Question

1 multiple choice 2 points how many pairs of sex chromosomes do humans have? 46 23 2 1 2 multiple choice 2 points about how many nucleotide bases make up the human genome? 3 billion 1 trillion 1 billion 30 million 3 multiple choice 2 points a change that alters the base sequence in an organisms dna is called a mutation synapsis replication disjunction

Explanation:

1. Humans have 23 pairs of chromosomes in total, out of which 1 pair is sex - chromosomes. The other 22 pairs are autosomes.
2. The human genome is made up of about 3 billion nucleotide bases.
3. A change in the base - sequence of an organism's DNA is defined as a mutation. Synapsis is the pairing of homologous chromosomes during meiosis, replication is the process of copying DNA, and disjunction is the separation of chromosomes during cell division.

Answer:

1. D. 1
2. A. 3 billion
3. A. mutation