Module 2 Exam

Sickle crisis requires immediate medical attention. This medical condition is characterized by_______

-A decrease in gas exchange between the alveoli and the capillaries -anemia -chest pain and shortness of breath

Meiosis is different from mitosis in that meiosis results in

4 haploid daughter cells that are genetically diverse, whereas mitosis results in two diploid daughter cells that are genetically identical

A single mutation cause sickle-cell disease. Which of the following statements best describes how this occurs?

A single nucleotide mutation causes a normal glutamine amino acid to be replaced with a valine amino acid. This causes the resulting hemoglobin protein to form incorrectly, resulting in a sickle-shaped red blood cells that cannot function as intended

The overall goal of gene expression is to make

A structural protein that can be used by the cell

What is the name of the enzyme that fits new complementary DNA nucleotides to synthesize the new daughter strand?

DNA polymerase

Linear DNA in the human genome is packaged at several levels. Which of the following represents the levels from least packaged to most packaged?

DNA strand, nucleosomes, chromosomes

Which of the following is the main difference between in vivo and ex vivo gene therapy?

Ex vivo gene therapy occurs outside the body and In vivo gene therapy occurs inside the body

Which of the following traits are considered to be inheritable?

Eye color

To transcribe something is to make an identical copy, i.e. if the original is DNA, the transcribed copy is also DNA TRUE/FALSE

FALSE

_____ are the basic unit of inheritance that can be passed on from one generation to the next.

Genes

Which of the following best describes the definition of a gene?

Genetic information that produces a product, either proteins or RNA

Sickle-cell disease is a disorder that results in malformed hemoglobin molecules. What is the result of this in terms of hemoglobin function?

Hemoglobin has a reduced ability to bind to and transport oxygen in red blood cells

Which of the following statements best describes the structure of a hemoglobin molecule?

Hemoglobin is composed of four globin molecules, each with their own heme group that binds to and carries oxygen

_____ contain similar genes but often different alleles. After DNA replication, _____ contain identical alleles combinations

Homologous chromosomes; sister chromatids

Which of the following statements best describes how a mutation changes the shape of a protein?

If a mutation occurs during DNA replication, the affected gene may produce a protein that is misfolded

There are two main forms of non-mendelian inheritance. In ____, as observed in familial hypercholesterolemia, the dominant allele does not completely mask the recessive allele. In ______, as observed in AB blood type, two dominant alleles are expressed for the same phenotype

Incomplete dominance; codominance

Which of the following best describes the characteristics of a genetic disorder?

It is a change in the genetic information that may be passed on from one generation to the next

What is the role of the enzyme ligase in DNA replication?

It links the gaps between Okasaki fragments in the lagging strand

Mendel's experiment led him to the conclusion that individuals have two factors for each trait, which that separate during gamete formation, resulting in gametes with one factor for each trait. In addition, fertilization results in a new individual with two factors for each trait again. He referred to this as the _____

Law of segregation

The F1 generation results from the fertilization of _____

P gametes

Which of the following best describes how the environment may play a role in the expression of our genes?

Some phenotypes, including skin color, can be influenced by the environment. The genotype still determines some aspect of skin color, but the interaction with the environment, in the form of sun exposure, can cause variations in the resulting phenotype

You are given an assignment to identify a pair of human sex chromosomes from a karyotype. How would you differentiate the sex chromosomes from the autosomal chromosomes?

The sex chromosomes will be labeled XX or XY

Which of the following best explains the role of transcription in a cell?

To produce a mRNA molecule to deliver the genetic instructions outside the nucleus

Which of the following plays the role of interpreting the genetic information, from the mRNA, into a structural protein that is used by the cell?

Translation

Two parents with type A and type B blood have a child with type AB blood. How is this possible?

