Randazzo Biology Exam 2

A couple is planning to have a child. The female does not have hemophilia and is not a carrier (hemophilia is an X-linked trait); the male does have hemophilia. What is the chance that their son will have hemophilia? What is the chance their daughter will be a carrier?

0% chance that the son has hemophilia; 100% that the daughter is a carrier

In humans, the ability to roll the tongue is a dominant trait; the inability to roll the tongue is a recessive trait. If an individual homozygous dominant for this trait has a child with an individual who cannot roll his tongue, what is the chance that the child will have a heterozygous genotype?

100%

If you're interested in studying one gene within a human, and each gene has 2 alleles, then the Punnett square that you would use to predict the inheritance of the alleles would contain ________ box/boxes.

4

A diploid cell divides by meiosis, resulting in the formation of

4 haploid cells that are genetically different from each other and the parent cell

Humans have __________ chromosomes in each diploid cell, and ________ genes on each chromosome.

46 - hundreds or thousands of

A man has freckles (a dominant trait) and marries a woman that does not have freckles. If the man is heterozygous for the trait (Ff) what percentage of their children would likely have freckles? The gene is not sex-linked.

50%

Diabetes insipidus is a recessive X-linked disorder that causes the kidneys to not be able to save water. If a man without diabetes insipidus marries a woman who is a carrier for diabetes insipidus, what is the chance that they will have a SON with diabetes insipidus?

50%

In humans, normal skin coloring is dominant while albinism is recessive. Albinos are unable to produce skin pigment and are very fair in coloring. If a man and a woman are both heterozygotes, what is the chance that they will have a child with albinism?

75%

What is the sequence of the mRNA made from the gene TTACAGGTCC?

AAUGUCCAGG

An evolutionary change to better suit environrmental conditions

Adaption

Alternate forms of a gene are called

Alleles

Prior to genetic engineering, insulin for humans with insulin-dependent diabetes was extracted from pigs and cattle. Presently insulin is produced by transgenic

Bacteria

Why do chromosomes resemble the letter X when viewed during metaphase of mitosis?

Because there are two sister chromatids joined at a point in the middle (the centromere).

__________________ shows how relative degress of similarity between species on various continents coincide with the separation or joining of these continents in the past.

Biogeography

Which level is one lower than phylum?

Class

The concept that two or more species descended from a single species that existed in the past

Common Ancestry

Several populations of different species that interact with each other.

Community

The process that occurs during meiosis in which homologous chromosomes align and trade or swap sections of the chromosomes is

Crossing Over

The following are steps involved in producing recombinant DNA using human DNA and a plasmid. Which one of the following answers best reflects the proper order of these steps? Step 2:

Cut human DNA and plasmid with restriction enzyme.

After a strand of DNA has been cut with restriction enzymes, the pieces are attached again by the action of

DNA ligases

When, during the cell cycle, does the process of DNA replication take place? Describe how this process occurs.

DNA replication takes place during the S phase of the interphase portion of the cell cycle. First, DNA unwinds. Then, the two strands unzip. Free-floating nucleotides come in and attach to complementary nucleotides on the two strands using the base-pairing rule. DNA polymerase is the enzyme that binds the new nucleotides together to form new complementary strands. The result is two identical double-stranded DNA molecules.

An area with several interacting species and the physical in which they live.

Ecosystem

Which one of the following is TRUE regarding the flow of energy through an ecosystem?

Energy flows from the sun to producers and then to consumers

A representation of the evolutionary relationships between species

Evolutionary tree

If a person has different alleles for the same gene, that individual is homozygous for the trait.

False

Which of the following plants is the most fit?

Fitness can't be determined without reference to the environment

The major concerns regarding the effects of air pollution fall into the areas of smog, acid rain, destruction of the ozone layer, and

Global Warming

The physical space occupied by a population

Habitat

Describe how the process of natural selection resulted in the presence of sickle-cell anemia in some human populations.

Human populations that live in an environment where mosquitos carry malaria are most likely to have individuals with sickle-cell anemia. Individuals who are heterozygous - that is, their genotype contains one allele for normal hemoglobin and one allele for sickle-cell - are most likely to survive in a malarial environment because they have some resistance to malaria but not all of their blood cells sickle. Individuals who are homozygous for normal hemoglobin are more likely to become infected with malaria. Individuals who are homozygous for the sickle-cell allele will likely die of anemia. So, there is selection for sickle-cell but only in the heterozygous condition.

The following are steps involved in producing recombinant DNA using human DNA and a plasmid. Which one of the following answers best reflects the proper order of these steps? Step 4:

Introduce new plasmid to bacteria.

The following are steps involved in producing recombinant DNA using human DNA and a plasmid. Which one of the following answers best reflects the proper order of these steps? Step 1:

Isolate the DNA that will be recombined from both human and bacteria.

Humans belong to what Class?

Mammalia

The following are steps involved in producing recombinant DNA using human DNA and a plasmid. Which one of the following answers best reflects the proper order of these steps? Step 3:

Mix human DNA and plasmids, and add DNA ligase to join DNA fragments.

