Tag: organization of life

Quizzes (19) Questions (81)

Questions Related to organization of life

Multiple choice biology organization of life the cell structure cytoplasm number and shape of cells

End of prophase is marked by?

  1. Initiation of condensation of chromosomal material

  2. Complete disintegration of nuclear membrane

  3. Reappearance of ER, Golgi body, nucleolus and nuclear envelop

  4. Alignment of chromosomes at the equator
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Prophase is the first phase of mitosis, during which chromatin condenses into visible chromosomes and the mitotic spindle begins to form. The end of prophase and transition to prometaphase is classically marked by the complete breakdown and disappearance of the nuclear membrane.

Multiple choice biology organization of life the cell structure cytoplasm number and shape of cells

Cells capable of division are

  1. Stem cells.

  2. Meristematic cells.

  3. Undifferentiated cells.

  4. All of the above.
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Stem cells are totipotent cells that can able to differentiate and divide into any type of cells of the body. meristematic cells are undifferentiated cells of the plants that can able to divide and form tissues, organs of the plant. so cells capable of division are all the cells including stem cells, meristematic cells and undifferentiated cells. Hence option D is correct.

Multiple choice biology organization of life the cell structure cytoplasm number and shape of cells

A nucleated differentiated cell that has lost the power to dedifferentiate is ____________.

  1. Nerve cells.

  2. Kidney cells.

  3. Liver cells.

  4. All of the above.
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation
A nucleated differentiated cell that has lost the power to division are nerve cells. These are the cells of nervous system and carry electrical messages and signals throughout the body. They have lost their power to division because the existing ones can grow new connections by loosing the old ones and also these cells needs oxygen and nutrients and if it divides rapidly and get packed, it will become difficult to supply and hence will starve.
So, the correct answer is option A.
Multiple choice biology organization of life the cell structure cytoplasm number and shape of cells

RBCs are

  1. Differentiated cells.

  2. Undifferentiated cells.

  3. Dedifferentiated cells.

  4. Dead cells.
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Mammalian erythrocytes also called as red blood cells are formed in bone marrow from multipotential hemocytoblast and further converted to erythroblast (normoblast). The nucleus and mitochondria of erythroblast disappear and it is converted to mature erythrocyte with haemoglobin. So RBC's are differentiated cells which lack a nucleus.

Multiple choice biology organization of life the cell structure cytoplasm number and shape of cells

Formation of meristems cork cambium from fully differentiated parenchyma cells is an example of :

  1. Differentiation

  2. Redifferentiation

  3. Dedifferentiation

  4. Regenration
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation
Cambium is the layer which forms Cork and acts as a secondary meristem from a layer of collenchyma or parenchyma immediately beneath the epidermis. The cells which produce from cork cambium will differentiate and will get mature to perform a specialized function. The living cells which lost the capacity to divide can regain the capacity of the division under certain conditions is called as 'Dedifferentiation.'
So the correct option is 'Dedifferentiation.'
Multiple choice biology organization of life the cell structure cytoplasm number and shape of cells

Any specialized plant cell that is dispersed among cells of a different kind is called a

  1. Marcophyll

  2. Xenophyte

  3. Normoblast

  4. ldioblast
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation
An idioblast is an isolated plant cell that differs from neighboring tissues. They have various functions such as storage of reserves, excretory materials, pigments, and minerals. They could contain oil, latex, gum, resin, tannin or pigments etc. So, the correct answer is "Idioblast."
Multiple choice biology organization of life the cell structure cytoplasm number and shape of cells

Dedifferentiated cells are formed in the region of

  1. Injury.

  2. Regeneration.

  3. Secondary growth.

  4. All of the above.
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

An undividable differentiated cell sometimes gains the power to divide. This process is called dedifferentiation. Wound healing after injury and secondary growth in plants are some of the best examples of dedifferentiation. Dedifferentiation is one of the mechanisms of natural regeneration. So answer D is correct.

Multiple choice biology organization of life comparison of prokaryotic vs eukaryotic cells prokaryotic cell and eukaryotic cell types of cell

Which of these statements is/are true?


(i) The surface area available for cellular functions in a prokaryotic cell is less than that in a eukaryotic cell.
(ii) The total genome size of a prokaryotic cell is always less than that of a eukaryotic cell.
(iii) Unlike eukaryotes, no special respiratory organelles are found in prokaryotes. Hence they respire at a much less rate than eukaryotes.
(iv) Eukaryotic cells show various membrane-bound organelles such as chloroplasts and nucleus while ribosomes are the only membrane-bound organelles found in prokaryotes.

  1. (i) and (ii)

  2. (iv) only

  3. (iii) only

  4. (i), (ii) and (iv)
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

The cellular and genomic organisation of prokaryotes are fundamentally different from that of eukaryotes. 

  • Prokaryotic cells have a small, simple structure compared to eukaryotic cells. They have less surface area per volume. Prokaryotes have simpler and smaller genomes than eukaryotes. In the majority of prokaryotes, the genome consists of a ring of DNA with few associated proteins. 
  • The eukaryotic genome is larger, organised into chromosomes, and is complexed with histone proteins. 
  • Unlike eukaryotes, prokaryotes do not have membrane-bound organelle for respiration but many enzymes needed for cellular respiration are attached to the plasma membrane, which may fold and extend into the cell. Ribosomes are the only cytoplasmic organelles in prokaryotes and they are not membrane-bound.
So, the correct answer is '(i) and (ii)'.