Bio Exam 3

One of the most difficult ethical issues related to DNA technology is the question, __________.

"How do we prevent genetic information from being used in a discriminatory manner?"

Flower color in snapdragons is an example of incomplete dominance. If a red-flowered plant is crossed with a white-flowered plant, the F1 generation has pink flowers. If a pink-flowered plant is crossed with a pink-flowered plant, the progeny plants will be __________.

25% red, 50% pink, and 25% white

A couple has two female children. What is the probability that their next child will be male?

50%

A man who has type B blood and a woman who has type A blood could have children of which of the following phenotypes?

A, B, AB, or O

Which of these crosses will only produce heterozygous offspring? Aa × Aa AA × Aa aa × aa AA × aa Aa × aa

AA* aa

In humans, the presence or absence of dimples is a trait controlled by a single gene. What is the genotype of an individual who is heterozygous for dimples?

Dd

What is the difference between embryonic and adult stem cells?

Embryonic stem cells are undifferentiated; adult stem cells are partially differentiated

Recombinant DNA technology has provided a mechanism for nonhuman cells to produce _____.

human proteins

Translation converts the information stored in ______ to ______.

RNA.. a polypeptide

One strand of a DNA molecule has the base sequence ATAGGT. The complementary base sequence on the other strand of DNA will be _____.

TATCCA

What is the key to the recognition of incomplete dominance?

The phenotype of the heterozygote falls between the phenotypes of the homozygotes

The process of accurately amplifying a sample of DNA is called_____.

The polymerase chain reaction

A true-breeding plant that produces yellow seeds is crossed with a true-breeding plant that produces green seeds. The seeds of all of the offspring are yellow. Why?

The yellow allele is dominant to the green allele

The world's first genetically engineered pharmaceutical product was ______.

humulin

Why, of all cell types, do embryonic stem cells (ES cells) have the greatest potential for use in the treatment of disease?

They are undifferentiated cells that have the potential to differentiate into all of the different specialized cells of the body.

In a DNA double helix an adenine of one strand always pairs with a(n) _____ of the complementary strand, and a guanine of one strand always pairs with a(n) _____ of the complementary strand.

Thymine..cytosine

Why is it that men are responsible for the gender of their children?

Unlike women, who only contribute an X chromosome, men contribute either an X or a Y chromosome. -This means that half of a man's offspring will get the X chromosome (female) and the other half will get the Y chromosome (male).

Who discovered the structure of DNA?

Watson and Crick

The sex chromosomes in humans that make an individual a male are___.

X and Y

Which of the following is an example of a transgenic organism? Which of the following is an example of a transgenic organism? a bacterium found with a plasmid that provides protection against an antibiotic a "test-tube" baby produced via in vitro fertilization Dolly, the cloned sheep a bacterium with human gene for producing insulin

a bacterium with human gene for producing insulin

A mutagen causes_____.

a change of the ribosome-binding sites

Tay Sachs disease runs in Rebecca's family. When she looked at her family pedigree, she saw a shaded circle. This represented __________.

a female with Tay Saches -the circle indicates a female, and the shading indicates the disease

RNA contains the nitrogenous base ______ instead of ______, which is only found in DNA.

uracil..thymine

Gene therapy involves____.

adding a functioning version of the defective gene to the cells of an individual

Which one of the following is a list of the four bases contained in DNA?

adenine, guanine, cytosine, thymine

Ethical dilemmas raised by DNA technology and knowledge of the human genome include ______. the potential for interfering in evolution the safety of GM foods the appropriateness of creating new plants, animals, and microorganisms the potential discrimination against people predisposed to certain diseases all of the above

all of the above

If a homozygous dominant is crossed with a homozygous recessive for a given trait, the offspring will be __________.

all of the dominant phenotype

Fetal cells may be removed along with fluid from the womb for genetic testing by a process known as __________.

amniocentesis -In amniocentesis, a small amount of the amniotic fluid containing cells is extracted for testing.

An allele is_____.

an alternative version of a gene

Which of the following best defines the term transgenic animal?

an animal containing a gene from another species

Linked genes are genes that______.

are on the same chromosome.

