worksheet of cell

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Name :			_________________________________	Subject:	Biology
Class :			IX	Month :	April
THE FUNDAMENTAL UNIT OF LIFE
		SECTION A
1		Floating around the cytoplasm are small structures called organelles. Like the organs in
		Your own body, each one carries out a specific function necessary for the cell to survive.
		Imagine the cell as a miniature city. The organelles might represent companies, places,
		or parts of the city because they each have similar jobs. Below are the descriptions of
		important parts of the Cell City.
	A	City Limits- controls what goes into and out of a city.
	B	Road/Highway system- allows for movement throughout the city.
	C	City Hall- controls the activities of the city.
	D	City Auditor - stores all of the records of the city and passes them on as the city grows.
	E	City Planning Office- a place in city hall where plans are made for the construction of the
		city.
	F	Construction Company- builds structures for the city.
	G	Post Office/ Shipping Company- packages, modifies, sorts, and delivers products and
		materials throughout the city.
	H	Grocery Stores, Shopping Centers, Garbage Dump site, Lakes,- store foods, water and
		wastes.
	I	Waste treatment center or Food Processing Plant- Breaks down waste into useful
		material or processes large quantities of food entering the city into smaller packages that
		can be used more easily.
	J	Power Company- produces energy for the city.
	K	Solar Power Plant- uses the sun’s energy to produce power for the city.
	L	Parks, grass, trees- fills the space between structures in a city and gives a city its shape
		As you move through this worksheet, see if you can match the important parts
		of the city listed above to the specific organelles found in cells. Be sure to write neatly,
		and in complete sentences.
	i)	The nucleus is a large, round/oval structure usually located near the center of the cell. It is the control center for all activities of the cell.
	a)	What company or place does the nucleus resemble in a Cell City?
	b)	Why do you think so?
	ii)	The cell membrane is a thin, flexible envelope that surrounds the cell. It allows the cell to
		change shape and controls what goes into and out of the cell.
	a)	What company or place does the cell membrane resemble in a Cell City?
	b)	Why do you think so?
	iii)	The endoplasmic reticulum consists of a network of tube-like passageways that proteins from the ribosomes and fats are transported through. a) What company or place does the endoplasmic reticulum resemble in a Cell City? b) Why do you think so?
	a)
	b)
	iv)	The ribosomes are small grain-like bodies made mostly of RNA and produced in the nucleolus. Proteins are constructed at the ribosomes. a) What company or place do the ribosomes resemble in a Cell City? b) Why do you think so?
	a)
	b)
	v)	The nucleolus is a small, dense object found in the middle of the nucleolus. It makes the RNA and ribosomes for the cell. a) What company or place does the nucleolus resemble in a Cell City? b) Why do you think so?
	a)
	b)
	vi)	The jelly-like area between the nucleus and the cell membrane is called the cytoplasm. It fills the space between the nucleus and the cell membrane. a) What company or place does the cytoplasm resemble in a Cell City? b) Why do you think so?
	a)
	b)
	vii)	The mitochondria are tiny bean-shaped structures in the cytoplasm with a smooth outer membrane, and a greatly folded inner membrane. They supply the energy for the cell by transforming sugars into energy. a) What company or place do the mitochondria resemble in a Cell City? b) Why do you think so?
	a)
	b)
	viii)	The chromosomes are rod-shaped bodies found in the nucleus. They are made of DNA and protein. They contain all the information to run the cell. They also pass on the hereditary traits of the cell to new cells. a) What company or place do the chromosomes resemble in a Cell City? b) Why do you think so?
	a)
	b)
	ix)	The chloroplast is an oval, green structure found in the cytoplasm. It contains chlorophyll. It captures the sun’s energy and uses it to produce sugars in a process called photosynthesis. a) What company or place do the chloroplasts resemble in a Cell City? b) Why do you think so?
