Answer:b. Facilitated transport
Explanation:in the usual activities of the cell,it's cell membrane is responsible for the movement of substance in and out of the cell.
Such substances include nutrients,water, oxygen etc.
The plasma membrane select the substances that it allows into the cell thus it is said to be selectively permeable.
The plasma membrane of the cell has a phospholipid bilayer made up of cholesterol, proteins and glycoproteins.
The proteins on the membrane are useful for facilitated diffusion.
In this diffusion process,the proteins helps to carry large molecules across the cell membrane.such molecules includes glucose,amino acids etc.
In the process energy is not expended so it is a type of passive transport.
Answer:
2, 3, 4, 1
Explanation:
Inversion of DNA sequences refers to the rearrangement of the sequences where a segment is reversed end to end.
For instance in order for the gene of species to have the sequence STUVWX
The order of evolution will be
- sequence UVXTSW will be the first sequence
When XTSW segment is inverted WSTX
- sequence UVWSTX will be the result of the inversion.
section UVWS is inverted to SWVU
- sequence SWVUTX is formed.
when WVUT undergoes inversion to TUVW
- It becomes the original arrangement of STUVWX .
The biggest challenge is rejection. Sometimes the human body will not accept the pig organ unfortunately.
Hope this helped. Good luck !
<h3><u>Answer;</u></h3>
peptidoglycan
The molecular basis of the Gram stain is the amount of<u> peptidoglycan</u> in the bacterial cell wall.
<h3><u>Explanation</u>;</h3>
- Gram stain is differential stain that is very useful for identifying and classifying bacteria as either gram negative or gram positive.
- Gram negative are those that decolorize easily, such as E. coli, while Gram positive are those that retain the primary stain and do not decolorize easily.
- The result depends on the bacteria cell wall structure, the cell wall of a Gram-negative bacterium is composed of 20 percent or less of peptidoglycan.
