Answer:
The correct option is option A
Explanation:
Restriction enzymes are endocleases that cleave DNA fragment (<u>of usually four, five or six nucleotide long</u>) at <u>specific sites to produce blunt or sticky ends</u>. They <u>recognize palindromic sequences of host DNA when cleaving the specific sites</u>. The sequences below (on complementary strands) give an example of a palindromic sequences.
5'-CCC║GGG-3'
3'-GGG║CCC-5'
As can be seen above, when read from 5' to 3', the two sequences are the same despite being on opposing strands. And when cut between the guanine (G) and cytosine (C) (as shown above), it produces a blunt end. But when cut as shown below produces a sticky end.
5'- G║AATTC -3'
3'- CTTAA║G -5'
The explanation above shows options C and D are right while option A is wrong (hence the correct option).
Also, bacteria prevent their own DNA from been digested by restriction enzymes by adding methyl group to their restriction sites <u>which prevents restriction enzymes from recognizing restriction sites of their DNA;</u> this generally makes bacterial DNA to be highly methylated. This explanation makes option B right also.
The f° -f^1 complex in the mitochondrial structure helps it
D) cell wall have vesicles and cell membrane have plasmids...
Remember cell wall is hard n have rigid shape and it protect de internal organs... But a membrane is soft n nor a rigid shape...
If an egg sits for 3 days in the water, then in will float becasue of the density of the egg
<span>The correct answer is d. increase the rate of breathing.</span>
<span>
Peripheral chemoreceptors (the carotid and aortic bodies) can sense hypercapnia (high CO2) and then they send a signal to the breathing centre. Breathing centre is in medulla oblongata which regulates breathing movements. When CO2 reaches a certain level, a signal is sent to trigger an inhalation and the rate of breathing is increased.</span>
