Tag: basics of cell

Questions Related to basics of cell

Extra nuclear DNA is found in

component of the cell cell and cell organelles cell organelles cell: the unit of life biology cell as structural and functional unit basics of cell

  1. Lysosome and chloroplast

  2. Chloroplast and mitochondria

  3. Mitochondria and lysosome

  4. Golgi and endoplasmic reticulum

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Correct Option: B
Explanation:

Extrachromosomal DNA is found in chloroplast and mitochondria. Extrachromosomal DNA is any DNA that is found outside of the nucleus of a cell. It is also referred to as extranuclear DNA  or cytoplasmic DNA. Most DNA in an individual genome is found in chromosomes. Extrachromosomal DNA is often used in research of replication because it is easy to identify and isolate.

Which of the following is not common in chloroplasts and mitochondria?

component of the cell cell and cell organelles cell organelles cell: the unit of life biology cell as structural and functional unit basics of cell

  1. Both are present in animal cells.

  2. Both contains their own genetic material.

  3. Both are present in eukaryotic cells.

  4. Both are present in plant cells.

Show answer
Correct Option: A
Explanation:

Extrachromosomal DNA is any DNA that is found outside of the nucleus of a cell. It is also referred to as extranuclear DNA or cytoplasmic DNA. This extra chromosomal DNA is present in both mitochondria and chloroplast. Chloroplast and mitochondria are present in the plant cell but chloroplast is absent in the animal cell. They both are present in eukaryotic cells.

Select the wrong statement from the following.

component of the cell cell and cell organelles cell organelles cell: the unit of life biology cell as structural and functional unit basics of cell

  1. Both chloroplasts and mitochondria contain an inner and outer membrane.

  2. Both chloroplasts and mitochondria have an internal compartment, the thylakoid space bounded by the thylakoid membrane.

  3. Both chloroplasts and mitochondria contain DNA.

  4. The chloroplasts are generally much larger than mitochondria.

Show answer
Correct Option: B
Explanation:

Option b is incorrect because a  thylakoid is a membrane-bound compartment inside chloroplasts and cyanobacteria and not present in the mitochondrion. They are the site of the light-dependent reactions of photosynthesis. Thylakoids consist of a thylakoid membrane surrounding a thylakoid lumen. Chloroplast thylakoids frequently form stacks of disks referred to as grana. Grana are connected by intergranal or stroma thylakoids, which join granum stacks together as a single functional compartment.

Autonomic genome system is present in

component of the cell cell and cell organelles cell organelles cell: the unit of life biology cell as structural and functional unit basics of cell

  1. Ribosomes and chloroplasts

  2. Mitochondria and ribosomes

  3. Mitochondria and chloroplasts

  4. Golgi bodies and mitochondria

Show answer
Correct Option: C
Explanation:

According to the endosymbiotic theory about origin of chloroplast and mitochondria, both of these cell organelles were independent organisms that became lodged inside a eukaryotic cell during evolution. 

As both chloroplast and mitochondria were once upon a time independent organisms they have their own genetic material as well as protein synthesis machinery. 

Thus, they have their own autonomous genome system.

Given below are assertion and reason. Point out if both are true with reason being the explanation (A), both true but reason is not correct explanation (B), assertion true but reason is wrong (C), both are wrong (D)
Assertion. Mitochondria and chloroplasts have their own genome
Reason. Endoplasmic reticulum and Golgi body are the cell organelles which have their own DNA.

component of the cell cell and cell organelles cell organelles cell: the unit of life biology cell as structural and functional unit basics of cell

  1. A

  2. B

  3. C

  4. D

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Correct Option: C

Movement of ten electrons from mitochondrial NADH molecules produces water molecules

component of the cell cell and cell organelles cell organelles cell: the unit of life biology cell as structural and functional unit basics of cell

  1. 20

  2. 15

  3. 10

  4. 5

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Correct Option: D

In yeast mitochondria UGA codes for:

component of the cell cell and cell organelles cell organelles cell: the unit of life biology cell as structural and functional unit basics of cell

  1. Termination codon

  2. Initiation codon

  3. Tryptophan

  4. Tyrosine glycerate concentration

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Correct Option: A

Which of the following organelles contain circular DNA.

component of the cell cell and cell organelles cell organelles cell: the unit of life biology cell as structural and functional unit basics of cell

  1. Peroxisomes and mitochondria

  2. Mitochondria and Glgicomplex

  3. Chloroplasts and Lysosomes

  4. Mitochondria and chloroplast

Show answer
Correct Option: D
Explanation:
Mitochondria and chloroplast are the organelles that show the presence of circular DNA.
The circular DNA in chloroplast is self-replicating and is known as cpDNA. It is involved in the synthesis of some intra-organelle proteins.
The mitochondrial circular DNA is self-replicating and is called mt DNA. It is also involved in the synthesis of some intra-organelle proteins.
Thus the correct answer is option D.

How many organelles of a eukaryotic animal cell possess their own DNA?

component of the cell cell and cell organelles cell organelles cell: the unit of life biology cell as structural and functional unit basics of cell

  1. 1

  2. 2

  3. 3

  4. 4

Show answer
Correct Option: B
Explanation:

Mitochondria and chloroplasts are the only two organelles of animal and plant cells that contain their own DNA. They not only contain their own DNA, but they also have their own ribosomes. These little protein-making machines are given information from the DNA to build certain proteins.

So, the correct option is '2'.

Mitochondria and chloroplasts are believed to be bacterial endosymbionts of cells because

component of the cell cell and cell organelles cell organelles cell: the unit of life biology cell as structural and functional unit basics of cell

  1. They have their own nucleic acids.

  2. Their membranes resemble those of cyanobacteria.

  3. They do arise de novo.

  4. All of the above.

Show answer
Correct Option: A
Explanation:

Mitochondria and Chloroplasts are the only cell organelles other than nucleus coated with double membrane. They have their own DNA and protein synthesizing machinery as well. One explanation for a cell organelle to have its own DNA is that these organelles were separate organisms. The chloroplast was an autotrophic cyanobacteria and the mitochondria was a separate heterotrophic organism which later on became lodged into a eukaryotic cell as endosymbionts.