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>.
the main difference is that bacteria are free-living cells that can live inside or outside a body, while viruses are a non-living collection of molecules that need a host to survive.
Many bacteria help us: living in our gut digesting and helping absorption of our food, fixing nitrogen and decomposing organic materials in soil. Similarly, not all viruses are bad—we now know there are also beneficial viruses present in our gut, skin and blood that can kill undesirable bacteria and more dangerous viruses.
A The continents were once joined together
Explanation:
All the continents were once together making a huge one called Pangea.
Mineral X is softer than a diamond.
Answer:
First, the zygote becomes a solid ball of cells. Then it becomes a hollow ball of cells called a blastocyst. Inside the uterus, the blastocyst implants in the wall of the uterus, where it develops into an embryo attached to a placenta and surrounded by fluid-filled membranes.
