Question 1

Match between columns
                        Premises: The mutation in the keratin gene in sphynx cats causes a change in the intron-exon splice site and is an example of which type of mutation?
What type of mutation occurred if the sequence GGACTCCTCCTCAGA is changed to GGACTCCTTCCTCAGA?
If UUA codes for leucine (leu), UUU codes for phenylalanine (phe), AUU codes for isoleucine (iso), AAA codes for asparagine (asn), and UAA codes for a stop codon, which type of mutation would be responsible for changing the protein sequence from leu-phe-iso-iso-stop to leu-phe-leu-phe-asn-stop?
Which type of mutation replaces glutamic acid with valine in beta globin proteins in individuals with sickle-cell anemia?
A deletion in the beta globin gene leads to this type of mutation, causing beta-thalassemia.
What type of mutation is least likely to alter the amino acid sequence?

Accepted Answer

The Answer of i nsertion only and d eletion only is...

Question 2

Match between columns
                        Premises: binds to ribosomes to begin translation
complex with proteins to form ribosomes
occurs when stop codons are read
a tRNA triplet complementary to a mRNA codon
guided and catalyzed by RNA polymerases
RNA-directed synthesis of polypeptide chains
all of the mRNA codons
sites for polypeptide assembly
an mRNA code for one amino acid
site at which RNA polymerase binds and initiates transcription

Accepted Answer

The Answer of genetic code and anticodon and translation termination is...

Question 3

Homeotic genes encode which type of protein?
A) transcription factors
B) ribosomal proteins
C) channel proteins
D) membrane-associated proteins
E) DNA methylases

Accepted Answer

Homeotic genes encode transcription factors that regulate the expression of other genes involved in the development of body segments and organs.

Question 4

Most homeotic genes encode _____; therefore, the protein products of these master genes are found in the _____.
A) stop codons; ribosomes
B) transcription factors; nucleus
C) transcription factors; extracellular matrix
D) splicing proteins; endoplasmic reticulum
E) energy-releasing proteins; mitochondria

Accepted Answer

Homeotic genes encode transcription factors that regulate the expression of other genes, so their protein products are found in the nucleus, where transcription takes place.

Question 5

Female secondary sexual traits, such as functional breasts and fat deposits around the hips and thighs, are determined by _____.
A) the presence of the master gene, SRY
B) increased concentration of gene products from the two X chromosomes
C) absence of gene products from the Y chromosome
D) sex hormones
E) maternal influence

Accepted Answer

Female secondary sexual traits are determined by sex hormones, specifically estrogen and progesterone. The presence or absence of genes from the sex chromosomes (A, B, C) or maternal influence (E) do not directly contribute to the development of these traits. While increased concentration of gene products from two X chromosomes (B) may result in some female-specific traits, it is not the primary determinant for functional breasts and fat deposits around the hips and thighs.

Question 6

Epigenetic modifications _____.
A) are considered evolutionary
B) are completely reset during development
C) alter the DNA sequence
D) can persist for generations
E) respond less rapidly to environmental changes than altering the DNA sequence

Accepted Answer

Epigenetic modifications can persist for generations, without altering the DNA sequence itself.

Quiz 8: Gene Expression and Control

Identify the type of mutation associated with the following questions and statements. Some answers may be used more than once.

Match each term with the most appropriate description.

Homeotic genes encode which type of protein?

Most homeotic genes encode _; therefore, the protein products of these master genes are found in the _.

Female secondary sexual traits, such as functional breasts and fat deposits around the hips and thighs, are determined by _____.

Epigenetic modifications _____.