Chromosomes that are not sex chromosomes are called____.

autosomes

Viruses that infect bacteria are____.

bacteriophages

What do DNA and RNA have in common?

both are composed of the same nucleotides

At one point, you were just an undifferentiated, single cell. You are now made of many cells; some of these cells function as liver cells, some as muscle cells, some as red blood cells, while others play different roles. What name is given to the process that is responsible for this?

cellular differentiation

Using a cell taken from a multicellular organism to grow a genetically identical new organism is called _____.

cloning

Which of the following choices best defines "recombinant DNA technology"?

combining genes from different species

restriction enzymes_______.

cut DNA at specific nucleotide sequences

Although all of the cells in your body contain a complete set of DNA, different types of cells arise because__________.

different genes are switched on and off in each type of cell

DNA testing (profiling) can be used to determine guilt or innocence of a person suspected of a crime because __________.

every person has a unique DNA sequence

The flow of information in a cell proceeds____.

from DNA to RNA to protein

Genetically modifying human ______ cells may directly affect future generations.

gametic

A plant with the genotype AABbcc is __________.

homozygous for two different genes

In a testcross, the unknown individual (with an unknown genotype) is always crossed with a(n) __________.

homozygous recessive individual

What is the source of a viral envelope?

host cell membrane

A red bull is crossed with a white cow and all of the offspring are roan, a shade between red and white. This is an example of genes that are _____.

incompletely dominant -in incomplete dominance, the offspring have phenotypes somewhere between the phenotypes of the two parental varieties

Many human traits, such as our performance on intelligence tests or our susceptibility to heart disease, are ______.

influenced by both genes and the environment

Insurance companies having access to genetic information is potentially problematic because __________.

it may encourage discrimination against people with certain genes

John and Jane are planning a family, but each has a brother who has sickle-cell disease, so they are concerned that their children may develop sickle-cell disease. Neither John, Jane, nor their respective parents have the disease. They consult a genetic counselor, who tells them that __________.

it's possible that none of their children will have the disease, but tests on both of them will be required to make sure

In humans, the __________ determines the sex of the offspring because __________.

male... the male can contribute either an X or Y chromosome -in humans, the male parent determines the sex of the offspring because he produces both X- and Y-bearing sperm. Eggs can contribute only X chromosomes.

Transcription is the_____.

manufacture of a strand of RNA complementary to a strand of DNA

The ABO blood group in humans is an example of __________ producing four phenotypes.

multiple alleles

What is the ultimate source of all diversity?

mutation

The physical traits of an organism are called____.

phenotype

A supplemental appendix is to a book as a _______ is to a bacterial chromosome.

plasmid

Because there are potential risks associated with the use of biotechnology in agriculture, __________.

potential risks associated with biotechnology should be evaluated by a variety of U.S. regulatory agencies

In humans, the male parent determines the sex of the offspring because he produces both X- and Y-bearing sperm. Eggs can contribute only X chromosomes.

pp

In Mendel's monohybrid cross of purple-flowered and white-flowered peas, all members of the F1 generation were of the _____ phenotype because their genotype was _____ for the flower-color gene.

purple-flowered...heterozygous

What enzyme is responsible for the process seen here?

reverse transcriptase

where is translation accomplished?

ribosomes

Electrophoresis is used to __________.

separate fragments of DNA

The genetic material of HIV consists of _____.

single-stranded RNA

Gel electrophoresis separates pieces of DNA based on ______.

size

What is the function of reverse transcriptase?

t catalyzes the formation of DNA from an RNA template.

In frogs, when the nucleus of an intestinal cell of a tadpole is transferred to an egg whose nucleus has been removed (nuclear transplantation), some of the eggs will develop into normal tadpoles. This demonstrates __________.

that differentiated cells have retained all of their genetic potential

DNA profiles are used to determine whether Sam could be the father of Becky's baby. Sam is not the father if _____ genetic profile shows some bands not present in _____ genetic profile.

the baby's.. sam's or becky's

Archaeologists unearthed a human skull with a small dried fragment of the scalp still attached. They extracted a tiny amount of DNA from the scalp tissue. How could they obtain sufficient DNA for an analysis of the ancient human's genes?

use the polymerase chain reaction

Opponents of genetically modified foods are concerned about a variety of issues, including __________.

the possibility that transgenic plants may cross-pollinate with wild strains, introducing foreign genes

Sequencing the DNA of organisms such as fruit flies and yeast is useful because __________.

they have many genes that are similar to those of humans

Viral DNA makes mRNA by the process of _____.

transcription

Which of the following processes occurs in the cytoplasm of a eukaryotic cell? DNA replication transcription translation and transcription translation DNA replication and translation

translation (takes place at the ribosomes, which are found in the cytoplasm)