BIOL 1020 Final Auburn University

Define mutation

a random change in an allele

Mutations are caused by selective pressure in the environment. True or False

False

The same mutation could be advantageous in some environments but deleterious in others. True or False

True

The appearance of dark-colored volcanic rock caused the mutation from black fur to appear in the rock pocket mouse population? True or False

False

Both DNA and RNA contain...

phosphate groups

The number of consecutive mRNA bases needed to specify an amino acid is

3

If the sequence of bases in a section of DNA is 5'—TAGGCTAA -3', what is the corresponding sequence of bases in mRNA?

3'—AUCCGAUU-5'

What is a ribozyme

An RNA with enzymatic activity

What is an anticodon?

3 consecutive nucleotides in tRNA

The process of copying genetic information from DNA to RNA is called

Transcription

A transcription start signal is called

A promoter

A type of RNA that binds to a specific amino acid during translation is

Transfer RNA

Which of the following statements describes a eukaryotic chromosome?

A single linear molecule of double-stranded DNA plus proteins

The leading and the lagging strands differ in that

The leading strand is synthesized in the same direction as the movement of the replication fork, and the lagging strand is synthesized in the opposite direction

In E.coli, there is a mutation in a gene called dnaB that alters the helicase that normally acts at the origin. Which if the following would you expect as a result of this mutation?

No replication fork will be formed

After DNA replication is completed

Each new DNA double helix consists of one old DNA strand and one new DNA strand

Which of the following represents the order of increasingly higher levels of organization of chromatin?

Nucleosome, 30 nm chromatin fiber, looped domain

If a cell were unable to produce histone proteins, which of the follow would be a likely effect?

The cell's DNA couldn't be packed into its nucleous

When chromosomes replicate...

The two DNA strands separate and each is used as a template for synthesis of a new strand

Sequence of subunits in the DNA "backbone" is

-phosphate—sugar—phosphate—sugar—phosphate—sugar--

One organism has 18% cytosine in its genome, how much adenine does it have?

32%

Two strands of duplex DNA are complementary in sequence and arranged in antiparallel fashion. What is the base sequence of the complementary strand to the following: 5'—ATGCTCGACTTACAT—3'

5'—ATGTAAGTCGAGCAT—3'

Which of the following can be found in both DNA and RNA nucleotides?

Phosphate, ribose, pyrimidine, purine, adenine, guanine, cytosine

In a DNA double helix structure, what is the function of hydrogen bonds?

Holding the complementary base pairs together

What is a telomere?

Special nucleotide sequence

What is the difference between chromatin and chromosomes?

Chromatin condenses to from chromosomes

What is DNA packaging?

Pairing DNA with other proteins and putting it together to form chromatin

When Mendel crossed yellow-seeded and green-seeded plants, al the offspring were yellow seeded. When he took these F1 yellow-seeded plants and crossed them to green-seeded plants, what genotypic ratio was expected?

1:2:1

A woman is red-green colorblind, and she mates with a man who has normal color vision. Knowing that red-green color blindness is controlled by a gene on the X chromosome, what can you predict for their children with regard to inheritance of color vision?

All of the boys and none of the girls will be color blind

A woman with normal color vision, but whose father is red-green colorblind mates with a man who is red-green colorblind. Knowing that red-green colorblindness is controlled by a gene on the X chromosome, what can you predict for their children with regard to inheritance of color vision?

Half of the boys and half of the girls will be colorblind

What is true of genetic linkage?

The closer the two genes are on a chromosome, the lower the probability that a crossover will occur between them, linked genes are found on the same chromosome, the frequency of recombination of two linked genes that are far apart from each other is greater than those closer ones, crossing over can break the linkage

What are the sources of variety in sexually reproducing species?

Crossing over, random fertilization, and independent assortment

The region of the chromosome occupied by a gene is called a

Locus

A recessive gene is one

Whose effect is masked by a dominant allele

If, in a heterozygous individual, only one allele is expressed in the phenotype, that allele is

Dominant

When the two gametes that fuse to form a zygote contain different alleles of a given gene, the offspring is

Heterozygous

What is the difference between phenotype and genotype?

Genotype is the set of alleles an organisms carries for a given trait and phenotype is the observable characteristics

What is the difference between dominant and recessive alleles?

Dominant alleles overpower recessive alleles, and recessive alleles are only expressed when two are present

Explain the law of segregation

States that allele pairs separate or segregate during gamete formation

What is genetic linkage?

Tendency of alleles that are close together on a chromosome to be inherited together during the meiosis phase of sexual reproduction

What is genetic mapping?

How to identify the locus of a gene and the distances between genes

What is a hemizygous? What is a carrier?

When only one copy of a chromosome is present; someone that carries the alleles for a gene

What is pedigree analysis?

A series of symbols used to express outcomes of children based on parents

What is non-disjunction?

