easy to understand, comprehensive yet precise, and hundred per cent accurate solutions that help you learn effectively. They help you save time and effort. Our Class 12 Biology Evolution Solutions are beneficial for quick and effective revision during your board exams.
CBSE NCERT Class 12 Biology Chapter 7
NCERT Solutions for Class 12 Biology Chapter 7 – Evolution covers all the topics and subtopics of this chapter. Some significant topics and subtopics discussed here are mentioned as follows.
- Evolution and Darwin’s theory
This section says that the earth contains numerous life forms, and their study and changes over time are called evolution. Biologists study genetic changes. Charles Darwin is the very famous name of an English biologist. He proposed ‘Darwin’s theory of natural selection.’ He also wrote a book named “Origin of Species by Natural Selection.” You will also learn about Darwin, who believed that all organisms reproduce but not at the same rate. He also cited that every creature is different in some way. Parents transmit some characteristics to their offspring.
- Some important evolutionary ideas
In this part of NCERT Class 12 Biology Chapter 7 You will get a detailed idea of several theories to make you understand about the earliest cellular life forms that appeared on earth 3.4 billion years ago. It further educates you about the development of a single invertebrate cell and multi-cell organisms that happened later.
Here you will also learn that creatures developed in the water and shifted to the land. Gradually, amphibians and reptiles evolved. Maybe 23 million years ago, the primates evolved, and they resembled modern chimpanzees. Perhaps 75000 years modern homo sapiens developed.
- Evidence in support of evolution
This section of the chapter talks about the evidence that supports evolution. Some of them have been given below.
- Fossils, rocks, and sediments indicate the carbon dating of paleontological evidence referring to various periods of history.
- Ernst Haeckel proposed, but Karl Ernst von Baer disagreed about embryo characteristics in the vertebrates that do not match the adults.
- Adaptation shows that creatures with the same structure developed differently according to situations. Convergent evolution shows different structures evolving towards the same function, like flippers in penguins and dolphins.
- Mixed populations survive better and increase their populations, avoiding extinction.
- Adaptive Radiation
Class 12 Biology Evolution explains that certain species like the Australian marsupials and Darwin’s finches evolved in particular geographical areas and spread out to other areas. Natural selection is the result of the inherited ability to adapt to a challenging environment.
- Hardy-Weinberg theory
This section talks about Hardy-Weinberg theory. It tells you that gene pool and allele frequencies in a population remain stable and constant across generations. This is called genetic equilibrium where the sum total of all allelic frequencies is 1. Certain factors that affect this approach are gene flow and genetic drift, genetic recombination, genetic mutation, and natural selection.
- Antibiotic Resistance
This part of NCERT Class 12 Biology Chapter 7 explains Darwin’s theory. As per Darwin’s theory, the environment selects the species that are suited for survival. When antibiotics are used against bacteria, sensitive bacteria die. Some bacteria with favourable mutations survive and thrive. They transfer the genes to other bacteria, too, resulting in antibiotic resistance.
- Components of human evolution
This section considerably explains how interesting research on human evolution has studied the changing brain size and body posture, diets, and characteristics through the ages and how these are altered. Considering the example of the most modern Homo sapiens, the brain size is 1200 cm3 to 1600 cm3. They are entirely erect in posture and 1.5m – 1.8m tall. Following omnivorous food habits, they possess a high intelligence quotient. Their language, speech, culture, art, and language are refined and developed. They cultivate crops and domesticate animals.
CBSE NCERT Class 12 Biology Chapter 7 Exercise
NCERT Solutions for Class 12 Biology Chapter 7 – Evolution comprises answers to all 10 comprehensive questions of the exercise given at the end of the chapter. They cover all the crucial concepts completely. This exercise comprises short answer questions, long answer questions, definition based questions, direct questions, diagrammatic questions, and various other types of questions. The brief of the exercise has been given below.
- Question 1 needs you to explain about the antibiotic resistance in bacteria with the help of Darwinian selection theory.
- Question 2 covers the new fossil discoveries or controversies regarding evolution.
- Question 3 needs you to give the definition of species.
- Questions 4 is based on the various components of evolution.
- Question 5 teaches about the animals other than the man that has self-consciousness
- Questions 6 asks you to mention ten animal names and their fossil name.
- Question7 asks you to practice drawing of animals and plants
- Question 8 & 9 covers adaptive evolution
- Question 10 covers the evolutionary stages of an animal.
Benefits of CBSE NCERT Class 12 Biology Chapter 7 Solutions
Some of the key benefits of learning and revising from NCERT Solutions for Chapter 7 – Evolution are listed below.
- They make learning fun, interesting, engaging, interactive, and efficient.
- They make learning a more natural, enjoyable, stimulating and happy process.
- You can learn anywhere anytime from our NCERT Solutions.
- Our NCERT Solutions have been drafted by our expert Biology teachers who are highly qualified and have years of teaching experience.
- They help you build a strong conceptual foundation and prepare well for various competitive exams.
- They answer all questions from all exercises in a step by step manner.
- They cover a wide range of question types important from exam point of view
- Our NCERT Solutions have been designed to help you learn and revise quickly and efficiently during your board exams.