BIO 101 Exam 3

What was the most significant conclusion that Gregor Mendel drew form his experiments with pea plants

Traits are inherited in discrete units and are not the results of the "blending" of traits

Which of the following statement corectly describes a dihybrid cross

A dihybrid cross involves organisms that are heterozygous for two characters

Why did Mendel continue some of his experiments to the F2 generation

To observe whether or not a recessive trait would reappear

A sexually reproducing animal has two unlinked genes, one for head shape (h) and one for tail length (T). its genotype is HhTt. Which of the following genotypes is possible in a gamete from this organism

HT

When crossing an organism that is homozygous recessive for a single trait with one that is heterozygous for the same trait, what is the chance of producing an offspring with the homozygous recessive phenotype

50%

Black fur in mice (B) is dominant to brown fur (b). Short tails (T) are dominant to long tails (t). What fraction of the progeny of crosses BbTt X BBtt will be expected to have black fur and long tails

1/2

Which of the following describes the ability of a single gene to have multiple phenotypic effects

(d) Pleiotropy

Skin color in humans has a wide variety of phenotypes. The expression of this trait is caused by more than two genes. What type of inheritance pattern is responsible for this expression

Polygenic inheritance

Punett square question

Dd is in boxes 2 and 3

How do mutations affect genetic diversity in a population

Mutations produce different versions of genes

What parental blood type would NOT be able to produce a child with type O blood

AB

Which allels are dominant to each other in blood type inheritance

Alleles IA and IB are dominant to the allele i

A woman with type A blood and a man with type B blood have a baby with type O blood. What are the genotypes of the woman and the man

IAi and IBi

In his transformation experiments, which of the following results sis Griffith observe

Mixing a heat-killed pathogenic strain can convert some of the living cells into the pathogenic form

Which of the following statements correctly describes one of Chargaff's rules regarding DNA

The percentages of adenine and thymine are roughly equal, as are the percentages of guanine and cytosine in the DNA of a given species

Which of the following statements describes one difference between DNA replication in prokaryotes and DNA replication in eukaryotes

Prokaryotic chromosomes have a single origin or replication whereas, eukaryotic chromosomes have many

In which order do the necessary enzymes act to repair thymine dimer by nucleotide excision repair

nuclease, DNA, polymerase, DNA ligase

What is the function of topoisomerase

relieving strain in the DNA ahead of the replication fork

Which of the following sets of materials is required by both eukaryotes and prokaryotes for DNA replication

(c) Double-stranded DNA, four kinds of DNA nucleotides, primers, origins of replication

What nitrogenous bases are found in ribonucleic adic (RNA)

adenine, cytosine, guanine, and uracil

What process produces a complementary RNA sequence from a DNA sequence template

transcription

When genes are copied (in transcription), what form does the resulting copy take

strand of mRNA

Which molecule serves as the template during transcription

DNA

What is the function of tRNA molecules during translation

(d) They carry amino acids

Why might crop plants be genetically modified

To increase shelf life in the grocery store

Which of the following types of mutation, resulting in an error in the mRNA just after the 5' AUG start codon, is likely to have the most serious effect on the polypeptide product

A deletion of two nucleotides

What organisms contain a gene from a different species in their genome

(d) Transgenic organisms

What is the effect of a nucleotide-pair substation that results in a nonsense mutation in a gene

It introduces a premature stop codon into the mRNA

How to geneticists insert a foreign DNA that will be replicated by a recipient bacterial cell

(a) By using a plasmid

Why are some lice able to survive permethrin treatments whereas others cannot survive

(b) Some lice are naturally resistant due to genetic variation

What was Lamarck's idea about how organisms changed

He proposed that body parts changed as a result of extra use or disuse

How did the geologist Charles Lyell influence Darwin

(c) He suggested that slow, gradual changes shaped the features of Earth

Which scientist also proposed a mechanism for evolution similar to natural selection

(b) Alfred Russel Wallace

which taxonomic level would contain members that are the most similar

Genus

Which taxonomic groupings are in order from broadest to most narrow

Class, family, species

what characteristics would determine whether structures from two kinds organisms are homologous

The structures should have similar anatomy in the two organisms

How to fossils support the theory of common descent

They are a record of some intermediate organisms documenting evolutionary processes

Why are bat wings homologous to the front legs of cats

The common ancestor of bats and cate contains a similar bone structure

What embryonic structures are common in all chordates

Pharyngeal slits