Samacheer Kalvi 6th Science Solutions Term 2 Chapter 5 The Cell

Samacheer Kalvi 6th Science Solutions Term 2 Chapter 5 The Cell

Tamilnadu Samacheer Kalvi 6th Science Solutions Term 2 Chapter 5 The Cell

Samacheer Kalvi 6th Science The Cell Textual Evaluation

I. Choose the appropriate answer:

Samacheer Kalvi 6th Science Term 2 Question 1.
The unit of measurement used for expressing dimension (size) of cell is
(a) centimeter
(b) millimeter
(c) micrometer
(d) meter
Answer:
(c) micrometer

Samacheer Kalvi Guru 6th Science Question 2.
Under the microscope Priya observes a cell that has a cell wall and distinct nucleus. The cell that she observed is
(a) a plant cell
(b) an animal cell
(c) a nerve cell
(d) a bacteria cell
Answer:
(a) a plant cell

Kalvi Guru 6th Science Question 3.
A control centre’ of the eukaryotic cell is
(a) Cell wall
(b) Nucleus
(c) Vacuoles
(d) Chloroplast
Answer:
(b) Nucleus

Samacheer Kalvi 6th Standard Science Question 4.
Which one of the following is not an unicellular organism?
(a) Yeast
(b) Amoeba
(c) Spirogyra
(d) Bacteria
Answer:
(c) Spirogyra

Science Term 2 Question 5.
Most organelles in a eukaryotic cell are found in the
(a) Cell wall
(b) cytoplasm
(c) nucleus
(d) Vacuole
Answer:
(b) cytoplasm

II. Fill in the Blanks:

1. The instrument used to observe the cell is _______
2. I control the food production of a cell. Who am I? _______
3. I am like a policeman. Who am I _______ ?
4. The Term “ cell” was coined by _______
5. The egg of an Ostrich is the _______ single cell.

Answers:

1. microscope
2. chloroplast
3. cell wall
4. Robert hooke
5. largest

III. True or False. If False, give the correct answer:

Samacheer Kalvi.Guru 6th Science Question 1.
A cell is the smallest unit of life.
Answer:
True

Question 2.
Nerve cell is the longest cell.
Answer:
True

Question 3.
Prokaryotes were the first form of life on earth.
Ans:
True

Question 4.
The organelles of both plants and animals are made up of cells.
Answer:
True

Question 5.
New cells are produced from existing cells.
Answer:
True

IV. Match the following:

Answer:

V. Arrange in a correct sequence:

Question 1.
Elephant, Cow, Bacteria, Mango, Rose plant.
Answer:
Bacteria, Rose plant, Mango, Cow, Elephant.

Question 2.
Hen egg, Ostrich egg, Insect egg.
Answer:
Insect egg, Hen egg, Ostrich egg.

VI. Analogy:

Question 1.
Prokaryote : Bacteria :: Eukaryote : _______
Answer:
Plant or animal cell.

Question 2.
Spirogyra : Plant cell:: Amoeba :
Answer:
animal cell.

Question 3.
Food producer : Chloroplasts :: Power house _______
Answer:
mitochondria.

VII. Give very short answer:

Question 1.
Who discovered the cell in 1665?
Answer:
The English scientist Robert Hooke discovered the cell in 1665 from cork slices kept under a microscope.

Question 2.
What type of cells do we have?
Answer:
We have Eukaryotic cells.

Question 3.
What are the essential components of a cell?
Answer:
A typical cell consists of three major parts.

1. An outer cell membrane
2. A liquid cytoplasm
3. Nucleus

Question 4.
What are the organelles found only in plant cell?
Answer:
Chloroplasts and cell wall are the organelles found only in plant cell.

Question 5.
Give any three examples of the eukaryotic cell?
Answer:

1. Plant cells
2. Animal cells
3. Most of fungi and Algae

Question 6.
Which one is called as “Area of movement”?
Answer:
Cytoplasm is called as “Area of movement”.

Question 7.
Shiva said “ Bigger onion has larger cells when compared to the cells of smaller onion”! Do you agree with his statement or not ? Explain Why?
Answer:
No, the big onion and small onion both of them have plant cell and the size of every cell remains same whether it is of a small onion or big one. The shape is larger means that the number of cells is more in bigger onion.

VIII. Give short answer:

Question 1.
Why cells are called building blocks of life?
Answer:
A brick is a basic building block of a wall, likewise, the cells are the basic structural and functional unit of every living organism. So the cells are called as building blocks of life.

Question 2.
Identify any four parts of the Plant cell.

