Question

part 1: genes, proteins, and mutations
directions: fill in the blanks using the word bank. each will only be used once.
inherited\t\t\t\t\t\ttraits\t\t\t\t\t\tdna\t\t\t\t\t\t46\t\t\t\t\t\tproteins
parent\t\t\t\t\t\tgenes\t\t\t\t\t\ttwo\t\t\t\t\t\t23\t\t\t\t\t\talleles
organized\t\t\t\t\t\tnucleus\t\t\t\t\t\thalf\t\t\t\t\t\tchromosomes\t\t\t\t\t\tsegments

1. organisms contain a unique set of __, or genetic coding. this dna is often stored as a highly structure called a . the genetic material is stored in the __ of the cell.
2. organisms get __ their genetic material from each . in humans, this means chromosomes are from each parent for a total of __ chromosomes.
3. dna contains all the __ that will make up an organism. these genes are of the dna code for specific __.
4. proteins determine the __ of an individual. an individual contains variations of each gene which are called __.

directions: answer the following questions.

1. how does dna become a physical trait?
2. what would be affected first by a change in the genetic code?
3. what is a genetic mutation?
4. what factors cause genetic mutations?

Explanation:

Step1: Fill blanks (Passage 1)

Organisms contain a unique set of DNA, or genetic coding. This DNA is often stored as a highly organized structure called a chromosome. The genetic material is stored in the nucleus of the cell.

Step2: Fill blanks (Passage 2)

Organisms get half their genetic material from each parent. In humans, this means 23 chromosomes are inherited from each parent for a total of 46 chromosomes.

Step3: Fill blanks (Passage 3)

DNA contains all the genes that will make up an organism. These genes are segments of the DNA code for specific proteins.

Step4: Fill blanks (Passage 4)

Proteins determine the traits of an individual. An individual contains two variations of each gene which are called alleles.

Step5: Answer question 5

DNA is transcribed into mRNA, which is translated into proteins. These proteins carry out functions that produce physical traits (e.g., enzymes for pigment production, structural proteins for eye shape).

Step6: Answer question 6

A change in the genetic code first affects the structure of the mRNA transcribed from the DNA, which then immediately alters the amino acid sequence of the protein being synthesized.

Step7: Answer question 7

A genetic mutation is a permanent change in the nucleotide sequence of an organism's DNA, which can alter gene function or expression.

Step8: Answer question 8

Genetic mutations can be caused by internal factors (errors in DNA replication, spontaneous chemical changes in DNA) or external factors (exposure to radiation, chemical mutagens, certain viruses).

Answer:

1. DNA; organized; chromosome; nucleus
2. half; parent; 23; inherited; 46
3. genes; segments; proteins
4. traits; two; alleles
5. DNA is transcribed to mRNA, which is translated to proteins; these proteins drive the development of physical traits.
6. The structure of the mRNA and the amino acid sequence of the corresponding protein (the protein being synthesized) are affected first.
7. A permanent change in an organism's DNA nucleotide sequence that may modify gene function.
8. Internal factors (DNA replication errors, spontaneous DNA changes) and external factors (radiation, chemical mutagens, viruses).