The fertilized cell that results is referred to as a zygote. A zygote is diploid cell, which means that it has twice the number of chromosomes as a gamete
Answer:
A- A pH change can cause the enzyme to change its shape
Explanation:
A rise or fall in the pH of the medium from the optimum of pH 7 usually affect the enzymes' active sites of and therefore the shape and the rate of enzyme activity.
Assuming the pH is too low, the enzyme medium becomes acidic;Acidosis. The high Hydrogen ions concentration interacts with the R-groups of the amino acids moiety of the enzymes, this interaction affects the ionization of the R-groups, disrupting the ionic bonding holding these R-groups in shape.
This results in loss of the 3-Dimensional shape arrangements of the protein molecule and therefore of the active sites. Since active sites of enzymes determines the specificity of the <u>enzymes substrate- complex </u> to give <u>enzyme-product complex,</u> the catalytic activity of the enzymes decreases, <u>the rate of reaction decreases,and products formation stops, and the reaction also stops.</u>
The same is applicable to extremely high pH=Alkalosis.
However, the effective buffer system of the body prevents this scenarios from happening in real sense in the body. Through mopping by the haemoglobin, excretion by the kidney, etc
<h2>Galapagos Finch </h2>
Explanation:
Darwin's finches are a classical example of an adaptive radiation
- Darwin's finches common ancestor arrived on the Galapagos about two million years ago,during the time that has passed the Darwin's finches have evolved into 15 recognized species differing in body size, beak shape, song and feeding behavior
- Changes in size and form of the beak have enabled different species to utilize different food resources such us insects, seeds, nectar from cactus flowers all driven by Darwinian selection
- From 1831 to 1836, Darwin was part of a survey expedition carried out by the ship HMS Beagle, which included stops in South America, Australia, and the southern tip of Africa
- At each of the stop, Darwin had the opportunity to study the local plants and animals
- Darwin found that nearby islands in the Galapagos had similar but nonidentical species of finches living on them,he noted that each finch species was well-suited for its environment and role
- For example species that ate large seeds tended to have large, tough beaks, while those that ate insects had thin, sharp beaks
- According to Darwin's idea, this pattern would make sense if the Galapagos Islands had long ago been populated by birds from the neighboring mainland
- On each island, the finches might have gradually adapted to local conditions (over many generations and long periods of time)
- This process could have led to the formation of one or more distinct species on each island
- Darwin developed and refined a set of ideas that could explain the patterns he had observed during his voyage
- In his book, On the Origin of Species, Darwin outlined his two key ideas: evolution and natural selection
- Natural selection which also known as “survival of the fittest,” is the more prolific reproduction of individuals with favorable traits that survive environmental change because of those traits; this leads to evolutionary change