Question 3.
Distinguish between prokaryotic and eukaryotic cells.
Answer:
Prokaryotic cell:

1. It’s diameter ranges from 1 to 2 micron
2. Absence of membrane bound organelles
3. Nucleus consisting of no nuclear membrane
4. Absence of nucleoli

Eukaryotic cell:

1. It’s diameter ranges from 10 to 100 micron
2. Presence of membrane bound organelles
3. True nucleus consisting of nuclear membrane
4. Presence of nucleoli

Question 4.
Make sketches of animal and plant cells which you observe under microscope.
Answer:
Plant cell:

1. It is usually larger in size. It is hard in nature.
2. Plant cell have a cell wall in addition to their cell membrane.
3. Plant cell have chloroplast which contain chlorophyll
4. Plant cells have large vacuoles. Centrioles are absent.

Animal cell:

1. Animal cells are generally smaller than plant cells. It is not so hard as plant cell.
2. A cell wall is absent.
3. Chloroplast is usually absent.
4. An animal cell may have many small vacuoles.
5. Centrioles are found in animal cells.

Question 5.
Write about the contribution of Robert Hooke in cell biology.
Answer:
Robert hooke was a scientist and inventor. He improved microscope and built a compound microscope. One day he made thin sections of the cork and observed many small identical chambers through his microscope. They were hexagonal in shape. Based on this observations Hooke published a book named Micrographia in the year 1665, where he first used the term Cell. He describes the structure of tissue using the term cell.

IX. Answer in detail:

Question 1.
Tabulate any five cell organelles and their function.
Answer:

Question 2.
Draw a neat labelled diagram of a prokaryotic cell.
Answer:

X. Project:

1. Use your imagination and create 3-D model of a plant cell?
2. You can use numerous food materials such as a jelly and some cake to make a cell body. Cell organelles can be made using nuts and dry fruits. You can display the model in your class room and invite teachers or students from other classes to rise questions on the project and try to give answer.
Answer:
Activities to be done by the students themselves

Samacheer Kalvi 6th Science The Cell Intext Activities

Activity 1

Aim:
To observe the structure of a single cell (Hen’s egg).

Materials Needed: A hen’s egg and a plate.

Method: Crack the shell and break open the egg in a plate.

Observation: The egg has a yellow part and a transparent part surrounding it. The white transparent part (albumin) is jelly-like and represents the cell’s cytoplasm, while the yellow part (yolk) is thicker and represents the cell’s nucleus. On the internal side of the shell can be seen a thin membrane- like structure, which represents the cell membrane.

Activity 2

Aim: To observe onion peel cells under a microscope

Materials Required: Glass slide, cover slip, onion, iodine solution, knife and microscope.

Procedure: Take an onion and cut it into two halves along its length. Take out one of its fleshy leaves. With the help of a pair of forceps, remove a transparent, thin peel from the inner surface of the leaf. Take a glass slide and put a drop of water at the centre. Place the peel on the drop of water. Pour a drop of iodine solution on the peel. Now place a cover slip over the material. Observe under the microscope.

Observation: You will be able to see rectangular cells of the onion peel, with a nucleus in each of them.

Activity 3

Aim: To rectify the variation between 2-D shape and 3-D shape.

Material req uired: Polythene bag, water, marble ball (golli gundu)

Procedure: Take a polythene bag with water. Put a marble ball into the polythene bag. Then draw a picture in your note book about this task. If you draw a picture in round shape. It will be called 2-Dimenstional picture. If you draw a picture in spherical shape it is called 3-dimenstional.

Result: Now you understand your misconceptions. So the animal cells are spherical in shape and structure, not in a round shape.

Samacheer Kalvi 6th Science The Cell Additional Questions

I. Choose the correct answer:

Question 1.
Which one is prokaryotic cell among the following?
(a) Plant cell
(b) Animal cell
(c) Nerve cell
(d) Cyano bacteria cell
Answer:
(d) Cyano bacteria cell

Question 2.
The habitat of Eschericia coli bacteria is
(a) It is a soil inhabiting bacteria
(b)It lives in human intestine
(c) It is an aquatic bacteria
(d) It lives in the air
Answer:
(b) It lives in human intestine

Question 3.
A typical cell consists of ______ major parts
(a) Two
(b) Four
(c) Three
(d) Five
Answer:
(c) Three

Question 4.
The central yellow coloured yolk of egg is
(a) cytoplasm
(b) cell membrane
(c) Reserve material
(d) Nucleus
Answer:
(d) Nucleus

Question 5.
Approximate number of cells in the human body is ______
(a) 3.7 × 10¹³
(c) 3.7 × 10¹⁴
(b) 3.7 × 10¹²
(d) 3.7 × 10¹⁵
Answer:
(a) 3.7 × 10¹³

