Chapter 8: Genes and Proteins

Question 1

_______ - is a sequence of nucleotides that codes for a specific sequence of amino acids in a protein . Located on DNA strands.

Answer 1

gene

Question 2

State if True or False:

A single DNA molecule contains many genes and a human cell may contain tens of thousands of genes. This means that each cell is capable of producing thousands of proteins.

Answer 2

True

Question 3

Do we need that many proteins in each cell?

Answer 3

Yes

The proteins in turn determine the physical and chemical characteristics of cells and therefore, of the organisms formed from them. Some proteins help assemble
cellular structures such as the plasma membrane, the cytoskeleton, and other organelles.

Question 4

___________ - line up on a specific order/sequence on a gene, therefore, specifying a particular amino acid sequence on the polypeptide chain. To code for one amino acid, 3 nucleotides are required.

Answer 4

“triplet code”.

Question 5

These are specific “triplet codes” that signal the END of a genetic message (end of sequence of amino acids.

Answer 5

“Termination Codes”

Question 6

messenger RNA ( mRNA) is copied from one half of a DNA strand. A complementary strand (of RNA) is formed from a DNA strand. This process is called:

Answer 6

transcription

Question 7

__________ - Transcription of the DNA strand ends at another special nucleotide sequence which specifies the end of the gene.

Answer 7

terminator

Question 8

_____________ - A specific sequence of nucleotides on the DNA strand which is located at the beginning of the gene. It marks the beginning of transcription. Is recognized by RNA polymerase which binds to it. The binding attitudes the enzyme.

Answer 8

Promoter Region

Question 9

• Recognizes and binds to the promoter region and proceeds to separate the two strands of DNA.

Answer 9

RNA Polymerase

Question 10

The transcript includes information from both introns and exons and is called:

Answer 10

pre-mRNA

Question 11

________ - Portions of mRNA that code for amino acids.

Answer 11

Exons

Question 12

________ - mRNA Portions that do not code for any amino acids.

Answer 12

Introns

Question 13

________ - are formed in the nucleolus. _______ is formed from a DNA template.

Answer 13

ribosomes

rRNA

Question 14

In this process, the nucleotide sequence in an mRNA molecule specifies the amino acid sequence of a protein.

Answer 14

Translation

Question 15

__________ - A special tRNA binds to the start codon (AUG) on mRNA, where translation begins.

Answer 15

initiator tRNA

Question 16

_________ - is always the first amino acid in a growing polypeptide.

Answer 16

methionine

Question 17

__________ - are being produced by a “sliding fashion”, they are connected by peptide bond.

Answer 17

amino acids