Chapter-8 Cell Structure and Functions - Extra Questions

  1.  Indicate whether the following statements are True (T) or False (F).

  1. Unicellular organisms have one-celled body. (T/F)

  2. Muscle cells are branched. (T/F)

  3. The basic living unit of an organism is an organ. (T/F)

  4. Amoeba has irregular shape. (T/F)

Explanation:

  1. True

  2. False

  3. False

  4. True


2. Make a sketch of the human nerve cell. What function do nerve cells perform?

Explanation:

Human Nerve cell

The primary role of the nerve cell is to carry signals from sensory tissues to the brain and vice versa. It has influence over how various body components function.


3.

  1.  Write short notes on the following.

  1. Cytoplasm

  2. Nucleus of a cell

Explanation:

  1. Cytoplasm

Cytoplasm is the name for the liquid that makes up cells. It includes other cells floating in the cytosol along with filaments, ions, proteins, and macromolecular structures. However, recent findings imply that the conventional meaning of cytoplasm is no longer accurate. It was thought to be a fluid-like material decades ago, but recent research shows that it is more like liquids that make glass. With the exception of the nucleus, the cytoplasm in living cells is associated with the components of the cell. Prokaryotic cells, however, lack a distinct nucleus wall and instead store their genetic material in their cytoplasm. The cells are more compact and have a simpler structure of the cytoplasm than eukaryotes.


  1. Nucleus of a Cell

Nucleus: An organelle with DNA instructions has been referred to by the nucleus, which also directs other organelles for cellular functions.

Atomic components include:

  • The core is divided into the following four sections.

  • nuclear lining

  • Nucleoplasm, or nuclear secretion

  • Nucleolus

  • Chromosomes

             Functions 

  • It preserves hereditary data in the shape of DNA and RNA.

  • In the nucleus, fresh DNA is created, which is necessary for cell growth.

  • Stimulates the production of RNA, which in turn stimulates the creation of proteins; it has a nucleolus, which is where ribosomes are made.

  • It permits only specific particles and compounds to pass through nuclear openings.


4.Which part of the cell contains organelles?

Explanation:


The cytoplasm of the cell contains the floating components of the cell. Between the cell wall and the nucleus, there is a gel-like material called cytoplasm. The cytoplasm of a cell contains a number of additional parts, or organelles. These include ribosomes, Golgi structures, mitochondria, and more.


5.Make sketches of animal and plant cells. State the differences between them.

Explanation:

 

Plant cell

Animal cell

They are very big.

Smaller than plant cells

Cell membrane is visible.

There is no cell exterior.

The vacuoles are big.

The vacuoles are tiny.

Plastids were visible.

Plastids could not be seen in mammal cells, with the exception of Euglena.


Animal and plant cell


6.State the difference between eukaryotes and prokaryotes.

Explanation:


Prokaryotes

Eukaryotes

Most of them have only one cell.

They are primarily complex.

No nuclear barrier exists. The core is therefore vaguely described.

A nuclear barrier exists. The centre is thus clearly delineated.

There are not all of the cell's components.

There are all of the cell's components.

There is no nucleolus.

There is a nucleolus.

For example, blue-green algae, Bacteria

For example, plants, animal cells and fungi.


7.Where are chromosomes found in a cell? State their function.

Explanation:


Genes are carried by chromosomes, which are thread-like structures found in the cytoplasm. The chromosomes contain every piece of information needed for passing traits from one generation to the next. Only because of chromosomes is it feasible for traits to be inherited.


8.“Cells are the basic structural units of living organisms”. Explain

Explanation:


 Cells make up a variety of parts of vegetation and creatures. It can perform all living tasks and is the smallest element of existence. They serve as the basis for existence. Because of this, cells are referred to as "the fundamental structural and functional building blocks of life."

There are many different types of cells that carry out a variety of functions.

Their proportions and designs correspond to the tasks they carry out.


9.Explain why chloroplasts are found only in plant cells.

Explanation:


Only because chloroplasts contain chlorophyll, which is necessary for photosynthesis, are chloroplasts discovered in plant cells.

Through the process of photosynthesis, chlorophyll captures sunlight and uses it to produce sustenance for plants.

Chloroplasts are plastids that are only found in plant cells because they are necessary for the food-producing process known as photosynthesis.


10.Complete the crossword with the help of the clues given below

Across

1. This is necessary for photosynthesis.

3. Term for component present in the cytoplasm.

6. The living substance in the cell.

8. Units of inheritance present on the chromosomes.

Down

1. Green plastids.

2. Formed by a collection of tissues.

4. It separates the contents of the cell from the surrounding medium.

5. Empty structure in the cytoplasm.

7. A group of cells.


Crossword Puzzle on Cell-Structure and Functions-1


Across

  1. Chlorophyll

  2. Organelle

  3. Protoplasm

  4. Genes

 Down

  1. Chloroplast

  2. Organ

  3. Membrane

  4. Vacuole

  5. Tissue

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