DNA, Genetics, and Evolution Flashcards

Flashcards of lecture notes on DNA, Genetics, and Evolution

DNA controls the formation of ____ that allow you to express your ___

lipids, cell membranes

What does this diagram show?

DNA contains instructions for making proteins

How does the DNA in body cells compare to each other?

The DNA in body cells is the same, but cells use different parts of DNA

Cells build specific proteins, like enzymes, based on the….

sequence of nitrogen bases in the DNA

What is the result of mitosis?

Two daughter cells with the same DNA as the parent cell.

Which of the following is true of interphase?

Interphase is longer than mitosis.

Component Y is a . . .

Phosphate

What is the complementary DNA Strand?

adenine, thymine, cytosine, guanine

transcription

A strand of mRNA is made from a DNA template.

translation

A polypeptide chain is made based on the sequence of bases in a strand of mRNA.

DNA replication

DNA is copied before cell division may start.

Which mRNA sequence complements the DNA sequence below?

Sequence B

Which statement is true about the nitrogen bases in DNA and RNA?

Uracil is found in RNA only. Thymine is found in DNA only.

Which tRNA anticodon will complement this mRNA codon?

Anticodon B

Place the four images from the cell cycle in the correct chronological order.

Image C, image D, image B, image A

If you were to examine a sample of 1000 cells, in which of the phases listed below would you expect to find most of the cells?

Interphase

What is the role of DNA?

Contains instructions for making proteins that run cellular processes.

Both DNA and RNA:

contain phosphate groups

The result of replication is two DNA molecules:

each with one original strand and one new strand

What is the function of DNA in cells?

It stores the information that directs the ribosomes in protein synthesis.

Each strand of the DNA molecule can be used to make another strand during replication. This is because the two sides are to each other.

Complementary

Griffith’s transformation experiments

caused harmless bacteria to become deadly.

Using radioactive tracers to determine the interactions of bacteriophages and their host bacteria, Hershey and Chase demonstrated without question that

DNA is the molecule that stores genetic information in cells.

Which of the following is not part of a molecule of DNA?

ribose

The entire molecule shown in the diagram above is called a(n)

nucleotide

The scientists credited with establishing the structure of DNA are

Watson and Crick.

X-ray diffraction photographs by Wilkins and Franklin suggested that

DNA molecules are arranged as a tightly coiled helix.

During DNA replication, a complementary strand of DNA is made for each original DNA strand. Thus, if a portion of the original strand is CCTAGCT, then the new strand will be

GGATCGA.

The attachment of nucleotides to form a complementary strand of DNA

is accomplished by DNA polymerase.

Which of the following is not true about DNA replication?

The process is catalyzed by enzymes called DNA mutagens.

The enzymes that unwind DNA are called

DNA helicases.

RNA differs from DNA in that RNA

All of the above

chemically similar to DNA except that its sugars have an additional oxygen atom, and the base thymine is replaced by a structurally similar base called

uracil.

Transcription proceeds when RNA polymerase

binds to a strand of DNA.

Each nucleotide triplet in mRNA that specifies a particular amino acid is called a(n)

codon.

What is the portion of the protein molecule coded for by the mRNA: CUCAAGUGCUUC ?

Leu—Lys—Cys—Phe

What is the correct sequence of anticodons for the codons in the mRNA: CUCAAGUGCUUC?

GAG—UUC—ACG—AAG.

Each of the following is a type of RNA except

carrier RNA.

Transfer RNA

carries an amino acid to its correct codon.

During translation, the amino acid detaches from the transfer RNA molecule and attaches to the end of a growing protein chain when

the transfer RNA anticodon binds to the messenger RNA codon.

Cells must control gene expression so that

their genes will be expressed only when needed.

Enzymes that cut DNA molecules at specific places

are restriction enzymes.

Watson and Crick built models that demonstrated that

DNA is made of two strands that twist into a double helix.

The enzymes responsible for adding nucleotides to the exposed DNA template bases are

DNA polymerases.

During transcription, the genetic information for making a protein is “rewritten” as a molecule of

messenger RNA.

In order for translation to occur, mRNA must migrate to the

ribosomes.

Sex cells, found in the reproductive organs of men and women, are known as

Gametes

Which of the following describes a homologous pair?

A pair of chromosomes that have the same genes, but different alleles. One is inherited from each parent.

The process that produces gametes is called ___

Meiosis

Which of the following processes help to produce genetic variation in offspring?

All answers are correct.

How many rounds of cell division does the original cell undergo during meiosis?

2

What is the man’s genotype?

Bb

What are the genotypes of the Brown-eyed children?

Bb

What is the genotype of the mother?

bb

What term best describes the genotype of the father?

Heterozygous

If Parent A (Type AB blood) is crossed with Parent B (Type O blood), which of the following is not a possible offspring for that cross?

