2. The original DNA is ATT-TGA-GCC. The mutated DNA is ATT-GAG-CC.
The example above is an example of a(n)
deletion
insertion
substitution
duplication

deletion

Explanation:

there is one less base pair, the third T of the original DNA was deleted

the level of progesterone is low at the pre-ovulatory phase of the cycle but it gradually increases and the levels are high at the luteal phase. if pregnancy occurs, the level of progesterone will be high throughout the pregnancy.

if egg is fertilized and the mother gets pregnant, progesterone starts preparing the uterus for the implantation. it starts building up the lining of uterus and make it hostile of the period of pregnancy.

a symbiotic relationship with the mitochondria