Question 6.
Prokaryotic cell type of nucleus is called as _______
(a) nucleolus
(b) nuclear membrane
(c) organelles
(d) nucleiod
Answer:
(d) uncleiod

II. Fill in the blanks:

1. _______ is the basic structural and functional unit of every living organism.
2. Now a days an _______ microscope is used to magnify the cells
3. In Latin the word ‘cellula’ means a _______
4. The branch of science that deals with the study of cells is called.
5. The outer covering part of cell is called _______
6. _______ cells were the first form of life on earth.
7. _______ is present in plant cell only.
8. Plants prepared food with the help of _______

Answers:

1. Cell
2. electron
3. small chamber
4. cell biology
5. cell membrane
6. Prokaryotic
7. Chloro plant
8. chlorophyll

III. Find whether the following sentences are true or false. If false Correct the statement:

Question 1.
The cell is self-sufficient carry out all the fundamental and essential functions of an organism.
Answer:
True.

Question 2.
Robert Hooke saw many objects like Butterfly’s compound eyes, Bee’s wings etc.
Answer:
False. Robert Hooke saw many objects like Butterfly’s wings, Bees compand eyes etc.

Question 3.
All the cells can be seen with our naked eye.
Answer:
False. All the cells cannot be seen with our naked eye.

Question 4.
The size of the bacterial cell ranges from 0.01 micro meter to 0.5 micrometer.
Answer:
True.

Question 5.
Spirogyra and Human beings are unicellular.
Answer:
False. Spirogyra and Human beings are multicellular.

IV. Matching:

Answer:

1. – c
2. – e
3. – b
4. – a
5. – d

V. Analogy

Question 1.
Smallest cell: virus.
Biggest cell: _______
Answer:
Ostrich egg

Question 2.
Unicellular organism : Chlamydomonas.
Multi cellular organism : _______
Answer:
Human beings

Question 3.
No true nucleus : Prokaryotic cell.
True nucleus : _______
Answer:
Eukaryotic cell

Question 4.
Plant cell: Chloroplast.
Animal cell: _______
Answer:
Centrioles

VI. Give short answer

Question 1.
Give two examples of prokaryotic cell?
Answer:
Cyano bacteria and Eschericia coli bacteria are the examples of prokaryotic cell.

Question 2.
What are the two types of cell?
Answer:
Cells are classified into two types. First one is Prokaryotic cell. It has no true nucleus. Another one is Eukaryotic cell. It has true nucleus.

Question 3.
Define: Prokaryotic cells.
Answer:

1. It has No true nucleus.
2. This type of nucleus is called as nucleiod.
3. No nuclear membrane is around the nucleiod.
4. It is ranging from 0.003 to 2.0 micro meter in diameter.

Question 4.
Write about chloroplasts.
Answer:

1. It is found in plant cell only.
2. It contains green pigment chlorophyll.
3. It captures the energy of sunlight and uses it to produce food for the photosynthesis.
4. it is called as producers for the cell.

Question 5.
What are the functions of nucleus.
Answer:

1. It acts as brain of the cell.
2. It regulates and controls all the cell activities.

Question 6.
Cell wall is called as supporter or protector. Why?
Answer:

1. It surrounds and protects the cell.
2. It makes the cell stiff and strong.
3. It is called as supporter or protector.

VII. Answer in detail:

Question 1.
Write the characteristics of plant cell with diagram.
Answer:
Plant cell:

1. It is usually larger in size. It is hard in nature.
2. plane cell have a cell wall in addition to their cell membrane
   
3. Plant cell have chloroplast which contain chlorophyll
4. Plant cells have large vacuoles. Centrioles are absent.

Question 2.
Write the characteristics of animal cell with diagram.
Answer:
Animal cell:

1. Animal cells are generally smaller than plant cells. It is not so hard as plant cell.
2. A cell wall is absent.
3. Chloroplast is usually absent
   
4. An animal cell may have many small vacuoles.
5. Centrioles are found in animal cells.

Question 3.
Draw the 3-dimensional cell structure and label the parts.
Answer:
Question 4.
Give the difference between animal cell and plant cell.
Answer:
Animal cell:

1. Animal cells are generally smaller than plant cells. It is not so hard as plant cell.
2. A cell wall is absent.
3. Chloroplast is usually absent.
4. An animal cell may have many small vacuoles.

Plant cell:

1. It is usually larger in size. It is hard in nature.
2. Plant cell have a cell wall in addition to their cell membrane.
3. Plant cell haves chloroplast which contain chlorophyll
4. Plant cells have large vacuoles. Centrioles are absent.