Variation and selection — IGCSE Biology (0970) questions by topic

Humans produce two types of ear wax, either wet or dry. Which row describes the variation in human ear wax? type of variation controlled by --- --- --- A continuous genes and…

Giraffes are mammals that have long necks. This enables them to eat leaves from tall trees. One theory to explain how giraffes developed long necks is natural selection. Which…

Alpine plants grow on mountains at high altitude. Alpine plants can only grow for a few months because they are covered in snow for most of the year. What are most likely to be…

The diagram shows a sperm cell with a long tail on the left, a midpiece, and a rounded head on the right. Four parts are labelled: A points to the tail, B points to the…

Which characteristic is an example of continuous variation? A ABO blood groups in humans B body mass in cats C seed colour in pea plants D seed shape in pea plants

The photograph shows the butterfly Caligo martia. The butterfly has large patterned wings; the lower (hind) wings each bear a large round dark spot resembling an eye. Which…

The table shows some features of leaves. Which leaf is adapted to survive in hot, dry habitats? number of stomata thickness of waxy cuticle surface area of leaf --- --- --- --- A…

Which row correctly describes a type of selection? type of selection humans involved example --- --- --- --- A artificial no production of farmed animals that produce lots of milk…

Clostridium difficile is a species of bacterium that is resistant to many antibiotics. From 2002 to 2006, the number of people in one country infected with Clostridium difficile…

What is a way in which new alleles are formed? A artificial selection B mutation C natural selection D sexual reproduction

How does artificial selection differ from natural selection? A Artificial selection changes the characteristics of living things. B Artificial selection is based on genetic…

Which diagram of a xerophyte is labelled correctly? Each option shows a cactus-like plant with two labels. The correct labels for a xerophyte are 'waxy layer to stop water…

Organisms can be classified by their features and by studying the sequence of bases in their DNA. Fig. 5.1 is a diagram (an evolutionary tree) showing the evolutionary…

Xerophytes are plants that show adaptive features for dry habitats. Complete the sentence to define the term adaptive feature. An adaptive feature is an ............ feature that…

Many mammals have coloured fur and many birds have coloured feathers. Which uses of colour could help males survive long enough to pass on their features to their offspring? The…

The list shows statements about selection. 1 Individuals reproduce and pass on their alleles to the next generation. 2 Genetic variation exists between individuals and many…

The graph shows how the percentage effectiveness of antibiotic F against MRSA bacteria varied between 1980 and 2000. What is a correct conclusion from the graph? A Antibiotic F…

The images show four animals: 1 sheep, 2 eagle, 3 tortoise, 4 tiger. Which two animals show adaptive features for being secondary consumers? A 1 and 3 B 1 and 4 C 2 and 3 D 2 and 4

Which statement about antibiotics is correct? A Antibiotics do not affect bacteria but kill viruses. B Antibiotics do not affect bacteria or viruses. C Antibiotics kill bacteria…

The photograph shows a species of fish called a leafy sea-dragon. Leafy sea-dragons live in areas of the sea where seaweed is present. Which statements explain how natural…

Which statement about antibiotics is correct? A Antibiotics are used to treat all transmissible diseases. B Antibiotics are used to treat diseases caused by viruses. C Antibiotic…

Fusarium wilt is a fungal disease of bananas that can spread quickly. The table shows the area affected (hectares) over time: 1967 → 0; 1970 → 100; 1976 → 1200; 1983 → 1500; 1999…

Which statement describes a type of variation? A Continuous variation is usually caused by the environment only. B Continuous variation results in a limited range of phenotypes…

The photograph shows a water lily plant, which is a hydrophyte. Which statement explains why the stomata are located on the upper surface of the leaf? A to allow carbon dioxide…

Which term is used when humans cross individuals with desirable features? A genetic breeding B natural breeding C pure-breeding D selective breeding

What is a description of an adaptive feature?

Bacteria such as MRSA are resistant to antibiotics. These processes can occur in bacteria. 1 artificial selection 2 genetic variation 3 mutation 4 natural selection Which…

Which term is a genetic change? A allele B genotype C mutation D phenotype

Which definition of continuous variation is correct? A variation that results in a limited number of phenotypes between two extremes B variation that results in a limited number…

What is a correct statement about antibiotics? A Bacteria may become resistant to antibiotics as a result of artificial selection. B Bacteria may become resistant to antibiotics…

Which term is a genetic change? A allele B genotype C mutation D phenotype

Which adaptation may be present in a xerophyte? A leaves with small surface area and large numbers of stomata B little or no xylem tissue and leaves with large surface area C…

Which types of variation can be inherited? The table considers variation caused by genes and variation caused by the environment (key: shaded = yes, blank = no). A B C D

Which feature is a leaf adaptation for living in a hot, dry desert? A hairy B large surface area C many stomata D thin waxy cuticle

A farmer wanted to use selective breeding to produce goats with a high milk yield. Fig. 7.1 shows a goat being milked. Describe the stages in selective breeding to develop goats…

Antibiotic resistance is an increasing problem worldwide. Erythromycin is an antibiotic. Fig. 3.1 shows the daily doses of erythromycin per 1000 people over a 13-year period…

Some phenotypes are listed. 1 blood group 2 body mass 3 height 4 seed colour in peas Which phenotypes are examples of continuous variation? A 1, 2 and 3 B 2 and 3 only C 2 and 4 D…

What are sources of genetic variation in populations? 1 meiosis 2 random mating 3 random fertilisation A 1, 2 and 3 B 1 and 2 only C 1 and 3 only D 2 and 3 only

Which row shows features of xerophytes that reduce water loss? The table considers green colour from chlorophyll, leaves reduced to spines, presence of stomata and thick cuticle…

Fig. 2.1 is a photograph of some leaves of a water lily, which is a hydrophyte. The water lily has adaptive features that are found in many different hydrophytes. Describe what is…