IGCSE Biology Paper-1: Specimen Questions with Answers 159 - 160 of 208

Question 159

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Question

MCQ▾

Three alleles namely IA, IB and IO control the blood grouping in human beings. How many different genotypes are likely to be present in the human population?

Choices

Choice (4)
a.4
b.6
c.5
d.2

Answer

b.

Explanation

Blood Groups in Humans

Blood Groups in Humans

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Question 160

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Question

MCQ▾

The dots represents molecule of a gas in four different containers at the beginning of an experiment.

In which container will more molecules move from P to Q than in the opposite direction?

Four Different Containers

Four Different Containers

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Choices

Choice (4)
a.C
b.B
c.A
d.D

Answer

d.

Explanation

  • Diffusion is the movement of a substance from an area of high concentration to an area of low concentration. Diffusion happens in liquids and gases because their particles move randomly from place to place. Diffusion is an important process for living things; it is how substances move in and out of cells. Diffusion is an important part of many biological and chemical processes. In biological systems, diffusion occurs at every moment, across membranes in every cell as well as through the body.
  • For example, oxygen is at a higher concentration inside arteries and arterioles, when compared with the oxygen levels in actively respiring cells. By the time blood flows into capillaries in the muscle or liver, for instance, there is only a single layer of cells separating this oxygen from hepatocytes or skeletal muscle fiber. Through a process of passive diffusion, without the active involvement of any other molecule oxygen passes through the capillary membrane and enters cells.
The Time Blood Flows into Capillaries

The Time Blood Flows into Capillaries

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