The Type O blood group is commonly called as universal donor because any blood group can receive the O blood group. The blood group O has no antigen. Due to the absence of antigen it doesn't agglutinate when come in contact with other blood groups in the plasma.
The agglutination reaction happens when opposite antigen and antibody reacts with each other. e.g.- Blood group A contains antigen A and antibody b and the blood group B contains antigen B and antibody a. Agglutination reaction occurs when the antigen A reacts with antibody a. As O blood group has no antigen, agglutination reaction doesn't occur.
By the ligand receptors on the surface of the cell membrane. How do transport proteins make it easier for certain molecules to diffuse across a membrane.
the binding of a signaling molecule, or ligand, to its receiving molecule, or receptor.
Answer:
SARS- CoV- 2 is a virus that infects human by the oral-respiratory way in which the virus enters the body and these viruses have spikes on their surface made of spike proteins that allow these viruses to bind with the infected cell.
The infected cells have ACE2 receptor that is protein present on the surface of the human cells. Binding allows the structural change in the virus to fuse and enter in the cell where viruses reproduce them selves with the cell with cell system.
Answer;
-Hot desert biome
Explanation;
Hot Desert is characterized by very little rainfall or a lot of rain in a very short period. The soils are often salty because minerals do not get washed away. Thus, the climate is characterized by a very little precipitation.
-Plant adaptations: There are few plant species. these plants are adapted to resist drought and store water. For example; Spiny cacti that have thick, fleshy stems that conserve water are common. Their roots extend metres away from the plant to absorb water. Other plants have small, thick, waxy leaves that also store water. Many plants have spines or produce chemicals that protect them from being eaten.
