(i) Based oil the position of centromere, chromosomes are called telocentric (terminal centromere), Acrocentric (terminal centromere capped by telomere), Sub metacentric (centromere subterminal) and Metacentric (centromere median).
(ii) The eukaryotic chromosomes may be rod shaped (telocentric and acrocentric), L-shaped (sub-metacentric) and V-shaped (metacentric).

(i) Grana (singular: Granum) are formed when many of these thylakoids are stacked together like pile of coins.
(ii) Light is absorbed and converted into chemical energy in the granum, which is used in stroma to prepare carbohydrates. Thylakoid contain chlorophyll pigments.
(iii) The chloroplast contains osmophilic granules, 70s ribosomes, DNA (circular and non histone) and RNA.
(iv) These chloroplast genome encodes approximately 30 proteins involved in photosynthesis including the components of photosystem I & II, cytochrome bf complex and ATP synthase.
(v) One of the subunits of Rubisco is encoded by chloroplast DNA.
(vi) It is the major protein component of chloroplast stroma, single most abundant protein on earth.
(vii) The thylakoid contain small, rounded photosynthetic units called quantosomes.
(viii) It is a semi-autonomous organelle and divides by fission.

(i) Offers definite shape and rigidity to the cell.
(ii) Serves as barrier for several molecules to enter the cells.
(iii) Provides protection to the internal protoplasm against mechanical injury.
(iv) Prevents the bursting of cells by maintaining the osmotic pressure.
(v) Plays a major role by acting as a mechanism of defense for the cells.

During endocytosis the cell membrane infolds around the material to form a vacuole and brings it into cytoplasm. There are two types of endocytosis:
1.Phagocytosis - Solid Particles are engulfed by membrane, which folds around it and forms a vesicle. The enzymes digest the material and products are absorbed by cytoplasm.
2.Pinocytosis - Fluid droplets are engulfed by membrane, by forming vesicles around them.

1. In the year 1966, scientist Dodge and his coworkers proposed another kind of organisms called mesokaryotes. These organisms shares some of the characters of both prokaryotes and eukaryotes.
2. These contains well organized nucleus with nuclear membrane and the DNA is organized like karyotes are absent and they histone protein components divide through amitosis similar with prokaryotes. Eg: Protozoa like Noctiluca, some phytoplanktons.

The cell wall plays a vital role in holding several important functions given below
1. Offers definite shape and rigidity to the cell.
2. Serves as barrier for several molecules to enter the cells.
3. Provides protection to the internal protoplasm against mechanical injury.
4. Prevents the bursting of cells by maintaining the osmotic pressure.
5. Plays a major role by acting as a mechanism of defense for the cells.

1. Occur free in the cytoplasm.
2. Attached to Endoplasmic Reticulum.
3. Inside Mitochondria.
4. Inside Chloroplast.

1. Glyoxysome is a single membrane bound organelle.
2. It is a sub cellular organelle and contains enzymes of glyoxylate pathway.
3. β-oxidation of fatty acid occurs in glyoxysomes of germinating seeds Eg: Castor seeds.

S.no Prokaryotes Eukaryotes 1 It is unicellular It is unicellular and Multicellular 2 Many prokaryotes contain a single circular chromosome Eukaryotes contain multiple linear chromosomes 3 Prokaryotic chromosomes are condensed in the nucleoid via DNA super coiling Eukaryotic chromosomes are condensed in membrane bound nucleus via histones 4 In prokaryotes transcription and translation occur simultaneously in the cytoplasm In eukaryotes transcription occurs in nucleus and translation occurs in cytoplasm 5 Most prokaryotes contain only one copy of each gene that is they are haploid Most eukaryotes contain two copies of each gene that is they are diploid 6 Extra chromosomal DNA (i.e.) plasmids are present Eg: Bacteria Plasmids are absent. Eg: Plant cell, Animal cell

The colloidal protoplasm which is in gel form can change into sol form by solation and the sol can change into gel by gelation.