BIOL 2040 Final: BIOL 2040 Notes

Ploidy refers to the number of complete sets of chromosomes (genes) present in a cell. The number of chromosomes in a complete set is a fixed characteristic of a species. Humans are diploid with two sets of 23 chromosomes. Fruit flies are diploid with two sets of 4 chromosomes. Sexually reproducing organisms are diploid, each somatic cell of an organism has two complete sets ("di" is a prefix indicating 2.). To complete a life cycle and reproduce new members of a species, mating is required. Mating brings a donation from a male and a donation from a female together. However, if the male and female cells remain diploid, the fertilization will result in a tetraploid zygote. In general, these are not viable. A mechanism is needed to form special haploid cells, gametes. The diploid set is split precisely into two complete haploid sets. That mechanism is meiosis.

The complete set of chromosomes of a species is also the complete set of genes of a species, the genome. (Yes, there is a minor contribution from mitochondria and chloroplasts. Inheritance of this information is "cytoplasmic".)

Please answer the following questions:

1. How many chromosomes in a brain cell of a fruit fly? How many chromosomes are in a liver cell of a human? Explain both answers.

2. How many chromosomes are in a fruit fly unfertilized egg? How many chromosomes are in a human egg? Explain both answers.

3. Why is meiosis necessary for sexually reproducing organisms? How many chromosomes are in a human zygote? Relate the two answers.

4. What is a gene allele? Suppose there is a gene called "bingo" and it is present once in a complete haploid set. How many alleles of "bingo" does a diploid individual have? How many copies or versions of the gene "bingo" are present in a diploid individual?

5. Modern DNA sequencing clearly identifies alleles by showing the different DNA sequence of each allele. These alleles may be termed structural alleles (I coined the term for this problem.). Classical genetics only dealt with phenotypes or visible traits. As a result, alleles of genes were identified by functionality, usually normal or non-functional. Using your knowledge of gene structure and gene expression, postulate a relationship between structural alleles and functional alleles. (include relative amounts; more, less, or equal).

Question 1

The process by which RNA is synthesized using DNA as a template is …

Select one:

a. replication

b. transcription

c. translation

d. inspiration

Question 2

Which of the following occurs during meiosis but not mitosis?

Select one:

a. DNA condenses into chromosomes

b. nuclear envelop disappears

c. homologous chromosomes separate

d. sister chromatids separate

Question 3

Which part of the animal life cycle is haploid?

Select one:

a. gamete

b. zygote

c. sporophyte

d. spore

Question 4

Single celled eukaryotic organisms are …

Select one:

a. viruses

b. bacterial

c. archaea

d. protists

Question 5

Which type of cellular division results in the formation of diploid cells from a diploid parent cell?

Select one:

a. mitosis

b. meiosis

c. interphase

d. A and B but not C

e. all of the above

Question 6

A sequence of DNA that codes for a single protein is a …

Select one:

a. gene

b. ribosome

c. mRNA

d. none of the above

Question 7

Which of the following is characteristic of animals?

Select one:

a. heterotrophic

b. sexual reproduction

c. embryonic development

d. all of the above

Question 8

All genes have only two possible alleles.

Select one:

True

False

Question 9

The presence of membrane-bound organelles is characteristic of …

Select one:

a. prokaryotes

b. viruses

c. bacteria

d. eukaryotes

Question 10

What are the building blocks of proteins?

Select one:

a. fatty acids

b. amino acids

c. nucleic acids

d. all of the above

Question 11

During which phase of the cell cycle does DNA replication occur?

Select one:

a. Mitosis

b. Interphase

c. Meiosis

d. Replicosis

Question 12

Which of the following characteristic is shared among fungi and animals?

Select one:

a. autotrophic

b. heterotrophic

c. cell walls

d. absorb nutrients

Question 13

A error in DNA replication that goes unrepaired is a …

Select one:

a. chromosome

b. chromatid

c. mutation

d. none of the above

Question 14

Alternate forms of a gene are called ________.

Select one:

a. chromatids

b. chromosomes

c. ribosomal subunits

d. alleles

Question 15

The physical expression of a genotype is the phenotype.

Select one:

True

False

Question 16

In complete dominance, a heterozygous genotype results in …

Select one:

a. a recessive phenotype

b. a dominant phenotype

c. a third and unique phenotype

d. none of the above

Question 17

Which theory explains the evolution of eukaryotes from prokaryotes?

Select one:

a. phagocytosis

b. endosymbiosis

c. pinocytosis

d. none of the above

Question 18

Which scientist experimented with plants to describe patterns of inheritance?

Select one:

a. Mendel

b. Chase

c. Einstein

d. Watson

Question 19

Which cellular organelle contains aerobic cellular respiration?

Select one:

a. chloroplasts

b. mitochondria

c. nucleus

d. lysosome

Question 20

Which of the following statements is false?

Select one:

a. Haploid gametes are formed by meiosis

b. Mitosis forms genetically identical daughter cells

c. Mitosis results in the formation of four daughter cells from a single parent cell

d. Mitosis forms diploid daughter cells from a diploid parent cell

Question 21

The first forms of life on Earth were ________.

Select one:

a. plants

b. microorganisms

c. birds

d. dinosaurs

Question 22

Which of the following is used to separate chromosomes during nuclear division?

Select one:

a. cytoskeleton

b. microtubules

c. actin and myosin

d. amoeboid movement

e. all of the above

Question 23

Which generation is most dominant in more primitive plants?

Select one:

a. bryophyte

b. sporophyte

c. gametophyte

d. androphyte

Question 24

Which of the following is characteristic of plants?