Type A is codominant with type B blood, so both alleles are expressed equally

For traits to be transmitted and expressed in the next generation

Will depend on the characteristic of the inherited alleles being dominant or recessive

Red blood cells are responsible for ____

gas exchange throughout the body

Crossing-over produces genetic variation during prophase I of meiosis I. This occurs when _____

homologous chromosomes come close together and a rearrangement of alleles occurs

In the human life cycle, gametes are formed through the process of ____, and all other cells are formed through the process of _____

meiosis; mitosis

Describe the movement of oxygen and carbon dioxide during gas exchange

oxygen diffuses out of the lungs into red blood cells and carbon dioxide diffuses out of red blood cells and into the lungs

Transcription starts with RNA polymerase binding to the start of the gene call a/an ____

promoter

The hemoglobin molecule is a _______

protein

DNA replication is considered to be _____ because the end product consists of one old strand and one newly synthesized strand

semiconservative

In humans, male gametes are called _____, while female gametes are called ______

sperm; eggs

During translation, a polypeptide chain is created using an RNA template. Which of the following components is responsible for bringing amino acids to the growing polypeptide chain?

tRNA

During DNA replication, the _____ strand is the one being used by the DNA polymerase to provide the new _____ strand of DNA

template; daughter

DNA strands are complementary of each other. This means if one strand has an adenine the other has a ______, and if one strand has a guanine the other has a/an ___-

thymine; cytosine

Which of the following is the overall goal of PCR?

to create several copies of a segment of DNA in a tube

Sickle-cell disease is a recessive genetic disease. This means

two copies of the recessive allele must be present in order for the disease to be expressed

Put the following steps of DNA replication in order

1) DNA helices binds to the origin of replication 2) Single-stranded binding proteins keep the double helix separated 3) Primase lays down a segment of nucleotides 4) DNA polymerase synthesizes a complementary strand

Complete the following sentence: Hemoglobin functions in ___ cells and carries _____to all cells of the body

red blood; oxygen

CRISPR may work to treat sickle-cell by targeting?

Faulty proteins of the hemoglobin gene within the genome of cells and removing and replacing those portions with normal sequences of nucleotides

Erwin Chargaff's research determined the percentage of the nitrogen bases within a strand of DNA. His work determined that

The percent of adenine is equal to the percent of thymine and the percentage of cytosine is equal to the percent of guanine

Which of the following statements best describes the orientation of the two strands of DNA?

the two strands of DNA are anti-parallel. One strand is oriented 3' to 5' and the other is oriented 5' to 3'

Which is/are the main goal(s) for obtaining and testing DNA?

-To study the number of alleles that are present in an unborn child -To determine if the exact alleles for a disease are present in an individual -To test for the presence of alleles associated with genetic disease before birth

The information contained in genes is expressed

-by folding the polypeptide into a structural protein -by translating the mRNA into a polypeptide -through transcribing the DNA segment into mRNA ALL ARE REQUIRED FOR GENE EXPRESSION

Sickle-cell disease has a physiological impact on the body because it

-changes the shape of red blood cells, which decreases the oxygen supply to the tissue -decreases the amount of oxygen picked up by red blood cells from the alveoli -can cause anemia to develop

DNA is packaged into chromosomes to

-fit within the nucleus of the cell -keep the DNA organized and accessible to the cell -compact the large amount of DNA into each cell

PCR is important because it allows scientists to

-mimic DNA replication to copy a specific segment of DNA to study -Identify criminals in forensic studies -track ancestry of organisms

Images of unreplicated chromosomes that allow researchers to organize and identify each chromosome, as well as missing or extra chromosomes are called _____

Karyotypes

Mendel crossed pea plants dominant for two different traits (tall and green pods) with pea plants recessive for those same two traits (Short and yellow pods). This cross resulted in pea plants that had combinations of all four traits (tall with green pods, tall with yellow pods, short with green pods, and short with yellow pods). Which law of inheritance best describes why this happens?

The law of independent assortment

In gene expression, the goal of translation is to

read codons and incorporate corresponding amino acids into a growing polypeptide chain

For the expression of a recessive trait, a person needs to inherit a

recessive allele from both of their parents