2208-BIOL-1345-002 Exam 3 - Requires Respondus Lockdown Browser+ Webcam

What is a gamete? A. An egg or sperm cell B. Nearly an cell in the body Except those that produce sperm of egg cells C. A prokaryotic organism D. A fertilized egg cell

A. An egg of sperm cell

In transcription there is/are ____ template strands(s). The enzyme _________ builds the transcript by adding nucleotides to the_______ end of the growing strand A. 1, RNA polymerase,3' B. 1, DNA polymerase, 3' C. 2, primate , 5' D. 1, Ligase, 5'

Answer: 1, RNA polymerase, 3'

What is meant by the description " Antiparallel" regarding the strands that make up DNA? A. One strand runs in the 5' to 3' direction, while the other stand runs in the 3' to 5' direction B. The twisting nature of DNA creates strands that wind around each other instead of lying flat. C. One strand contains only purines and the other contains only pyrimidines D. One strand is positively charged and the other is negatively charged

Answer: A. One strand runs in the 5' to 3' direction, while the other strand runs in the 3' to 5' direction

A group of offspring displaying an approximately 3:1 phenotypic ratio for 2 particular traits of a character indicates ? A. That the parents were both heteroszygous for alleles controlling the traits B. That the the parents were true-breeding for different traits C. The blending inheritance of traits has occurred D.that each offspring has the alleles for each of the traits

Answer: A. That the parents were both heterozygous for alleles controlling the traits

Considering both strands, cytosine makes up for 42% of the nucleotides in a sequence of DNA from an organism. Approximately what percentage of the nucleotides in this sample will be thymine ? A.8% B.16% C.42% D.31%

Answer: A.8%

Mitosis results in the production of ____ cells that are ____ , and meiosis results in the production of _______ cells are _____________ A. 2, haploid/4 , diploid B. 2,/diploid/4, haploid C. 4,diploid/2, haploid D. 4, haploid/ 2 , diploid

Answer: B. 2, diploid/ 4, haploid

A sexually reproducing animal has two unlinked genes , one for head shape ( H ) and one for tail length ( T ) . Its genotype is HhTtWhich of the following allelic combinations below is possible in a gamete from this organism ? A. Hh B.Ht C. tt D. HhTt

Answer: B. HT

The spindle fibers in mitosis and meiosis are A. DNA strands B. Microtubules C. Molecules of cellulose D. RNA strands

Answer: B. Microtubules

Chromosomes condense in meiosis during A. Separation of homologues B. Prophase 1 C. Meiosis 2 D. Anaphase 2

Answer: B. Prophase 1

A cell after the end of meiosis 2 and cytokinesis can be described as ? A. Having one fourth the chromosomes of the original parent cell B. Having one half of the chromosomes and one half the DNA of the original cell C. Having an identical number of chromosomes as the original parent cell D. having an identical DNA contents as the original parent cell

Answer: B. having one-half the chromosomes and one-half the DNA of tye original parent cell

At what codon position would a point substitution in a protein-coding gene be least likely to be harmful ? A. Fourth B. Third C.first D. Second

Answer: B.Third

If you cross AaBbDd X AaBbDd, what is the probability of obtaining the genotype aabbdd? A. 1/16 B.1/8 C. 1/64 D.1/2

Answer: C. 1/64

A particular triplet of bases in the template strand of DNA is 5' AGT 3'. The corresponding codon for the mRNA transcribed is? A. 3'ACU 5' B. 5'UCA 3' C. 3'UCA 5' D. 5' TCA 3'

Answer: C. 3'UCA 5'

What enzyme catalyzes( facilitates) the joining of DNA fragments during replication A. DNA polymerase B. RNA polymerase C. Ligase D. Topoisomerase

Answer: C. Ligase

If 2 alleles of a gene are codominant, and an individual that is homozygous for one allele is crossed with an individual that is homozygous for the other A. Two cancel each other out , and there is no phenotype in the offspring B. Epistasis is occurring C. Offspring should show phenotypes with full expression of both alleles D. Offspring should only show phenotypes associated with an allele from the female present

Answer: C. Offspring should show phenotypes with full expression of both alleles

A dominant allele ? A. Is the best allele in a population B. can only show its effect if 2 copies are present C. Show it's effect even if only copy is present D: is the most common allele in a population

Answer: C. shows it's effect even if only one copy is present

In the nuclear genetic code of eukaryotes , how many codons specify start, stop and specific amino acids ? A. 1,3,20 B.3,1,20 C. 3,1,60 D.1,3,61

