Biology for IGCSE & O level - Variation And Selection (Section 4)
1
Which of the following is a key characteristic of continuous variation?
Answer(C)
It shows a range of values.
2
What is an example of an adaptive feature for plants in deserts?
3
What is an adaptive feature?
Answer(B)
A feature that helps an organism survive and reproduce in its environment.
4
Which of the following is NOT a key component for natural selection to occur?
5
What is the importance of mutation in the process of evolution?
Answer(B)
It provides the raw material for natural selection to act on.
6
What is the role of mutation in evolution?
Answer(B)
To provide the raw material for evolution.
7
What is the primary role of mutation in natural selection?
Answer(B)
To provide the raw material (genetic variation) for natural selection to act upon.
8
Which of the following is an example of a mutation?
Answer(C)
A change in the DNA sequence
9
What is the relationship between mutation, variation, and natural selection?
Answer(A)
Mutation leads to variation, which is then selected for (or against) by natural selection.
10
Which type of variation is primarily influenced by environmental factors and genes?
11
What is the significance of mutations in the process of evolution?
Answer(B)
They are the source of new genetic variation.
12
In the context of the bird pollination example, what specific adaptation did the Rat's Tail plant develop to aid in pollination?
13
Which of the following is the primary cause of variation in a population?
Answer(B)
Sexual reproduction and mutation.
14
Which of the following is true regarding the white mouse appearing in a wild population of mice?
Answer(D)
This is caused by mutation.
15
Based on the provided text on tomcod fish, what is an example of the result of the natural selection?
Answer(B)
The fish developing resistance to PCBs.
16
Which of the following is an example of an environmental factor that can influence variation?
Answer(B)
Height influenced by nutrition
17
Answer(C)
The enhanced vigor of offspring resulting from outbreeding.
18
Which of the following is an example of a trait that is likely to be improved through selective breeding?
Answer(C)
The yield of grain in a crop.
19
What is the difference between phenotype and genotype?
Answer(B)
Phenotype is the observable characteristics, and genotype is the genetic makeup.
20
Which of the following factors can cause variation within a population?
21
In the context of weed seed dispersal, what is the selective advantage conferred by having heavier seeds?
Answer(D)
They have a greater chance of successful germination and growth.
22
What is a key condition for natural selection to occur?
23
What is the role of the environment in natural selection?
Answer(B)
To determine which variations are beneficial.
24
What is a key feature improved by breeders in cereal crops?
25
Which of the following is the best definition of adaptation in the context of natural selection?
Answer(B)
The process by which populations become better suited to their environment over generations.
26
How do mutations contribute to the process of natural selection?
Answer(C)
By creating new alleles, providing variation.
27
Which of the following is a defining characteristic of outbreeding?
Answer(C)
Breeding unrelated individuals to combine good traits.
28
What is the main goal of selective breeding?
Answer(B)
To produce organisms with desirable traits.
29
What type of variation is the length of the shells of limpets?
30
What is the best example of a human characteristic which shows continuous variation?
31
Which of the following best describes discontinuous variation?
Answer(C)
Characteristics that show distinct, separate categories.
32
Which of the following is the definition of the term gene mutation?
Answer(B)
A change in the DNA base sequence of a gene.
33
What is the role of inheritance in the process of natural selection?
Answer(C)
To pass on advantageous traits to the next generation.
34
What will most likely result from a decrease in the number of antibiotics that are available?
Answer(D)
Many bacteria are resistant to some antibiotics.
35
Which of the following are involved in the process of natural selection?
36
Which of the following is a cause of genetic variation?
37
What is a potential risk associated with inbreeding in selective breeding programs?
Answer(B)
A reduction in genetic variation.
38
How does the process of artificial selection differ from natural selection?
Answer(D)
Artificial selection is driven by human choice, while natural selection is driven by environmental pressures.
39
What is the role of the 'struggle for existence' in natural selection?
Answer(D)
To drive competition and select for advantageous traits.
40
What is the meaning of the 'struggle for existence' in the context of natural selection?
Answer(B)
Competition for limited resources.
41
Which of the following is a defining characteristic of artificial selection?
Answer(C)
It involves human intervention in choosing which organisms reproduce.
42
In a stable environment, what will likely happen to a population over time?
Answer(B)
The population will remain relatively stable.
43
Why are the spines on cacti considered an adaptive feature?
Answer(B)
They protect the cactus from herbivores, reducing water loss and increasing the likelihood of survival.
44
What is the relationship between natural selection and the environment?
Answer(B)
The environment selects for traits that increase survival.
45
What does natural selection act upon?
Answer(B)
Populations of organisms.
46
Which of the following contribute to the success of artificial selection?
47
What is a key factor in competition for resources within a population?
48
What are the key ingredients for evolution to occur?
49
What is the relationship between genes, environment and an organism's traits?
Answer(C)
Traits are always a result of both genes and the environment.
50
What is the significance of variation within a population for natural selection to occur?
Answer(A)
It creates an opportunity for environmental factors to select against certain traits.
