Answer:
A
Explanation:
The DNA is made 4 nitrogenous bases. A (adenine) pairs with T (thymine) and are held by two hydrogen bonds. C (cytosine) pairs with G (guanine) and are held by three hydrogen bonds.
You might wanna remember this by the preposition 'at', which ultimately makes C and G together. Or you might wanna remember it by something like G- C<em>AT</em>.
Answer:
It has 4 trophic levels.
Explanation:
The first level would be the producers, followed by the primary consumers, then the secondary consumers, then the tertiary comsumers.
/ Tertiary consumers \
/ Secondary Consumers \
/ Primary Consumers \
/ Producers \
/________________________________\
The answer is <span>-Only the few bacteria that were immune to the antibiotic survived and reproduced, making all their offspring immune to it as well.
Bacteria (or any other organism) are not able to make changes to their DNA in order to protect themselves or to learn to remove the receptors on their cell surfaces. If they were able to produce toxins against the antibiotics, they would all survive.
These leave the second choice as the correct answer. This is the real situation, and is a good example of natural selection.</span>
Alleles in the F1 must be Tt to have height variety in the F2.