Question

1: Compairing the sequences of the 16S and 18S rRNAs has placed living organisms into the foloowing three Domains:

(a) Archaea, Eucarya, Fungi

(b) Eucarya, Fungi, Protista

(c) Plants, Animals, Prokaryotes

(d) Plants, Animals, Protista

(e) Eucarya, Archaea, Bacteria

2: During photosynthesis the enzymes that synthesize carbohydrates are located in the chloroplast's:

(a) Grana

(b) Stroma

(c) Thylakoids

(d) Chloroplast envelope

(e) The lumen

3: What is the amino acid R-group for cysteine?

(a) -H

(b) -OH

(c) -SH

(d) An organic acid

(e) A non polar ring

4: Enzymes are transported to the lysosome from the TGN i versiclescoated with what Protein?

(a) COPII

(b) Dynamin

(c) Lysozyme

(d) Clathrin

(e) Acid phosphatase

5: when a mitochondrial chaperone helps a mitochondrial matrix protein into the matrix by biased diffusion, the chaperone is said to be acting as a(n):

(a) Unbiased diffuser

(b) Hammer

(c) Biased diffuser

(d) Screw driver

(e) Ratchet

Answer 1

1. Carl Woese and George Fox classified all the living organisms into three domains based on the nucleotide sequences of the 16S and 18S rRNAs. The three domains are bacteria, archaea, and eukarya. So, the correct option is option E, eukarya, archaea, bacteria.
2. Light reactions take place in the thylakoid membrane of chloroplasts and the energy generated during light reactions is used to fix carbon from carbon dioxide to form glucose. This reaction known as the Calvin cycle takes place in the stroma of the chloroplasts. So, the correct option is option B, Stroma.
3. Cysteine is a sulfur containing amino acid. The R-group of cysteine has a –SH group. So, the correct option is option C, -SH.
4. Enzymes that are destined for lysosomes are transported from the TGN in clathrin coated vesicles. So, the correct option is option D, Clathrin.
5. A polypeptide diffusing into the mitochondrial matrix would be repeatedly bound by the chaperones so that the polypeptide is prevented from diffusing backwards. This mechanism of chaperone action is known as biased diffusion and the chaperone is said to be acting as a “Brownian ratchet”. So, the correct option is option E, Ratchet.