Select one:

a. autotrophic

b. contain chloroplasts

c. multicellular

d. all of the above

Question 25

During which phase of mitosis do chromosome line up along the middle of the cell?

Select one:

a. prophase

b. metaphase

c. anaphase

d. telophase

Question 26

During which phase of mitosis does DNA condense into distinct chromosomes?

Select one:

a. prophase

b. metaphase

c. anaphase

d. telophase

Question 27

The process by which DNA is used as a template to make new DNA is …

Select one:

a. translation

b. replication

c. transcription

d. allocation

Question 28

Which of the following is characteristic of plant but not animal cells?

Select one:

a. chloroplasts

b. water vacuole

c. cell wall

d. all of the above

Question 29

Which meiotic division is most like mitosis?

Select one:

a. Meiosis I

b. Meiosis II

c. Meiosis III

d. Meiosis IV

Question 30

Which enzyme catalyzes replication?

Select one:

a. DNA polymerase

b. RNA polymerase

c. Ribosome

d. all of the above

Messenger RNA (mRNA)...

a) Is a structural part of a ribosome

b) Brings amino acids to DNA

c) Carries genetic information from the nucleus to the cytoplasm

d) Is a structural part of a chromosome

e) Initiates and directs chemical reactions

Mr. Potato is homozygous dominant (KK), his son, Potato Jr. is heterozygous (Kk). Based on this information, what are the possible genotypes for Mrs. Potato? (Hint: use a Punnet Square).

a) Her genotype is definitely kk

b) Her genotype is either Kk or kk

c) Her genotype is either KK or Kk

d) Her genotype is either KK, or Kk, or kk

e) Mr. Potato cannot be Potato Jr’s biological father

12. Homologous chromosomes:

a) Are members of different chromosome pairs

b) Are genetically identical

c) Carry genetic information that influences the same traits (same genes but probably different alleles)

d) Are only inherited from the mother

e) Are only inherited from the father.

“Fitness” in an evolutionary sense, refers to an individual’s:

a) Strength

b) Reproductive success

c) Aggressiveness

d) Size

e) Age at death

The fact that individuals who possess favorable traits are more likely to survive and reproduce than those who possess less favorable traits is the basis for the theory of...

a) uniformitarianism.

b) natural selection.

c) the inheritance of acquired characteristics.

d) catastrophism.

e) the fixity of species.

Even with strong selection, genetic variation of a population can be maintained because:

a) Selection only affects one gene at a time.

b) The effects of many alleles are hidden from selection by the effects of other alleles

c) Mutation constantly adds new alleles at an extremely fast rate.

d) Populations always go extinct before their gene frequencies are dramatically altered.

e) Only a and c

Gene Flow is defined as the:
a) Production of new alleles
b) New musical group in which Adam Levine will be the leading vocalist
c) Exchange of genes between populations
d) differential reproductive success of individuals
e) Process by which a DNA base gets extracted out of the nucleus to initiate the process of protein synthesis.

The basic unit of DNA is a molecule called a: a) Nucleotide

b) Base
c) Thymine
d) Prokaryoticcell e) mRNA

How many bases code for one amino acid? a) one

b) two
c) it depends on what amino acid it is d) three
e) four

Hemophilia is a condition that affects: a) more females than males
b) more males than females
c) females and males equally

d) only children born prematurely
e) individuals with a missing portion of chromosome number 5

A clear example of directional selection is:
a) Darwin finches with deeper and thicker beaks associated to a severe drought b) Sickle cell anemia in regions in which Malaria is endemic
c) Achondroplasticdwarfism
d) Fly halteres becoming fully developed wings after modification of a hox gene e) all of the above

Meiosis is evolutionarily significant because:
a) New combination of alleles can arise through independent assortment and crossing over

22.

23.

24.

25.

26.

b) It is the mechanism by which body tissues are repaired
c) It creates somatic cells that are crucial for our body organs to maintain us alive d) It allows forensics to determine the cause of death of unidentified people
e) none of the above

Homologous chromosomes:

a) Are exact copies of each other and contain exactly the same genetic material
b) Are members of different chromosome pairs
c) Are only inherited from the father
d) carry genetic information that influences the same traits (the same genes), however, each of the homologous chromosomes can contain different versions of the same gene (different alleles).

e) carry genetic information that influences different traits because each of the homologous chromosomes contains completely different genes at very different loci

How many chromosome pairs occur in a normal human somatic cell?

a) 46 b) 23 c) 22 d) 24 e) 45

What is the scientific method? Use bullet points to describe the 4 major components.

How is a hypothesis different from a theory?

List the four major components (described during class) necessary for natural selection to occur [AKA Darwin’s Four Postulates] (PDF1-3).

27. Who was Thomas Malthus? In what way(s) Malthus was influential for Darwin’s Theory of Natural Selection? Hint: populations vs resources.

29. What amino acids are being coded for by the gene segment provided below? Nucleotide triplets and their corresponding amino acids are:
ACA= Cysteine; AAA=Phenylalanine; TGG=Threonine; CCT=Glycine; GAT=Leucine; ATA=Tyrosine; AGG=Serine; TCT=Arginine

a) Threonine, serine, glycine, tyrosine, leucine, phenylalanine, arginine, cysteine.

b) Tyrosine, leucine, glycine, threonine, arginine, threonine, serine, cysteine.

c) Arginine, cysteine, serine, glycine, threonine, leucine, phenylalanine, tyrosine.

d) Phenylalanine, leucine, tyrosine, glycine, serine, threonine, cysteine, arginine.

e) Phenylalanine, leucine, tyrosine, glycine, threonine, phenylalanine, arginine, serine.