Biology · Science General

Cell Biology and Structure

3,221 Questions

Cell biology focuses on the structure and function of cellular organelles. Key topics include cellular respiration, DNA inheritance, and energy production. These fundamental biology concepts are crucial for medical entrance and state service examinations.

Cell organelles functionsCellular respiration sitesDNA and ribosomesAnimal cell structurePlant cell components

Cell Biology and Structure Questions

Multiple choice botany the world of microbes bacteria - introduction, shape and structure bacteria: types and structure bacteria; benefits and harmful effects non cellular organism : virus world of virus
Correct sequence of layer of bacterial cell envelope from outward to inward is
  1. Cell wall $\rightarrow$ Glycocalyx $\rightarrow$Cell membrane
  2. Cell membrane $\rightarrow$ Glycocalyx $\rightarrow$ Cell wall
  3. Glycocalyx $\rightarrow$ Cell wall $\rightarrow$ Cell membrane
  4. Glycocalyx $\rightarrow$ Cell membrane $\rightarrow$ Cell wall
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Glycocalyx is the outermost layer of the cell envelope. Cell wall lies between plasma membrane and glycocalyx.

So, the correct answer is 'Glycocalyx → Cell wall → Cell membrane'.

Multiple choice botany the world of microbes bacteria - introduction, shape and structure bacteria: types and structure bacteria; benefits and harmful effects non cellular organism : virus world of virus

Which cell organelle is absent in anaerobic bacteria?

  1. Mitochondria

  2. Golgi body

  3. E.R.

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

An anaerobic organism or anaerobic bacteria is any organism that does not require oxygen for growth. It may react negatively or even die if oxygen is present. Mitochondria, Golgi body and ER are organelles of eukaryotic organisms. Since anaerobic bacteria is prokaryotic, they are absent in anaerobic bacteria.

Multiple choice biology control and co-ordination in plants and animals nervous system in animals structure of neuron structure and function of neuron

A nucleated differentiated cell that has lost the power to divide is

  1. Nerve cell

  2. Kidney cell

  3. Liver cell

  4. Leucocytes
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 control and co-ordination in plants and animals nervous system in animals structure of neuron structure and function of neuron

Which cells do not form layer and remain structurally separate?

  1. Epithelial cells

  2. Muscle cells

  3. Nerve cells

  4. Gland cells
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation
A. Epithelial cells form the lining of surface of body. These are present in the external and internal exposed parts of the body. These cells generally rest upon a non cellular supporting layer which is called the basement membrane.
B. Muscle cells are found in the muscles and these are responsible for the movement of the body and various parts. These cells are also called myocytes or sarcocytes.
C. Nerve cells or neurons are the longest cells of the body. These form the structural and functional unit of nervous system. These cells do not form any layer and structurally separate as each neuron has two functional and morphological groups i.e. dendrites and axons.
D. Gland cells are found in various glands of body and are associated with cellular secretion of various substances.
So, the correct answer is 'Nerve cells'.
Multiple choice biology plant and animal tissues nervous system in animals structure of neuron structure and function of neuron

What used to be described as Nissl granules in a nerve cell are now identified as?

  1. Cell metabolites

  2. Fat granules

  3. Ribosomes

  4. Mitochondria
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

A Nissl granule is a large granular body found in neurons. These granules are rough endoplasmic reticulum (RER) with rosettes of free ribosomes and are the site of protein synthesis.

Multiple choice biology plant and animal tissues nervous system in animals structure of neuron structure and function of neuron

Nissl granules are found in 

  1. Liver cells

  2. Nerve cells

  3. Kidney

  4. Heart
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

A Nissl body is also known as Nissl or tigroid substance. It is a large granular body found in neurons. These granules are rough endoplasmic reticulum (RER) with rosettes of free ribosomes and are the sites of protein synthesis.

Multiple choice biology plant and animal tissues nervous system in animals structure of neuron structure and function of neuron

Power of regeneration is lowest in 

  1. Brain cell

  2. Liver cell

  3. Bone cell

  4. Muscle cell
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

The brain is an organ that serves as the center of the nervous system in all vertebrate and most invertebrate animals. In a typical human, the cerebral cortex is estimated to contain 15-33 billion neurons, each connected by synapses to several thousand other neurons. These  neurons communicate with one another by means of long protoplasmic fibers called axons, which carry trains of signal pulses called action potentials to distant parts of the brain or body targeting specific recipient cells. These brain cells are the only cells which do not have the ability to regenerate.

Therefore, the correct answer is option A.

Multiple choice biology plant and animal tissues nervous system in animals structure of neuron structure and function of neuron

Which cell organelle is absent in neuron?

  1. Mitochondria

  2. Ribsomes

  3. Centrioles

  4. Nucleus
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

A centriole is a small set of microtubules arranged in a specific way. There are nine groups of microtubules. When two centrioles are found next to each other, they are usually at right angles. The centrioles are found in pairs and move towards the poles (opposite ends) of the nucleus when it is time for cell division. Neurons cannot divide because they lack centrioles.
Because centrioles function in cell division, the fact that neurons lack these organelles is consistent with the amitotic nature of the cell.

Therefore, the correct answer is option C.

Multiple choice biology plant and animal tissues nervous system in animals structure of neuron structure and function of neuron

Which of the following tissues in mammals show least capacity for regeneration?

  1. Blood

  2. Bone

  3. Nerve

  4. Cartilage
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation
  • The different cells in the body can regenerate in order to replace the damaged or the worn-out cells. 
  • The neurons are one of the brain cells. The cells divide during the embryonal stage. After the birth of a child, the cells lose their capacity to divide. 
  • These cells have the least capacity of regeneration. 
  • Thus, the correct answer is option C. 
Multiple choice biology plant and animal tissues nervous system in animals structure of neuron structure and function of neuron

Choose the odd pair.

  1. Areolar connective tissue - Collagen

  2. Epithelium - Keratin

  3. Muscle fibre - Actin

  4. Neuron - Melanin
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Areolar tissue contains collagen, epithelium contains keratin, and muscle fibers contain actin. Melanin is a pigment found in skin and hair, not a structural protein characteristic of neurons.