	a)
	b)
		The lysosomes are small round structures found in the cytoplasm. They contain digestive enzymes that break down large food particles into sugars and other simple substances. a) What company or place do the lysosomes resemble in a Cell City? b) Why do you think so?
	a)
	b)
	xi)	The vacuole is a large, round sac found in the cytoplasm. It stores water, food, wastes, or other materials needed by the cell. a) What company or place does the vacuole resemble in a Cell City? b) Why do you think so?
	a)
	b)
	xii)	The Golgi apparatus modifies, sorts, and packages proteins and other materials for storage in the cell or secretion outside the cell. a) What company or place doe the Golgi apparatus resemble in a Cell City? b) Why do you think so?
		SECTION B
		Choose the correct alternative:
1.		Gaseous exchange in cells takes place by
	a	Osmosis
	b	Oxocytosis
	c	Diffusion
	d	Endocytosis
2.		A cell may swell up and even burst if
	a	The concentration of water molecules within the cell is higher than the concentration of water molecules in the surrounding medium
	b	The concentration of water molecules in the surrounding medium is higher than  the concentration  of water molecules within the cell
	c	The concentration of water molecules is same in the cell and in the surrounding Medium
	d	It is a plant cell and surrounded by a hypotonic solution.
3.		Chromosomes are made up of
	a	DNA and Protein
	b	RNA and Protein
	c	DNA and RNA
	d	Protein
4.		The process of plasmolysis in plant cell may be defined as
	a	Breakdown / bursting of plasma membrane in a hypotonic medium
	b	Shrinkage of cytoplasm in hypertonic medium
	c	Breakdown / bursting of plasma membrane in a hypertonic medium
	d	Shrinkage of cytoplasm in hypotonic medium
5.		Amoeba acquires its food through a process known as
	a	Endocytosis
	b	Exocytosis
	c	Plasmolysis
	d	both exocytosis & endocytosis
6.		Prokaryotes have an undefined nuclear region which is known as
	a	Nucleus
	b	Nucleoid
	c	Nucleolus
	d	Nucleic acid
7.		A cell organelle that is not surrounded by a membrane is
	a	Golgi apparatus
	b	Ribosome
	c	Chloroplast
	d	Endoplasmic reticulum
8.		Which of the following is not a function of cell wall?
	a	provides structural strength
	b	enable the cells to withstand greater changes in surrounding medium than animal cells
	c	permits the cells to withstand very dilute (hypotonic) external media without bursting
	d	enable the cells to exchange gases and minerals
9.		Which of the following is a common feature of mitochondria and plastids?
	a	Presence of DNA and Ribosomes
	b	Ability to produce ATP
	c	Deeply folded inner membrane
	d	Presence of matrix called stroma
10.		Which cell organelle is actively involved in membrane biogenesis?
	a	ER
	b	Golgi Apparatus
	c	Lysosomes
	d	Vacuoles
		SECTION C
1		Ribosomes are called the protein factories of the cell. Give reason.
2		Endoplasmic system is known as the endoskeleton system of the cell. Justify.
3
	a	Identify the cell organelle.
	b	Label the parts 1 to 4.
4		Why does i) spinach look green ii) papaya yellow and iii) edible part of water melon red?
5		Name two cell organelles, which contain their own genetic material.
6		Lysosomes are known as suicidal bags. Give reason.
7		Name the cell organelle present only in animal cell. Write its function.
8		Why do plant cells possess large sized vacuole?
9		In brief state what happens when Golgi apparatus is removed from the cell.
10		Draw an animal cell and label the parts which
	a	determine function and development of the cell.
	b	is called as power house of the cell.
	c	packages materials coming from the endoplasmic reticulum.
	d	is a fluid contained inside the nucleus.
