Tag: diversity and classification in animals

Questions Related to diversity and classification in animals

Which of the following factors affect a cell's surface area to volume ratio?
(I) Cell size
(II) Presence of selectively permeable membrane
(III) Presence of a convoluted membrane
(IV) Presence of many membrane transport protein

botany cell theory, cell specialization, and cell replacement number and shape of cells unicellular and multicellular organisms diversity and classification in animals

  1. (I) only

  2. (I), (II), (III) only

  3. (I) and (III) only

  4. (III) and (IV) only

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Correct Option: A

Refer to the following table for your possible answer.

Cell types analysed Average mass of DNA/cell (x $10^{-11}$g)
X $0.00$
Y $3.35$
Kidney $6.70$
Lung $6.70$

What is the correct identify of cell type X and Y?

botany cell theory, cell specialization, and cell replacement number and shape of cells unicellular and multicellular organisms diversity and classification in animals

  1. X-sperm cell, Y-liver cell

  2. X-liver cell, Y-smooth muscle cell

  3. X-smooth muscle cell, Y-mature red blood cell

  4. X-mature red blood cell, Y-sperm cell

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Correct Option: A

The maximum work that a standard Daniell cell can do before it stops working is
$[1 \,F = 96487\, C\, mol^{-1}\, and\, E^o = 1.1 V]$

botany cell theory, cell specialization, and cell replacement number and shape of cells unicellular and multicellular organisms diversity and classification in animals

  1. $212.271\, kJ \,mol^{-1}$

  2. $21.227\, kJ \,mol^{-1}$

  3. $721.221 \,kJ \,mol^{-1}$

  4. $71.222 \,kJ \,mol^{-1}$

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Correct Option: A

The surface area to volume ratio increase as the cell size 

botany cell theory, cell specialization, and cell replacement number and shape of cells unicellular and multicellular organisms diversity and classification in animals

  1. Unaltered

  2. Slightly increase

  3. Decrease

  4. Increase in many layers

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Correct Option: C
Explanation:

The total area on the surface of an object is called as 'Surface area' and here the object is 'cell'. While the volume is the amount of the space present inside the cell.

The volume is expressed in cubic units while surface area is expressed in square units
The surface area and volume gets affected, when size of the cell is altered i.e., either increased or decreased.
Let's see how the surface area and volume ratio gets affected...

  • When the cell size increases, the volume increases more than surface area because the volume increases in cubes while surface area increases in squares. Hence, both volume and surface area increases at different rates. And here the surface area to volume ratio decreases as the volume is more than surface area.
  • When the cell size decreases, the volume decreases at unequal rates with respect to surface area. This leads to an increase of the surface area to volume ratio.
Therefore, the surface area to volume ratio increases with the decrease in cell size.

Smaller cells have

botany cell theory, cell specialization, and cell replacement number and shape of cells unicellular and multicellular organisms diversity and classification in animals

  1. Small surface area per volume ratio.

  2. Large surface area per volume ratio.

  3. Slow exchange rate of nutrients.

  4. None of the above.

Show answer
Correct Option: B
Explanation:

Surface area to the volume ratio gets smaller as the cell gets larger. Thus, if the cell grows beyond a certain limit, not enough material will be able to cross the membrane fast enough to accommodate the increased cellular volume. Small cells, therefore, have a large surface area to volume ratio. The large surface area to volume ratio of small cells makes the transport of substances into and out of cells extremely efficient.

Large cells have a

botany cell theory, cell specialization, and cell replacement number and shape of cells unicellular and multicellular organisms diversity and classification in animals

  1. High metabolic rate.

  2. High respiration rate.

  3. Low surface: volume ratio.

  4. High surface: volume ratio.

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Correct Option: C

When a cell of $2\mu$$m$ diameter grows to double its diameter, its surface area: volume relationship will _____________.

botany cell theory, cell specialization, and cell replacement number and shape of cells unicellular and multicellular organisms diversity and classification in animals

  1. Remain the same.

  2. Become double.

  3. Reduce to half.

  4. Become undetermined.

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Correct Option: C

Metabolically active cells have

botany cell theory, cell specialization, and cell replacement number and shape of cells unicellular and multicellular organisms diversity and classification in animals

  1. Lower nucleocytoplasmic ratio.

  2. Higher nucleocytoplasmic ratio.

  3. Higher surface: volume ratio.

  4. Both B and C.

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Correct Option: D

Volumes of prokaryotic and eukaryotic cells are ........... respectively.

botany cell theory, cell specialization, and cell replacement number and shape of cells unicellular and multicellular organisms diversity and classification in animals

  1. $0.2-10\mu {m}^{3}$ and $1000-10000\mu {m}^{3}$

  2. $0.1-10\mu {m}^{3}$ and $100-1000\mu {m}^{3}$

  3. $0.1-5.0\mu {m}^{3}$ and $3-30\mu {m}^{3}$

  4. $0.1-1.0\mu {m}^{3}$ and $10-100\mu {m}^{3}$

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Correct Option: A

A bacterium divides every 35 minutes . If a culture containing $ 10^5$ cell per ml is grown for 175 minutes. What will be the cell concentration per ml after 175 mts _______________.

botany cell theory, cell specialization, and cell replacement number and shape of cells unicellular and multicellular organisms diversity and classification in animals

  1. $32 \times 10^5$ cells

  2. $5 \times 10^5$ cells

  3. $35 \times 10^5$ cells

  4. $175 \times 10^5$ cells

Show answer
Correct Option: A
Explanation:
It is given that a bacterium divides every 35 minutes,
At 0 minutes, the culture contains $ 10^5 $ cells/ml.
After 35 minutes, the culture will contain $ 2^1 \times 10^5 $ cells / ml
similarly, after 175 minutes, that is after 5 generations, the no. of cells
$ = 2^{5} \times 10^{5}$ cells/ml.
This is equal to $ 32 \times 10^{5} $ cell/ml
So, (A) is the correct answer.