Extra Questions and Answers for CBSE Class 10 Science Chapter 9 - Heredity and Evolution are available here for free PDF download. All these extra questions are entirely based on the NCERT textbook. These questions are quite helpful to revise all the key concepts and important terms in a short time before the exam. Therefore, students should practice with these extra questions to prepare well for their upcoming CBSE Class 10 Science Exam 2021 and secure high marks.
CBSE Class 10 Science Extra Questions and Answers for Chapter 9 - Heredity and Evolution:
Q. What is the unit of inheritance in living organisms?
Gene is the unit of inheritance in living organisms.
Q. Which features of fossils are used for study of evolution?
Following three features of fossils are used for study of evolution:
(a) Fossils represent modes of preservation of ancient species.
(b) Fossils help in establishing evolutionary traits among organisms and their ancestors.
(c) Fossils help in establishing the time period in which organisms lived.
Q. Which chromosomes are called autosomes?
Human beings have 23 pairs of chromosomes out of which first 22 pairs are similar in males and females. These similar chromosomes are called autosomes.
Q. What happens if DNA copying is not perfectly accurate?
If the DNA copying is not perfectly accurate it will produce variation in the reproduction process.
Q. Why is DNA copying necessary during reproduction?
DNA copying is necessary during reproduction as DNA carries genetic information. Therefore, for an organism to produce similar offsprings it is necessary to copy DNA.
Q. What do you mean by the term speciation?
The process by which new, distinct species develop from the existing species due to genetic, behavioural or physical isolation is known as speciation.
Q. What do you mean by dominant traits?
The trait that gets expressed in the offspring by taking over the other inherited trait is named as dominant trait.
Q. What do you mean by recessive traits?
The trait that remains hidden and is dominated by the dominant trait is named as recessive trait.
You may also download all the above questions and answers in PDF from the link mentioned below:
While making the exam preparations, students should go through the Revised CBSE Syllabus for Class 10 Science so that they can avoid the deleted topics and prepare according to the topics that are prescribed by the board.