Answer:
A point mutation can be described as a mutation in which changes occur in a single nucleotide. A nucleotide may get changed, deleted or inserted from the sequence of DNA. Point mutations can be harmless or harmful depending on the nucleotide in which the changes occur.
A change in just one nucleotide can result in the formation of wrong amino acid and hence changed or wrong proteins can be formed. If the original protein was involved in cellular reproduction, then the entire process of reproduction can be affected by a point mutation.
Sickle- cell anaemia is a disease in which the body fails to produce enough healthy red blood cells. This disease occurs due to point mutation. Point mutation occurs where glutamine (GAG) of the β-globin gets changed into valine (GUG). This change causes the haemoglobin to get a deformed structure due to which it is not able to carry out oxygen.
Answer:
Height is affected by multiple pairs of genes on different chromosomes.
Explanation:
The quantitative traits are those whose inheritance pattern is the result of the action of multiple genes that act together with the environment. The distribution of quantitative traits in the population follows a bell-shaped curve, which is referred to as normal distribution or Gaussian distribution. These traits are 'quantitative' because they vary among individuals in the population to produce a continuous range of phenotypic values. Examples of quantitative traits include, among others, metabolic rate, height, and weight.
Global warming affects the spread of animals because different areas will become suitable for different species, so they spread out. This can cause diseases to spread, as the animals may bring them with them. This can also happen in the opposite direction, where the climate change causes less habitats to be suitable for animals, so they become more sparse
