Nucleotides are a base pair and they fit together because their shape allows them to bond. The A-T pair frames two hydrogen bonds. G-C forms 3. As the strands bond they hold the Base Pairs of DNA together
Answer:
1) Recursive definition: 
2) At the beginning of the 4th interval
Explanation:
1)
The initial population of the bacteria at time zero is

Here we are told that the reading is taken every two hours; we call this time interval "n", so

And also, after every time interval n, the number of bacteria has tripled.
This means that when n = 1,

And when n=2,

Applied recursively, we get

And substituting p0,
(1)
2)
Here we want to find at the beginning of which interval there are

bacteria.
This means that we can rewrite eq.(1) as

By simplifying,

Which means that

However, this means that the number of bacteria is 1,350,000 after 3 time intervals; therefore, at the beginning of the 4th interval.
Answer:
The endocrine system secretes hormones into blood and other body fluids Hormones provide feedback to the brain to affect neural processing. Reproductive hormones affect the development of the nervous system.
Explanation:
Pioneer species, I think.
Serous membranes line certain cavities within the anterior body cavity. This statement is FALSE.
Serous membrane, also known as serosa in anatomy, is a silky tissue membrane made of mesothelium that lines the interior of bodily cavities and their contents. It secretes serous fluid to permit greased sliding motions between friction surface. Organs housed in body cavities that don't open up to the outside are covered by serous membranes that line the body cavities. The epithelium secretes a thin coating of serous fluid that coats serous membranes.
An indication of a serous membrane is the lining of the thorax. The pleura is the name for the serous membrane found in the thorax. The visceral pleura, the innermost layer, is on the lungs, whereas the parietal pleura, the outermost layer, is on the interior layer of the thorax.
Learn more about Serous membrane
brainly.com/question/12993358
#SPJ4