LectureQuiz Flashcards
(30 cards)
In Griffith’s transformation experiments?
mice infected with heat-killed virulent bacteria and live nonvirulent bacteria developed pneumonia and died
Avery, MacLeod, and McCarty’s experiments revealed that the transforming principle had all of the following properties except:
its activity was destroyed by treatment with proteases
When Hershey and Chase performed their radioactive phage labeling experiment, what finding allowed them to conclude that the virus injects DNA and not protein into its host?
most of the radioactive DNA was inside the bacteria
Which statement correctly describes the composition of DNA?
a five-carbon sugar, a phosphate group, and one of four nitrogenous bases
The genome of an organism contains 24% guanine; therefore, its genome also contains ______________% thymine and ______________% cytosine.
26 thymine; 24 cytosine
If we think of the DNA double helix as a twisted ladder, what makes up the rungs or steps of the ladder?
purines and pyrimidines
Which nucleotide sequence is complementary to the DNA sequence 5’-TCATGG-3’?
3’-AGTACC-5’
You decide to repeat the Meselson-Stahl experiment, except this time you plan to grow the cells on light 14N medium for many generations and then transfer them to heavy 15N medium and allow them to grow for 2 additional generations (2 rounds of DNA replication). If the semiconservative model of DNA replication is correct, what is the expected distribution of DNA in the density gradient after two rounds of replication?
One band of intermediate density and one band of heavy density
Adding nucleotides onto a growing DNA strand during DNA replication in cells occurs in ______________.
the 5’ →3’ direction only
Which statement describes a difference between meiosis I and meiosis II?
Homologous chromosomes separate during meiosis I; sister chromatids separate during meiosis II
Homologous chromosomes undergo recombination during ______________.
prophase I
What is the difference between sister chromatids before and after anaphase II?
Before anaphase II, the sister chromatids form a single chromosome; after anaphase II, each sister chromatid is an individual chromosome
In meiosis I, _______ determines the number of chromosomes in the gametes. This is an essential process that serves to keep the same number of chromosomes in the embryo that will be formed when the gametes get together.
reductional division
How many unique daughter cells result from meiotic or mitotic cell division of a cell, which has three homologous chromosome pairs?
There will be no unique daughter cells after mitosis; there will be four different daughter cells after meiosis, and these cells will also be different from the parental cell
What biological process can separate genes that are on the same chromosome?
Crossing over
If your mother and father both have Tay Sachs disease, which is caused by a recessive allele, the odds of you having Tay Sachs disease are __________.
1
The ability of an individual heterozygous for two different genes to produce the four possible gamete types in equal numbers reflects Mendel’s Law(s) of
Segregation and Independent Assortment
A man and woman are each heterozygous for the autosomal recessive disorder sickle cell anemia. If they want to have three children, what is the probability that only one of the children will have sickle cell anemia?
9/64
A couple are both heterozygous for the dominant allele for freckles. They want to have three children. What is the probability that all three children will have freckles?
27/64
Your mother has Tay Sachs disease, which is a recessive trait. Your father has sickle cell anemia, which is also a recessive trait. You discover that your new father- in-law has Tay Sachs and sickle cell anemia. If neither you nor your spouse has either Tay Sachs or sickle cell anemia, what are the odds that your first child will have both Tay Sachs and sickle cell anemia?
1/16
In eggplant, the deep purple allele CP is incompletely dominant over the white allele CW. If you cross a violet eggplant (CPCW) with a white eggplant (CWCW), what percentage of the progeny will be white?
50%
In the case of complete dominance, if a plant has a ______________ genotype for a particular trait, its phenotype will have the ______________trait.
heterozygous; dominant
From his experiments, Mendel concluded that each individual carries two factors, or ______________, that govern the inheritance of each trait. Different versions of each factor are known as ______________.
genes; alleles
Events X and Y are independent of each other. If the probability of event X occurring is 1 in 6, and the probability of event Y occurring is 1 in 8, the probability of both events occurring is ______________.
(1/6)(1/8) = 1/48