Answer: D. 1,3,61

Which is the following contains the smallest number of nucleotides? A. Typical eukaryotic mRNA B. Typical eukaryotic chromosome C. Typical eukaryotic genome D. Codon

Answer: D. Codon

Which best describes the ability of a single gene to have multiple phenotypic effects ? A. Epistasis B. Homozygosity C. Complete dominance D. Pleiotropy

Answer: D. Pleiotropy

Large numbers of ribosomes are present in cells that specialize in producing which of the following molecules? A. Nucleic acids B. Cellulose C. Lipids D. Proteins

Answer: D. Proteins

The leading and lagging strand differ that A. The leading strand is synthesized by adding nucleotides to the 5' end of the growing end, and the lagging strand is synthesized by adding nucleotides to the 3' end . B. The leading strand is synthesized by adding nucleotides to the 3' end of the growing strand, and the lagging strand is synthesized by adding nucleotides to the 5' end C. The lagging strand is synthesized continuously , whereas the leading strand is synthesized in short fragments that are ultimately stitched together D. The leading strand is synthesized in the same direction as the movement of the replication fork, and the lagging strand is synthesized in the opposite direction

Answer: D. The leading strand is synthesized in the same direction as the movement of the replication fork and the lagging strand is synthesized in the opposite direction.

A particular triplet of bases in the template strand of DNA is AAA. The anticodon on the tRNA that binds the mRNA codon is A. UUU B.TTT C.GGG D.AAA

Answer: D.AAA

In genetic terms, what is a locus ? A. The place where 2 sister chromatids are joined together B. A genotype C. The place where a gene is found on a chromosome D. An allele of a gene

Answer: The place where a gene is Found on chromosome

The junction between chromatids that allow crossing over in meiosis are called ? A. Kinetchores B. Centromeres C. Chiasmata D. Centrosomes

Answer: chiasmata

Regions of RNA in between the protein-coding sequences in pre-mRNA are called ? A. Exons B. Centrioles C. Promoters D. introns

Answer: exons

Polypeptides are assembled from _____ from ________ monomers. A. Peroxisomes, lipid B. Rough, endoplasmic reticulum, carbohydrate C. Ribosomes, amino acids D. Lysosomes, nucleotide

Answer: ribosomes, amino acids

What is the function of helicase? A. Replacing thymine with uracil B. Joining together individual fragments of DNA C. Unwinding the 2 strands of DNA molecule D. Elongating new DNA at a replication fork by adding nucleotides to the existing chain

Answer: unwinding the 2 strands of DNA molecule

You examine the karyotype of a chromosomally normal human male. You pick out two specific chromosomes: the Y chromosome and a particular copy of autosome 9. What are the chances that this individual received this particular Y chromosome from his father and this particular autosome 9 from his mother? A.0% B.100% C. 25% D.50%

Answer:50%

A sexually reproducing animal has two unlinked genes, one for head shape (H) and one for tail length (T). Its genotype is HhTt. Which of the following genotypes is possible in a gamete from this organism? A.Hh B.HT C.tt D.HhTt

Answer:HT

Huntington's disease is an autosomal dominant disorder . If dad is heterozygous for the disease , while mom is healthy what is the probability that their child will have the disease ? A. 50% B. 25% C.100% D. 0%

Answers: A.50%

Chromosomes condense in meiosis during: A. Separation of homologogues B. Prophase 1 C. Meiosis 2 D. Anaphase 2

Answers: B. Prophase 1

Humans are A. Haploid organisms in which the female is the hetermogametic sex B. Diploid organisms in which the female is the heterogametic sex C. Diploid organism in which the male is the heterogametic sex D. Haploid organism in which the male is the heterogametic sex

Answers: C. Diploid organism IN which the male is the heterogametic sex

Telomerase A. Catalyze formation of the centromeres B. Builds bonds between amino acids C. Prevents chromosomes shortening caused by DNA replication D. Catalyze formation of the spindle fibers

Answers: C. Prevents chromosome shortening caused by DNA replication

If quantative( = polygenic) inheritance is occurring for a traits of character A. The trait is probably not heritable and all phenotypic variation is caused by the environment B. Inheritance of traits is probably based on single gene C. Alleles that once were recessive have become dominant D. There will be a wide range of phenotypes in the population that cannot be assigned to simple, discrete categories

Answers: D. There will be a wide range of phenotypes in the population that cannot be assigned to simple discrete categories

A human cell containing 22 autos ones and Y chromosome is ? A. A zygote B. A somatic C.a sperm D. An egg

C. A sperm