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Question 01

RNA is thought to have been the primitive carrier of hereditary information rather than DNA, for which reason?

a) RNA is chemically simpler than DNA.

b) RNA can to some extent function as an enzyme, assisting the replication process.

c) The copying of genetic information is more reliable in RNA replication than in DNA replication.

Question 02

What is Eigen's paradox?

a) Large genomes require enzymes, but enzymes require large genomes.

b) In primitive conditions replication was not sufficiently reliable, so how could evolution get started?

c) Evolution requires a genetic code, but a genetic code itself must have evolved.

Question 03

The genetic code is (nearly) the same in all investigated organisms. Therefore, life must have had a single origin. True or false?

a) True

b) False

Question 04

Is it likely that DNA has started to replace RNA as the carrier of genetic information after mRNA had evolved?

a) No, it is the other way round: first DNA entered the scene, then it became advantageous to evolve mRNA.

b) Yes.

Question 05

Why did chromosomes evolve?

a) Mainly to increase the speed of gene duplication, which is much more efficient when genes are located on chromosomes compared to autonomous gene replication.

b) Mainly to ensure synchronous gene replication and a proper segregation at cell division.

Question 06

Eukaryotes differ from prokaryotes in at least the following key features.

a) Prokaryotes have no internal cytoskeleton and no chromosomes.

b) Prokaryotes have no internal cytoskeleton and no organelles.

Question 07

From what types of ancestors are mitochondria and chloroplasts derived?

a) Mitochondria from protobacteria related to present-day Rickettsiales, chloroplasts from a primitive green alga.

b) Mitochondria from an primitive archaea, chloroplasts from a cyanobacterium.

c) Mitochondria from protobacteria related to present-day Rickettsiales, chloroplasts from a cyanobacterium.

d) Mitochondria from an primitive archaea, chloroplasts from a primitive green alga.

Question 08

In the course of evolution almost all genes from mitochondria and chloroplasts have moved to the nucleus. What is the probable reason that still a small number of genes have been kept in the organellar genomes?

a) Transfer of those genes which are now present in the organellar genomes would be deleterious because their functioning generates highly reactive oxygen radicals which are mutagenic.

b) There is no functional reason of why some genes are still retained in the organelles. The process is just not yet completed, and in the future all genes are expected to have moved to the nucleus.

Question 09

A plausible reason for the origin of cell clusters as a first step to multicellularity is.

a) More efficient cooperation and defense against predation.

b) More efficient ultilization of resources and defense against predation.

c) More efficient cooperation and protection against environmental fluctuations.

d) More efficient ultilization of resources and protection against environmental fluctuations.

Question 10

The germline-soma distinction (early and absolute developmental separation of reproductive and non-reproductive cells) is found:

a) in animals and fungi, but not in plants.

b) in animals, but not in plants and fungi.

c) in animals and plants, but not in fungi.

Question 11

Do key evolutionary events often involve: (1) Previously independent units joining a larger whole, thereby losing their independence, or (2) Functional specialization: tasks previously carried out by a single unit become distributed over different and partly independent units?

a) Possibility (1)

b) Possibility (2)

c) Both possibilities

Question 12

What is the most likely reason why natural selection has produced reproductive systems in which offspring start developing from a single cell?

a) To minimize the inheritance of mutations.

b) To minimize potential conflicts between genetically different parts of the organism.

c) To maximize the potential number of offspring.

d) To maximize the efficacy of selective screening of offspring quality.

Question 13

Why is cooperation between relatives easier to understand than cooperation between unrelated individuals?

a) Relatives know each other better on average than unrelated individuals, therefore there is less uncertainty about each other's reliability.

b) Because of their relatedness the individuals involved tend to have a more similar tendency to cooperate.

c) If you help a relative to increases its reproductive success, you also enhance your own fitness, because some of the genes in your relative are identical to your own.

Question 14

What is epigenetic inheritance?

a) Inheritance via other means than through genes, e.g. how we 'inherit' our mother language .

b) Somatic inheritance of a differentiated state of the cell through successive cell divisions.

c) The inheritance of acquired characters, as originally proposed by Lamarck.

Question 15

The eukaryote cell has probably evolved from:

a) bacterial ancestors.

b) archaeal ancestors.

c) ancestors that were neither Bacteria nor Archaea, but contained genetic input from both Bacteria and Archaea.

Oxford University Press, Online Resource Centre, Chapter 15.

Chapter 15

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