Offspring A- Type O blood

If a somatic (body) cell in an organism has 48 chromosomes, how many chromosomes would an egg cell contain?

24

If a person has type AB blood then they have an A allele and a B allele in their genome. This means that…

Both the A and B allele are expressed

A red snapdragon and a white snapdragon are crossed. All of the resulting snapdragons are pink. This is an example of what pattern of inheritance?

Incomplete Dominance

What pattern of inheritance is demonstrated by this image?

Codominance

In cattle, roan color (mixed red and white hairs) occurs in the heterozygous offspring of red and white homozygotes. Cross 2 Roan cattle. What percentage of the off spring will have Roan coloring?

50%

Which of the following statements describes the genotype of this homologous pair?

Heterozygous for genes A, I, and T

You cross two red-eye flies. Red is dominant to white, and the gene for eye color is found on the X chromosome. The image below shows the results of the cross. What are the phenotype probabilities?

50% female red eyes, 25% male red eyes, 25% male white eyes

Color-blindness is a RECESSIVE, sex-linked disorder. Rob is colorblind, and Linda carries the gene for color-blindness. What is the probability that their children could be carriers?

50%

A woman who is heterozygous for Type A blood married a man with Type B blood, and they had a child with type O blood. Which 2 statements are true:

None of the options listed are true.

In fruit flies, eye color is located on the X chromosome. Red eye color is dominant to white eyes. Cross a Heterozygous red eye female with a red-eyed male. What is the probability that any of the offspring will have white eyes?

0%

Snapdragons are flowers. Their flower colors follow Incomplete Dominance rules for inheritance. Flowers can be white, red, or pink. What do you expect the GENOTYPE ratio to be if two pink snapdragons were to produce offspring?

4. 1 RR: 2 RW: 1 WW

The scale-color of a made-up lizard is inherited as a codominant trait. The homozygous phenotypes of the trait are yellow scales, and blue scales. What do you expect the heterozygous form of the trait to look like?

some yellow scales, and some blue scales

Different versions of genes for a trait, such as the gene for brown eyes and the gene for green eyes, are called _

Alleles

In reality, most traits in humans, and other organisms, are too complicated to predict using Punnett Squares. These traits are controlled by more than one gene, which is called a __ pattern of inheritance?

Polygenic

If a disease was sex-linked recessive, what would you expect to see, on average, in the family over generations?

More males would have the disease than females

A father can pass an x-linked recessive trait to his son

False

What is the genotype of individual number 1?

X^H X^h

What is the genotype of individual number 3?

X^hX^h

What is the genotype of individual number 4?

X^H Y

What is the probability of Individual #14 having children with hemophilia if their spouse has no family history of this disorder?

0%

What is the probability of Individual #10 being a carrier of the Hemophilia allele?

100%

How many bands would be expected in gel electrophoresis for a sample that has one mutation in the p53 gene?

two bands

Which generation shows that a son died as an infant from cancer according to the pedigree?

Generation 2

Valerie's children have decided to undergo genetic testing for the P53 gene. Below are the results from their gel electrophoresis genetic test. Which of the statements below are true?

Children 2, 3, and 5 have Li-Fraumeni Syndrome

Li-Fraumeni Syndrome is best characterized as which of the following?

An inherited mutated allele that increases the risk of a person developing cancer

Which pattern of inheritance does Li-Fraumeni Syndrome follow?

Autosomal dominant

meiosis 2.

1.Separation of homologues occurs during

2. The difference between anaphase of mitosis and anaphase I of meiosis is that

chromatids do not separate at the centromere in anaphase I.

When crossing-over takes place, chromosomes

exchange corresponding segments of DNA.

Which of the diagrams above depicts a cell at the end of meiosis I?

D

Which of the diagrams above depicts a cell at the end of meiosis 2?

A

Which of the diagrams above depicts a cell at the end of mitosis?

A

Which of the following does not provide new genetic combinations?

cytokinesis

During cytokinesis in the female, what divides unequally?

the cytoplasm

Mendel's law of segregation states that

the two alleles for a trait separate when gametes are formed.

The phenotype of an organism

is the physical appearance of a trait.

If an individual possesses two recessive alleles for the same trait, the individual is said to be

homozygous for the trait.

An individual heterozygous for a trait and an individual homozygous recessive for the trait are crossed and produce many offspring that are

of two different phenotypes.

Tallness (T) is dominant to shortness (t) in pea plants. Which of the following represents a genotype of a pea plant that is heterozygous for tallness?

Tt

Mendel's finding that the inheritance of one trait had no effect on the inheritance of another became known as the

law of independent assortment.

Refer to the illustration above. The child represented in box 1 in the Punnett square would

be heterozygous for freckles.

Refer to the illustration above. Which box in the Punnett square represents a child who does not have freckles?

box 4

The unknown genotype of an individual with a dominant phenotype can be determined using

a test cross.

If a characteristic is sex-linked, it

occurs most commonly in males.