Answer:
The humans use this limb to grab things, body language, and sign language.
The dogs use this limb for all kinds of weight-bearing activities like walking, jumping, running et cetera.
Birds use this to fly and whales use it as flapper.
The limbs of all these four animals are the example of homologous organs that is, they all are similar in structure but adapted to perform different functions during the course of evolution.
For example, in all four organisms, the limb is made up of the same set of bones such as humerus, radius, ulna, carpals, metacarpals, and phalanges.
Homology in structure shows that they must have evolved from a common ancestor and diverge to perform different functions as an adaptation to the contrasting environment.
Answer:
A. whether the glycoproteins or capsid proteins on its surface recognize those of the host cells.
Explanation:
Virus has different surface proteins that are recognized by the receptors present on its host cell. The range of a virus is determined by the recognition of these proteins by the host cell.
The interaction between the receptor on the host cell and surface proteins on the viral capsid is important for viral genome entry in the host cell and to determine the range of the host cells.
If the surface protein of the virus is not able to bind to the receptor on any cell then the virus can not infect the cell. For example, the HIV virus infects only those cell which have CD4 receptors. So the right answer is A.
The first heart chamber that the dye would enter is right atrium.
This will be followed by
left ventricle
right ventricle
left atrium
coronary valve
Answer:
I. High concentrations of dissolved ions in seawater.
II. Capacity of living organisms to store many types of molecules in solution in their cells.
III. Easy transport of toxic substances through the environment.
Explanation:
This statement is true for all of the following statements given.
<span>Red blood cells normally have a biconcave shape (picture a donut, but instead of a hole through the centre there's just a downward slope to the centre of the cell). If the cell takes on water, it will increase in size and the sloped areas will start to flatten out. If the cell loses water, it will begin to shrivel. Use these observations and your understanding of osmosis to answer the question!</span>
