DNA only replicates once in either mitosis or meiosis. I guess you mean how many times a pair of sister chromatids are separated. Still, once for either of them. The only difference between mitosis and meiosis is that mitosis forms 2 identical daughter cells with diploid number of chromosomes in a single 'split'.
Answer:
Contraceptive Education/Availability, Healthcare, Country Development, and Political Climate
Explanation:
When people are educated about proper contraceptive use they can still have sex without the consequence of pregnancy. The availability of contraceptives goes hand in hand with contraceptive education.
Advanced healthcare can help prevent disease through immunizations and further the life expectancy of the country's population. Hand washing can significantly lower the spread of disease.
The lower the development of a country the higher the birth rate is, while the higher the developed countries have a lower birth rate and their life expectancy is much longer.
The political climate of a country can greatly affect the population growth. The more negative the political climate is usually causes a smaller birth rate. For example when China implemented the one child policy their population growth declined;.
The correct answers are:
2) Peptide bonds form from nucleophilic attack by an electron pair on an alpha - amino nitrogen atom on an alpha - carboxyl carbon atom of another amino acid and
4) Peptides are polymers of amino acids.
A peptide bond is an amide type of covalent chemical bond. It is formed between two amino acids: C1 (carbon end) of one alpha-amino acid and N2 (nitrogen end) of another. Peptide bonds are the basis for the formation of a peptide chain and consequently protein. Formation of peptide bond is a condensation process, meaning that when two amino acids combine and link, water molecule is released and dipeptide is a product of that reaction.
Answer:
Phenotypic plasticity
Explanation:
Humans have evolved over thousands of years to adapt to various environmental changes. For example, when we are in an environment that requires certain level of adaptation our off spring often formalizes epigenetic traits that lows them to overcome small changes in the environment. Over time certain genes that are turned on may remain on and eventually the ones that are off remains off. This give rise to some genes that "don't work" after millions of years of such evolution we end up with a complex genome with more DNA than "working genes".