When homologous chromosomes don't separate correctly in nuclear division

__________ separates homologous chromosomes in a diploid cell to produce haploid daughter cells containing one copy of each type of chromosome

meiosis

When homologous chromosomes pair up and exchange DNA

Prophase 1

When homologous chromosomes separate

Anaphase 1

When the sister chromatids of each chromosome separate

Meiosis 2

When ploidy is reduced

Meiosis 1

Typical human cells, if normal, have __ chromosomes during anaphase in mitosis.

92

How do the two memebers of a pair of homologous chromosomes typically differ from each other?

The precise sequence of the DNA within each of the chromosomes

What typically occurs during anaphase 1?

Sister chromatids travel together and homologous chromosomes segregate

Substrate-level phosphorylation occurs _____

In both glycolysis and the citric acid cycle

The primary role of oxygen in cellular respiration is to

Act as an acceptor for electrons and hydrogen, forming water

The end product of glycolysis is

Pyruvate, the starting point for the pyruvate oxidation and krebs cycle, the starting point for the fermentation pathway

Products of glycolysis include

Pyruvate, ATP, NADH

CO2 is released during which of the following stages if cellular respiration?

Oxidation of pyruvate to acetyl CoA and the citric acid cycle

The energy production per glucose molecule through the citric acid cycle is

2 ATP, 6 NADH, 2 FADH2

The chemisosmostic hypothesis is an important concept in our understanding of cellular metabolism in general because it explains

How ATP is synthesized by a proton motive force

As protons flow through the ______, energy is release and exploited to combine ADP and inorganic phosphate to from ATP.

ATP

Muscle tissue make lactic acid from pyruvate so that you can _____

Regenerate (oxidized) NAD+

Why do you breathe more heavily during exercise?

Because your cells need more O2 and are producing more CO2

What is an autotroph?

Almost all plants - self feeders, produce organic molecules from O2 and other inorganic raw materials

What is a photautotroph?

Organisms that use light as a source of energy to synthesize organic substances

Explain chloroplasts

Found anywhere a plant is green, site of photosynthesis

Explain thykaloid

3rd memebrane system made of sacs, separates stroma from thykaloid space inside of sacs

Explain stroma

dense fluid egion outside the thylakoid membranes in chloroplasts.

Explain chlorophyll

Green pigment that gives leaves their color

Explain stomata

Microscopic pores that allow CO2 to enter the leaf and O2 to leave the leaf

3 photosynthetic pigments

chlorophyll a, chlorophyll b, and carotenoids

Where does light reaction occur?

Chloroplasts

The function of both alcohol and lactic acid fermentation is to

Regenerate NAD+

How many NADHs are produced totally by breaking down one glucose molecule?

10

How many pyruvates can be produced by the breaking down of one glucose molecule?

2

How many FADH2s are produced totally by breaking down one glucose molecule?

2

How many CO2 molecules are produced totally by breaking down one glucose molecule?

6

How may CO2 molecules are produced in ETC by breaking down one glucose molecule?

0

How many ATPs are produced through substrate-level phosphorylation by breaking down one glucose molecule?

4

How many ATPs are produced through oxidative phosphorylation by breaking down one glucose molecule?

26-28

How many ATP molecules are produced totally by breakind down one glucose molecule?

30-32

In chemiosmosis, ATP is produced as hydrogen ions (protons) pass through:

ATP synthase

Describe the process of glycolysis

Represents the first stage in chemical oxidation of glucose by a cell, consumes 2 ATPs to breakdown 1 glucose, produces 2 net ATPs

Products of the Krebs Cycle

CO2, O2, FADH, ATP

During the citric acid cycle, each acetyl group produces

1 ATP, 4 NADH, and 1 FADH2

What are redox reations?

Chemical reactions where the transfer of one or more electrons occurs

4 stages of aerobic respiration

glycolysis, pyruvate oxidation, krebs cycle, oxidative phosphorylation

Reactant and products of glycolysis

Reactants: glucose, atp, NADs

Products: pyruvate, NADH, ATP, h2o, h+

Reactants and products of pyruvate oxidation

Reactants: pyruvate, NAD+, CoA

Products: acetyl CoA, NADH, H, CO2

What is chemiosmosis? What stage does it occur? What is it used for?

The movement of protons, occurs in oxidative phosphorylation, used as a driving force to produce ATP

When chemical, transport, or mechanical work is done by an organism, what happens to the heat generated?

It is lost to the environment

When ATP releases some energy, it also releases inorganic phosphate. What happens to the inorganic phosphate in the cell?

It may be used to form a phosphorylated intermediate

What binds to the active site of an enzyme?

Substrates and competitive inhibitors

Enzymes are...

Proteins

An enzyme can only bind one reactant at a time. True or false

False

An enzyme speeds up a chemical reaction in the cell, but can only be used once. True or false

False

Why do cells not use changes of temperature to modify the rates of chemical reactions?

Most proteins begin to denature as temperature increases

What is energy?

Capacity to cause change

Two types of energy

Kinetic and thermal

First law of thermodynamics

Energy cannot be created or destroyed, only change form

Second Law of thermodynamics

Energy conversion increases the entropy in the universe