Search for notes by fellow students, in your own course and all over the country.
Browse our notes for titles which look like what you need, you can preview any of the notes via a sample of the contents. After you're happy these are the notes you're after simply pop them into your shopping cart.
Title: cell biology
Description: contains key points about the cell and its organelles
Description: contains key points about the cell and its organelles
Document Preview
Extracts from the notes are below, to see the PDF you'll receive please use the links above
Cell-The Unit of Life
(1) Cytology: (G
...
kyios = cell ; logas = study) is the branch of biology which comprises the study of cell structure
and function
...
(3) There are two types of cells: plant cell and animal cell
...
Cell wall absent
...
Nucleus present near the centre
...
fibres
...
Plastids are absent
...
Generally tubular in shape
...
Many vacuoles occur, which are smaller in size
...
Number of mitochondria is approximately 1600 – 16000 in liver
cells
...
method
...
vitamins
...
Contractile vacuole may occur to pump excess water
...
Tissue fluid containing sodium chloride bathes the animal cells
...
Generally much smaller than 100 micrometer
Spindle formed during cell division is anastral
...
Lysosomes present in less number
...
Chromosomes are larger in size
...
(4) Difference between Prokaryotic and eukaryotic cells
Prokaryotic cell
Eukaryotic cell
It is a single membrane system
...
Cell wall surrounds the plasma membrane
...
Animal cell lack it
...
Strengthening material is
It is composed of polysaccharide
...
in fungi & cellulose in others plants
...
It lacks respiratory enzymes
...
g
...
body etc
...
Ribosomes are 80 S type
...
Cytoplasm show streaming movements
...
Endocytosis and exocytosis occur in animal cells
...
Mitotic spindle is formed in cell division
...
The mRNA needs processing
...
Nucleus is distinct from
directly in cytoplasm
...
cytoplasm
...
Nuclear DNA is linear and associated with histone proteins
extranuclear DNA is circular and protein free
...
Replication of DNA occurs during S- Phase of cell cycle only
...
5 to 10 micrometer) and have much
These are relatively large (10 – 15 micrometer) and have much
less DNA
...
Sexual reproduction absent but parasexuality present
...
Plasmids and pili occur in many prokaryotes
There are no plasmids and pili in eukaryotic cells
Example – E
...
Cell division is typically mitotic
...
Mesosome
Absent
which take part in respiration
(5) Difference between primary cell wall and secondary cell wall
Primary cell wall
Secondary cell wall
Primary wall is laid inner to middle lamella
Secondary wall is laid inner to primary wall
...
It is formed when the cells have stopped growing
...
Extensibility is absent except in collenchyma cells
...
It is three or more layered
...
Cellulose content is comparatively high (20 – 90%)
...
They are longer, closely arranged straight and parallel
...
Protein content up to 1%
...
It is 25% of the total
...
Lipid is absent
...
Intrinsic Protein
These lie throughout phospholipid matrix and project on both
surfaces, also called transmembrane or tunnel protein
...
They form about 70% of total membrane proteins
...
mitochondria
...
(2) Cell wall is the outer most, rigid, protective, non living and supportive layer found in all the plant cells,
bacteria, cyanobacteria and some protists
...
(4) Difference between primary cell wall and secondary cell wall
Primary cell wall
Secondary cell wall
Primary wall is laid inner to middle lamella
Secondary wall is laid inner to primary wall
...
It is formed when the cells have stopped growing
...
Extensibility is absent except in collenchyma cells
...
It is three or more layered
...
Cellulose content is comparatively high (20 – 90%)
...
They are longer, closely arranged straight and parallel
...
Protein content up to 1%
...
It is 25% of the total
...
Lipid is absent
...
(2) It is quasi fluid in nature
...
(4) A cell wall lies external to plasmalemma in plant cells, many monerans, some protists and fungal cells
...
(6) They are collectively called biomembranes
...
Nageli and C
...
(8) It was replaced by the term plasmalemma or plasma membrane by Plowe (1931)
...
It is selectively or
differentially permeable
...
(3) Discoveries
(i) J
...
(ii) Dujardin (1835) discovered it and called them “sarcode”
...
(iv) Hugo Von Mohl (1844) gave the significance of it
...
Cytoplasm
The substance occurs around the nucleus and inside the plasma membrane containing various organelles and
inclusions is called cytoplasm
...
(2) These are absent in all prokaryotes like bacteria and cyanobacteria
...
(4) they synthesize ATP (adenosine triphosphates) which is energy currency of every cell
...
(2) These are largest cell organelles in plant cell
...
(4) Difference between chlorophyll a and b
Chl
...
b
Absorption peak at 430, 662
...
Bluish green in colour
...
Soluble in petroleum, ether
...
Present in all green plants excepts autotrophic bacteria
...
In chloroplast it is 75%
...
a shows blood red colour while in transmitted
In reflected light it show dull brown colour while in transmitted
light, it shows blue green colour
...
Endoplasmic Reticulum
(1) Definition: It is well developed electron microscopic network of interconnected cisternae, tubules and vesicles
present throughout the cytoplasm, especially in the endoplasm
...
The ER was first noted by Porter,
Claude, and Fullman in 1945 as a network
...
(3) 2 type of ER are found in cells:
Smooth ER- characterized with absence of ribososme on its surface , it is involved in synthesis of lipids
Rough ER- it shows ribosomes attached to its surface , function is to synthesize protein
Golgi Complex
(1) Definition: Golgi complex is made up of various membranous system e
...
cisternae, vesicles and vacuoles
...
(3) Discovery: Discovery: First observed by George (1867) but it’s morphological details were given by Camillo
Golgi (1898), in nerve cells of barn fowl and cat
(4) cis face is receptive face receiving unprocessed proteins from ER
(5) Trans face is the exporting face of golgi , it transport processed propteins to the target sites
Title: cell biology
Description: contains key points about the cell and its organelles
Description: contains key points about the cell and its organelles