Question

12. It is a model organism used to study various cell processes such as regulation of the eukaryotic cell cycle. Mutants are available for every gene in its exceptionally small genome. It can live indefinitely in either a haploid or a diploid state. Which of the following describes this organism?

a. It can reproduce only asexually.

B. It is a fungus.

C. It lacks a cell wall.

D. Its cell cycle is typically much slower than that of human cells.

E. All of the above

13. Indicate if each of the following descriptions matches lithotrophic (L), organotrophic (O), or phototrophic (P) organisms. Your answer would be a four-letter string composed of letters L, O, and P only, e.g. LLPP.

a. ( ) They feed on other living organisms or their organic products.

b. ( ) They are responsible for the current oxygen-rich atmosphere of the Earth.

c. ( ) They are all known to be prokaryotic.

d. ( ) They are the primary energy converters in hydrothermal vents in the ocean floor.

14. Which of the following groups of living organisms has the highest variation in haploid genome size?

a. Mammals

b. Fish

c. Fungi

d. Protozoa

e. Prokaryotes

15. Which of the following is NOT true regarding the tree of life?

a. Most bacteria and archaea have 1000 to 6000 genes in their genomes.

b. Eukaryotes are more similar to archaea than to bacteria with respect to the proteins that act on their DNA.

c. Most bacteria and archaea have genome sizes between one and ten million nucleotide pairs, whereas eukaryotic genomes can be millions of times larger.

d. Archaeal species were thought to belong to the eukaryotic world before sequence analysis placed them in a separate domain of life.

e. Photosynthetic bacteria are thought to be the ancestors of the eukaryotic chloroplasts.

16.Which of the following structures is exclusively found in eukaryotic cells?

a. Plasma membrane

b. Cell wall

c. Chromosome

d. Ribosome

e. Lysosome

17. Which of the following processes that happens inside a cell DOES NOT normally require consumption of free energy by the cell?

a. Replication of the genetic material

b. Import of nutrients from the environment

c. Diffusion of small molecules within the cell

d. Regulation of gene expression

e. Synthesis of enzymes that catalyze cellular reactions

18. Which of the following would you NOT expect to find in a bacterial cell?

a) Swimming using flagella

b) Having a cell wall around the plasma membrane

c) ATP production in mitochondria

d) Protein production on the ribosome

e) Sexual exchange of DNA with other bacteria

19. Judged by the average number of nucleotide-pair differences per 1000 nucleotide pairs, which of the following pairs show the highest difference?

A. The genomes of S. cerevisiae and M. musculus

B. The genomes of two different E. coli strains

C. The ribosomal RNA genes from human and E. coli

D. The transfer RNA genes in a human and M. musculus

E. The genomes of two humans

20.

Scientists discover more than ten thousand new species of living organisms every year. What is shared between all of these organisms?

A. They are made of cells, whose nuclei enclose their DNA.

B. They obtain their energy from sunlight.

C. They produce and use adenosine triphosphate (ATP).

D. Their genome contains at least 1000 genes.

E. All of the above.

Answer 1

Hi
12. Ans: B. It is a fungus.
Fungus is an eukaryote, yet single celled in nature. It divide by binary fission, can exist either as haploid or diploid. Fungus has a cell wall.

13. OPLL

14. D protozoa, they have huge variations in genome size, C-value.

15. d.
THe archaer were infact thoght to be close to bacteria, but sequence information and molecules details have put them close to eukarotes and now in a separate kingdom.

16. Lysosome
Lysosome is an organelle, only found in eukaryotic cell. A prokaryotic cell lacks organelles such as mitochondria, golgi bodies etc.

17. c.Diffusion
Diffusion is a passive process which does not need active ATP or energy utilization.

18. c. ATP production in mitochondria, as it lacks organelles.

19. a.
these two being two different family, show highest difference. The ribosome and tRNA are conserved in nature so much variation we can expect.

20. C. As all organisms on this earth utilize energy in the form of ATP, that must be the common thing shared by all species.