In my guess try A. hope I tried my best if I’m wrong I am sorry for answering not correctly
<em><u>Answer</u></em>
<em><u>about 3.9 billion years ago</u></em>
<em><u>about 3.9 billion years agoThe most recent common ancestor of all currently living organisms is the last universal ancestor, which lived about 3.9 billion years ago.</u></em>
Answer:
The body naturally responds by rejecting the new organ because it is identified as a foreign object. Doctors use tissue typing to measure the compatibility of the antigens in the organ to that of the recipient. Another way doctors make sure the organs are accepted is through immunosuppressants that make the immune system does not attack the organ.
Explanation:
must include:
body rejects transplants because it recognizes them as foreign
lymphocytes attack the new organ
tissue typing measures antigens on tissue donor organ for compatibility
immunosuppressants disrupt the replication process of lymphocytes that produce antibodies and makes the immune system less effective
Answer:
The answer is double helix.
Explanation:
In its natural state, each DNA molecule is actually composed of two single strands held together along their length with hydrogen bonds between the bases. Watson and Crick proposed that the DNA is made up of two strands that are twisted around each other to form a right-handed helix, called a double helix.
Hope this helps!! ;)
Answer:
False, all plants cells have cell membrane, in addition most of them have also cell wall. They have both