11		2   4   5   6   3   1
	a	Name the parts labelled 1 to 6
	b	Is the given diagram that of a plant cell or an animal cell?
	c	Mention three evidences visible in the diagram to support the answer given in (b)
	d	Mention any two functions of the part labelled as 6
12		Why does the skin of your fingers shrink when you wash clothes for a long time?
13		Why is endocytosis found in animals only?
14		Name cell organelles having double membrane envelope.
15		What will happen if human red blood cells are placed in (a) hypertonic solution and (b) hypotonic solution?
16		When compared to one another, solutions are classified as hypertonic, hypotonic or isotonic. First research the meaning of these terms, and then decide whether an IV you might receive in the hospital should be hypertonic, hypotonic or isotonic to your blood. Defend your choice.
17		Which part of a cell are concerned with the following:
	a	Liberation of energy - __________________
	b	Trapping of solar energy-____________________
	c	Synthesis of proteins  - _______________
	d	Transmission of characters from parents to offspring.-______________
	e	Removal of dead and worn out cells and foreign bodies -____________
18		Explain why chromosomes are one of the chief components of a nucleus. Which two organelles of a cell contain its own genetic material? What will happen if the organisation of a cell is destroyed due to some physical or chemical influence.
19		Why does nuclear membrane have pores?
20		Why do chromosomes contain DNA in the nucleus?
21		Give 2 roles of nucleus in the cell.
22		How does smooth endoplasmic reticulum differ from rough endoplasmic reticulum?       (3 points)
23		What do you understand by “membrane bio genesis?”
24		What is cell theory? Name the scientist who presented it.
25		What is plasmolysis? Give its one example.
		SECTION C
1.		Given below is an incomplete flow-chart on cell organelles. Some boxes/ spaces in the flow-chart have been left blank. Complete the flow-chart adding terms / names/ functions as and where required
2.		Given below are the diagrams representing a plant cell and an animal cell. Label any five organelles common in plant cell and animal cell.
3.		Complete the following table based on the characteristics and functions of cellular structures.
		Cell organelle Characteristics One important function i) Consist of large amount of RNA and enzymes ii) Consist of coloring pigments iii)  Synthesis of respiratory enzymes iv) Network of tubular membrane system throughout the cytoplasm v) Lysosmes
		Question Bank
1		Name the organelle which is associated with protein synthesis.
2		Which organelle of plant cell has chlorophyll pigment in it?
3		Name the cell organelles in which the following cell organelles are present. a)    Cisternae                   (b) stroma
4		Give the full form of ATP.
5		Distinguish between plant cell and animal cell.
6		Name the different types of plastids. Give the function of each type.
7		Write down the major differences between prokaryotic cells and eukaryotic cells.
8		Define the terms protoplasm, cytoplasm and nucleoplasm.
9		What is the difference between plasma membrane and cell wall? Give the functions of each one.
10		Which organelle is the powerhouse of the cell? Write about its functions briefly.
11		Draw labeled diagrams of the following cell organelles and write down their functions: (a)  Mitochondria                                         (b) Golgi apparatus (b)  Endoplasmic reticulum
12		Give reason: Chloroplasts are called the “kitchens” of the cell.
13		Distinguish between the following:
	a	Vacuoles and granules
	b	Chloroplast and chlorophyll
	c	Cytoplasm and nucleoplasm
	d	Centrosome and centrioles
14		What is osmosis? What are its types? What happens to a cell when it is placed in hypotonic, isotonic and hypertonic solutions respectively ? State two points of differences between osmosis and diffusion.
15		Draw a well labelled diagram of an animal cell.
16		Name the following:
	a	The organelle that contains powerful digestive enzymes
	b	The organelle that has its own DNA
	c	The organelle that forms cytoplasmic framework
	d	The organelle that helps in expelling excess water in amoeba
17		Name the scientist who first described Golgi apparatus. What is a cistern?
18		Give any three points of difference between prokaryotic and Eukaryotic cell.
19		What would happen to the life of a cell if there was no Golgi apparatus
20		Who invented Microscope? Who coined the word ‘cell’?
		The End