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1. Choose currect option
A. Growth of cell wall during cell 
elongation take place by ………….
 a. Apposition
 b. Intussusception
 c. Both a & b 
 d. Super position

B. Cell Membrane is composed of
 a. Proteins and cellulose
 b. Proteins and Phospholipid
 c. Proteins and carbohydrates
 d. Proteins, Phospholipid and some 
 carbohydrates

C. Plasma membrane is Fluid structure due to presence of 
 a. Carbohydrates
 b. Lipid
 c. Glycoprotein
 d. Polysaccharide

D. Cell Wall is present in 
 a. Plant cell 
 b. Prokaryotic cell
 c. Algal cell
 d. All of the above

E. Plasma membrane is
 a. Selectively permeable
 b. Permeable
 c. Impermeable
 d. Semipermeable

F. Mitochondria DNA is
 a. Naked
 b. Circular
 c. Double stranded
 d. All of the above

G. Lysosomes are not help full in
 a. Osteogenesis
 b. Cellular digestion
 c. Metamorphosis
 d. Lipogenesis

H. Which of the following set of organelles 
contain DNA
 a. Mitochondria, Peroxysome
 b. Plasma membrane, ribosome
 c. Mitochondria, chloroplast 
 d. Chloroplast, dictyosome

I. Golgi body is absent in
a. Prokaryotes
b. Mature mammalian RBC
c. Alkaryotes
d. All of the above

2. Answer the following questions
A. Plants have no circulatory system? 
Then how cells manage intercellular 
transport?
Answer : Plants have no circulatory system yet they manage to circulate water and minerals for their needs with the help of special tissues. Transportation of water takes place through the process of diffusion and osmosis, which depend upon the gradient.

Diffusion – when the molecule move from high concentration to low concentration in random direction for short distance.

Osmosis – When the molecules move from its region of higher chemical potential to its region of lower chemical potential.

Imbibition–  It is special type of diffusion when water is absorbed by solids colloid and causing them increase in size or volume. eg: absoption of water by seeds.

Intracellular transport by apoplast pathway and symplast pathway in the adjacent cells or plasmodesmata.

Uptake of mineral ions and water through phloem and xylem {specialised tissue) . Flow through xylem is is unidirectional ,upward while that of phyloem is bi- directional, upward and downward.

B. Is nucleolus covered by membrane?
Answer : The nucleolus is a round body located inside the nucleus of a eukaryotic cell. It is not surrounded by a membrane but sits in the nucleus. The nucleolus makes ribosomal subunits from proteins and ribosomal RNA, also known as rRNA.

C. Fluid mosaic model proposed by Singer and Nicolson replaced Sandwich model proposed by Danielli and Davson? 
Why?
Answer : It was replaced by sandwich model as Fluid Mosaic Model only describes the characteristics of cell membrane from upper view.It explains that proteins are like ice bergs floating on sea of lipids. But sandwich model gives detail explanation about the arrangement of lipids and proteins.

D. The RBC surface normally shows 
glycoprotein molecules. When determining blood group do they play 
any role?
Answer : The glycoproteins( carbohydrate+ protein) present on the surface of RBC molecules serve as markers or surface antigens and help in determining the blood group of an individual. The ABO blood grouping is actually based on the presence of these glycoproteins.

E. How cytoplasm differs from nucleoplasm in chemical composition?
Answer : Though the cytoplasm is found in each known cell, nucleoplasm is only found in eukaryotic cells. The main difference between cytoplasm and nucleoplasm is that cytoplasm is a fluid mass of the cell which is composed of cell organelles whereas nucleoplasm is the sap of the nucleus which contains the nucleolus

3. Answer the following questions
A. Distinguish between smooth and rough endoplasmic reticulum.
Answer : The difference between the rough endoplasmic reticulum and the smooth endoplasmic reticulum is that the rough endoplasmic reticulum contains ribosomes. The smooth endoplasmic reticulum does not contain ribosomes. The ribosomes are what give rough endoplasmic reticulum its characteristic “roughness.”

SER do not have ribosomes but RER have ribosomes. SER mainly produce and export lipids and protein and function for detoxification, while RER produces, secrete and export proteins and few hormones.

B. Mitochondria are power house of cell. 
Give reason.
Answer : Mitochondria are cell organelles present in the eukaryotic cells. They are involved in the cellular respiration. They releases energy from food. They generate energy rich molecules, ATP from cellular respiration which is later used for other process. Hence, mitochondria are called as the powerhouses of the cell.

C. What are types of plastids?
Answer : There are four main types of plastids:
Chloroplasts.
Chromoplasts.
Gerontoplasts.
and Leucoplasts.

4. Label the diagrams and write down the details of concept in your word

Answer :

5. Label the A, B, C, and D in above diagram and write the functions of organells A and B 

 Answer :

7. Identify each cell structures or organelle  from it’s description below.
i. Manufactares ribosomes
Answer : nucleus

ii. Carrys out photosynthesis
Answer : chloroplast

iii. Can bud of vesicles, which form the golgi apparatus.
Answer : Endoplasmic Reticulum

iv. Manufactures ATP in animal and plant cells.
Answer : Mitochondria

v. Selectivelly permeable.
Answer : plasma membrane

8. Onion cells have no chloroplast. How can we tell they are plants?
Answer : Though onion cells have no chloroplast, they are still classified as plants as onions grow under the soil and they do not need to participate in photosynthesis, rather they use their bulb as a means of storing energy and nutrients.