Cell- The basic unit of life

Question 1

the main arena for all activities to take place within the cell.

Answer 1

Cytoplasm

Question 2

What are the cell organelles found in both eukaryotic and prokaryotic cells?

Answer 2

Ribosomes (no cell membrane)

Question 3

Non membrane bound cell organelle present in animals which helps in cell division

Answer 3

Centriole

Question 4

The smallest cells are

Answer 4

Mycoplasma

Question 5

Largest isolated cells are

Answer 5

Ostrich eggs

Question 6

Longest human cells are

Answer 6

Nerve cells

Question 7

Only prokaryotes without a cell wall

Answer 7

Mycoplasma

Question 8

The small DNA which are present in prokaryotes? What function do they perform

Answer 8

Plasmids-confer special phenotypic characters to the individual organisms. eg. resistance against antibiotics

Question 9

Define Mesosomes

Answer 9

Infoldings or invaginations from the cell membrane into the cell.

Question 10

Name the types of mesosomes

Answer 10

Vesicles, Tubules and lamellae

Question 11

The cell wall in prokaryotes is made of how many layers

Answer 11

3- they are the glycocalyx, cell wall and the cell membrane

Question 12

Give one function of the cell wall in prokaryotes

Answer 12

Gives shape and support, protects the cell and prevents it from bursting or collapsing in unfavourable conditions

Question 13

Give some functions of mesosomes

Answer 13

cellular respiration, DNA replication and distribution to daughter cells, secretion processes, increases the surface area of the cell membrane

Question 14

Chromatophores are present in

Answer 14

Cyanobacteria; contain pigments

Question 15

The non- membranous cell organelle in animal cells except for ribosomes

Answer 15

centroid- helps in cell division

Question 16

Ribosomes are associated with the……………….. of the cell

Answer 16

plasma membrane

Question 17

What is the type of ribosome present in prokaryotes

Answer 17

70s which is made up of two sub units- 50s and 30s

Question 18

Define polysomes

Answer 18

Several ribosomes attach to a single mRNA and form long chains of polysomes and polyribosomes.

Question 19

Gas vacuoles are present in

Answer 19

Blue-green algae and purple and green bacteria

Question 20

Give the composition of cell membrane

Answer 20

Phospholipids and cholesterol, proteins and carbohydrates

Question 21

The ratio of proteins and lipids in human erythrocytes is

Answer 21

52% proteins and 40% lipids

Question 22

Differentiate between the two types of proteins based on the ease of extraction

Answer 22

Integral proteins are buried partially or completely into the cell membrane while peripheral proteins lie on the surface

Question 23

Fluid MosAIC MODEL WAS GIVEN BY

Answer 23

Singer and Nicholson

Question 24

State the fluid mosaic model

Answer 24

THE QUASI FLUID NATURE OF THE LIPIDS ALLOWS THE LATERAL MOVEMENT OF PROTEINS ALONG THE OVERALL BILAYER. THIS MOVEMENT IS MEASURED AS ITS FLUIDITY.

Question 25

fluid nature of the plasma membrane is important for

Answer 25

endocytosis, cell growth, cell division, formation of intercellular junctions and secretion

Question 26

The algal cell wall is made of

Answer 26

mannans, galactans, cellulose and calcium carbonate

Question 27

The plant cell wall is made of

Answer 27

Cellulose, hemicellulose, proteins and pectins

Question 28

Cell wall in eukaryotes helps in

Answer 28

Gives shape and support to the cell, allows the cell to cell interactions, the barrier to undesirable macromolecules, protects the cell from mechanical damage and infection

Question 29

Middle lamella is made of

Answer 29

Calcium pectate

Question 30

Middle lamella is used in

Answer 30

glueing the neighbouring cells together

Question 31

Plasmodesmata is?

Answer 31

Connects the cytoplasms of different cells together

Question 32

The Endomembrane system is composed of

Answer 32

ER, Golgi apparatus, Lysosome, vacuoles

Question 33

define the ER

Answer 33

a network or reticulum of tubules that lie scattered in the cytoplasm of the cell

Question 34

The Er divides the intracellular space into

Answer 34

Luminal and extraluminal compartments

Question 35

....................... is present in the cells which are actively involved in secretions and synthesis.

Answer 35

RER

Question 36

Secretion of steroidal hormones in animal cells is done by

Answer 36

SER

Question 37

Define Golgi apparatus

Answer 37

Many flat disc-shaped structures or cisternae which are arranged parallel to each other

Question 38

The COnvex face is called

Answer 38

Cis face

Question 39

Golgi apparatus main function is

Answer 39

Packaging materials and sending them to intra cellular targets or outside the cell

Question 40

What are synthesised in the golgi apparatus

Answer 40

glycolipids and glycoproteins