Speciation

Q.

What is the main difference between character and trait in genetics?

Q. What is Geographical Isolation? Give examples.

Q.

What are the four principles of natural selection?

Q.

Write the factors which could lead to the rise of a new species.

Q.

Definition of Geographical and reproductive isolation

Q. The process by which new species develop from the existing species is called _______.

1. evolution
2. variation
3. selection
4. speciation

Q.

What is the difference between evolution and speciation?

Q. Match the following columns and choose the correct option.
$\begin{array}{cc}ColumnI& ColumnII\\ \text{(a) Mutation breeding}& \text{1. Laborious and expensive}\\ & \text{process to obtain gene}\\ & \text{variation}\\ \text{(b) Selection}& \text{2. Hybrid vigour can be}\\ & \text{maintained for several}\\ & \text{generations}\\ \text{(c) Hybridisation}& \text{3. Simplest and easiest}\\ & \text{method of plant}\\ & \text{improvement}\\ \text{(d) Introduction}& \text{4. Oldest breeding method}\\ & \text{5. Quick method to obtain gene variation}\end{array}$

1. $\begin{array}{ccccc}& A& B& C& D\\ \left(a\right)& 5& 4& 1& 2\end{array}$
2. $\begin{array}{ccccc}& A& B& C& D\\ \left(b\right)& 5& 4& 1& 3\end{array}$
3. $\begin{array}{ccccc}& A& B& C& D\\ \left(c\right)& 4& 2& 3& 1\end{array}$
4. $\begin{array}{ccccc}& A& B& C& D\\ \left(d\right)& 1& 2& 4& 5\end{array}$

Q. Formation of new and distinct species during the course of evolution is an example of .

1. speciation
2. selection
3. variation
4. extinction

Q.

Will geographical isolation be a major factor in the speciation of self pollinating plant species justify your answer?

Q.

Which of the following statements is not true with respect to variation?

1. All variations in a species have an equal chance of survival

2. Change in genetic composition results in variation

3. Selection of variants by environmental factors forms the basis of evolutionary processes

4. Variation is minimum in asexual reproduction

Q. Charles Darwin was the first scientist to propose the theory of evolution.

1. False
2. True

Q.

Does geographical isolation of individuals of a species lead to the formation of a new species ? Provide a suitable explanation for your answer.

Q.

New species may be formed if :
(i) DNA undergoes significant changes in germ cells
(ii) chromosome number changes In the gamete
(iii) there is no change in the genetic material
(iv) mating does not take place
(a) (i) and (ii)
(b) (i) and (iii)
(c) (ii), (iii) and (iv)
(d) (i), (ii) and (iii)

Q.

A species may be reproductively isolated through which of the following causes?

1. ecology

2. anatomy

3. behaviour

4. all of the above

Q.

Name the ancestor of the following :
Broccoli, Kohlrabi, Kale

Q.

How did Darwin explain the origin of new species on earth?

Q.

The diagram below illustrates the change that occurred in the frequency of phenotypes in an insect population over 10 generations. A probable explanation for this change would be that over time there was…….

1. an increase in the adaptive value of gene a

2. a decrease in the adaptive value of gene a

3. a decrease in the mutation rate of gene A

4. an increase in the population of this insect

Q.

What is the Phenetic species concept?

Q.

What factors contribute to adaptive radiation?

Q.

(a) What is meant by a species? Give two examples of plant species and two of animals.
(b) State the various factors which could lead to the formation of new species.

Q.

The study of the formation, growth and development of a new individual from an egg is called __________.

1. embryology

2. heredity

3. cytology

4. genetics

Q.

Question 10
New species may be formed if

(i) DNA undergoes significant changes in germ cells.
(ii) Chromosome number changes in the gamete.
(iii) There is no change in the genetic material.
(iv) Mating does not take place.

(a) (i) and (ii)
(b) (i) and (iii)
(c) (ii), (iii) and (iv)
(d) (i), (ii) and (iii)

Q.

Genetic drift is an account of ………………………

1. increase in population

2. variations

3. mutations

4. abrupt decrease in population

Q.

Give one example for each of the following.
(a) Amphibious plant.
(b) Symbiotic plant
(c) Colonial coelenterate

Q.

Bacteria have a simpler body plan when compared with human beings. Does it mean that human beings are more evolved than bacteria? Explain your answer?

Q.

What name is given to the sequence of gradual changes over millions of years in which new species are produced?

Q. Why is variation beneficial to the organism but not necessary for the individual

Q. Why does Sympatric Speciation occurs?

Q.

What is the smallest category of biological classification?