The source of new variation that can be selected is

Mutation

The theory that individuals with certain traits are more fit for their local environment and therefore are more likely to survive and reproduce is known as

Natural Selection

Bacterial ________ DNA can be easily removed from the bacterium, modified by adding a gene of interest, and then reinserted into the bacterium to be replicated.

Plasmid

Group of individuals of the same species occupy the same geographic area.

Population

Which of the following substances can be produced in mass quantities by genetic engineering?

Protein

DNA has been cut, spliced, and bound back together in a laboratory

Recombinant

Enzyme breaks the bonds between specific base pairs of DNA

Restriction

During which part of the cell cycle is DNA polymerase, the enzyme that replicates DNA, most active?

S phase of Interphase

The following are steps involved in producing recombinant DNA using human DNA and a plasmid. Which one of the following answers best reflects the proper order of these steps? Step 5:

Select bacteria that contain human DNA.

Which of the following is NOT associated with meiosis?

Somatic Cells (body cells)

Which one of the following taxonomic categories is defined as a group of organisms that are capable of interbreeding and producing fertile offspring?

Species

A father is phenotype is blood type B and a mother is blood type A. They have a child with blood type O. What are the genotypes of the father and mother?

The father must be BO and the mother must be AO.

Describe a potential benefit of a transgenic or genetically modified animal, and provide an example.

There are a few possible answers. Benefits include: higher production of animal products such as meat at a lower cost; production of useful proteins for medical uses, also called gene-pharming. Two possible examples from the videos and the book: an alteration of the salmon genome that causes it to grow to adult size much more quickly; insertion of a human gene for a valuable protein (such as a blood-clotting factor) into a goat such that they synthesize the protein in their milk.

The process of copying a sequence of DNA nucleotides into a complementary sequence of RNA nucleotides is called

Transcription

has had its genome altered by inserting a foreign gene(s)

Transgenic organism.

Compare and contrast the terms tumor, benign, malignant, and metastatic.

Tumor is a mass of rapidly dividing cells. Benign tumors have cells that are similar to the cells from which they originated and are typically not threatening. Malignant tumors invade the surrounding tissues and impair regular organ function. Metastatic tumors (or metasis) have broken away from the original tumor and spread to other organs and regions of the body.

All the following are part of a DNA molecule except

Uracil

A _____ structure had a function in an ancestor but does not currently have a function.

Vestigial

In land mammals, the pelvic girdle is the point where the leg bones attach to the rest of the skeleton. Whales also have a small pelvic girdle. This would be an example of what type of evidence for common descent?

Vestigial Structure.

Which of the following is an example of a transgenic plant?

a banana tree that has a gene with anti-fungal properties inserted into its genome

Which of the following traits could be subject to natural selection?

a plant inherits an allele that provides resistance to a herbicide

Which of the following is what scientists mean when they use the term theory?

a set of findings that are supported by repeated testing

Cattle can produce more milk by injecting them with recombinant bovine growth hormone (rBGH). Which of the following is true about the process of genetically engineering rBGH?

bacteria with the recombinant plasmid synthesize the hormone

The population size of a particular species that an ecosystem can sustain indefinitely (assuming a stable environment) is called its

carrying capacity.

The process of ________ has had a major impact on species distributions worldwide.

continental drift

Polymerase chain reaction (PCR) is useful for amplifying a small piece of DNA but is not a good technique for cloning genes because

copies of DNA produced by PCRs lack the regulatory genes and proteins required to activate genes.

A mutation is most precisely defined as

damage to a DNA molecule that alters its sequence

Primary consumers obtain nitrogen and carbon

from producers

Natural selection requires _______________ and__________________.

genetic variation within a population; selective pressure

Rising atmospheric concentrations of greenhouse gasses are causing which of the following two phenomena to occur?

global warming and global climate change

An example of a genotype is

homozygous dominant

Sister chromatids are best defined as

identical portions of a chromosome that are made when DNA replicates

One technique used to yield a transgenic animal is to

microinject the DNA of interest into an animal's egg.

Most human cells are generated by the process of _________.

mitosis

Place the following in order from smallest, simplest, least complex, to largest and most inclusive.

nucleotide, gene, chromosome, genome

DNA replication is semiconservative. This means that each of the two double stranded DNA molecules that are formed from the original double stranded DNA molecule consist of

one original DNA strand and one new DNA strand.

Omnivores differ from carnivores in that omnivores derive their energy from

plants and animals.

Many genes can contribute to a phenotypic trait, and this effect is referred to as

polygenic

Each parent contributes only one of his/her alleles for each gene to a given offspring

segregation

A restriction enzyme will

snip DNA molecules

An example of a DNA homology that provides evidence for the theory of evolution is

the DNA sequence at a particular chromosomal location is similar is all mammals, less similar between birds and mammals, and the least similar between vertebrates and starfish

Which one of the following is an example of "gene pharming"?

the production of goat milk that contains human antithrombin III protein

When two species contain identical or nearly identical proteins, and hence nearly identical DNA, this suggests

the two species share a common ancestry.