Chemical and cellular basis of life Flashcards
(79 cards)
1
Q
Hierarchial organisation of living things
A
Atoms, molecules, organells, cells, tissues, organs, organ-systems, organism, population, community, ecosystem, biosphere
2
Q
No. of naturally occurring elements on the earth’s crust and elements which are essential to continue healthy life and reproduction
A
92 elements naturally occur in earth’s crust. Of which, about 20-25% elements are essential to continue healthy life and reproduction. (about 25- elements are essential for humans and about 17 for plants).
3
Q
C, H, O, N- accounts for of the body mass
A
96.3%
4
Q
Present in small amounts but not trace elements
A
Ca, P, K, S, Na, Cl,
Mg
5
Q
Major properties of water
A
Cohesive behavior
Ability to moderate temperature
Expansion upon freezing
Versatility as a solvent
6
Q
Most abundant group of organic compound on earth is
A
carbohydrates
7
Q
Linear forms of polysaccharides
A
Cellulose , amylose
8
Q
Branched forms of polysaccharides
A
Glycogen, amylopectin, hemicellulose
9
Q
Monomer Inuline
A
Fructose
10
Q
Monomer Pectin
A
Galacturonic acid
11
Q
Monomer Hemicellulose
A
Pentoses
12
Q
Monomer Chitin
A
Glucosamine
13
Q
Proteins elemental composition is
A
C, H,O,N and S
14
Q
2 types of secondary structure of protein
A
alpha helix
beta pleated sheet
15
Q
examples tertiary structure
A
Most of the enzymes
Myoglobin
Albumin
16
Q
examples Quaternary structure
A
Haemoglobin
Collagen
Immunoglobulins
17
Q
Denaturation of proteins
A
Denaturation of protein is the loss of specific chemical three dimensional shape due to the alteration of weak chemical bonds and interactions.
18
Q
Agents affecting the denaturation
A
- High temperature and high energy radiation
- Strong acids, alkaline and high concentrations of salts
- Heavy metals
- Organic solvents and detergents
19
Q
Catalytic protein
A
Pepsin, Amylase
20
Q
Structural protein
A
Keratin
Collagen
21
Q
Storage proteins
A
Ovalbumin
Casein
22
Q
Transport proteins
A
Haemoglobin
Serum albumin
23
Q
Hormones- proteins
A
Insulin
Glucagon
24
Q
Contractile/ Motor
A
Actin/Myosin
25
Defensive proteins
Immunoglobins
26
Functions of DNA
• Store and transmit genetic information from one generation to the next generation
• Store the genetic information for protein synthesis
27
Least abundant type of RNA
Messenger RNA
28
Functions of mRNA
• Copies the genetic information stored in DNA molecule as a sequence of nitrogenous bases
• Transports genetic information from nucleoplasam to the site of protein synthesis (ribosome) through nucleopores
29
Smallest RNA molecule
Transfer RNA
30
Functions of tRNA
transportation of amino acids to the site of protein synthesis
31
most abundant type of RNA
Ribosomal RNA
32
Functions of rRNA
It provides the site where polypeptide chains are assembled.
33
maximum magnification of light microscope is
1000 times the actual size of the specimen
34
resolution power of light microscope is
0.2µm
35
electron microscope should be able to
magnify objects up to
1×10*8 times. In practice, it magnifies just over 5×10*5
times.
36
Diameter of flagella of prokaryotes
20 nm
37
Diameter of flagella of eukaryotes
200 nm
9+2 arrangement of microtubules.
38
Thickness of the plasma membrane
7 nm
39
Difference between animal and plant cell membranes
Plant cell membrane lacks cholesterol
Cholesterol prevents membrane solidification at low temperatures
40
Functions of plasma membrane
Surrounds the cytoplasm physically separating the intercellular structures from the extracellular environment
Regulates the exchange of materials needed for survival
Involves in cell recognition allowing adjacent cells to communicate
Acts as receptor molecules for biochemicals such as hormones, neurotransmitters and immune proteins
Some proteins acts as enzymes while some attach to cytoskeletal fibres
41
Diameter of the nucleus
5 µm
42
Endomembrane system includes
nuclear envelope, the endoplasmic reticulum, the Golgi ap- paratus, lysosomes, various kinds of vesicles and vacuoles, and the plasma membrane.
43
Rough ER functions
• Transport protein synthesized by ribosomes
• Synthesizing glycoproteins
• Produce transport vesicles
• Facilitate the growth of own membrane by adding phospholipids proteins and carbohydrates. Therefore called as membrane factory
44
Smooth ER functions
• It synthesizes lipids including oils, steroids and phospholipids.
• Metabolism of carbohydrates.
• Produce transport vesicles to transport within cell.
• Involves in detoxification.
• Stores Ca2+ ions
45
Golgi apparatus functions
• Collecting, packaging and distribution of materials
• Manufacturing cellulose and non cellulose cell wall components such as pectin
• Produce lysosomes
46
Lysosomes functions
• Digest food particles received by phagocytosis
• Transport residue material out of cell by exocytosis.
• Digest worn out organelles
• Autolysis causing cell death
47
Peroxisome functions
• Detoxification of peroxides
• Photorespiration in plants
48
Glyoxysomes
Specialized type of peroxisome found in fat storing plant cells and converts fatty acids into sugars.
49
Mitochondria functions
• Synthesize ATP in aerobic respiration
• Involve in Photorespiration
50
Components of the cytoskeleton
Microtubules (tubulin polymers)
Microfilaments (actin filaments)
Intermediate filaments
51
Microtubule wall consist of how many columns of tubulin molecules
13
52
The basal body of cillia and flagella has which structure
9+0
53
Functions of cillia and flagella
• Act as locomotor appendages
• Can move fluid over the surface of the tissue
• Cilia lining in oviducts help move an egg toward the uterus
54
Non membrane bounded organelles
Ribosomes
Centrioles
55
Functions of centrioles
• Produce aster and spindle in cell division
Centrioles are absent in plant cells
56
Composition of sap of vacuole
water, ions such as Potassium and Chloride and sometimes water soluble colored pigments such as anthocyanin
57
Composition of stroma of chloroplast
circular DNA (chloroplast DNA), 70s ribosomes, many enzymes, starch granules and lipid droplets
58
Functions of central vacuole
• Stores water and other materials such as sugars, ions and pigments.
• Maintains water balance of the cell
• Gives turgidity and support to cell.
• Produce colours in some plants with sap pigments
• Stores soluble substances needed for cellular activities.
59
Pectins
(magnesium and calcium pectate)
60
pits through which cytoplasm of adjoining cells join through
plasmodesmata.
61
Types of cell junctions and places they are found in
Tight junctions - skin epithelium
Desomosomes/ Anchor junctions - Muscle tissue
Gap junctions/ Communicating junctions - heart muscles and animal embryo
62
Components of the ECM
glycoproteins and other carbohydrates containing molecules secreted by the cells
63
Most abundant glycoprotein in the ECM
Collagen
64
Functions of ECM
• Forms a protective layer over the cell surface
• Linking extra cellular matrix and cytoskeleton.
• Influences the cell behavior by Involving in the mechanical and chemical signaling.
65
Functions of cell wall
Protection and support
Allows development of turgidity when water enters the cell
Prevents bursting of the cell during turgidity
Component of apoplast pathway
Maintains shape of the cell
Limits and control cell growth
Hold the plant up against the force of gravity
66
The collagen fibers are embedded
In a network woven out of proteoglycan
67
Collagen fibers are connected to the integral proteins of the plasma membrane through
Fibronectin
68
Who helped bring the abiotic (nonliving) synthesis of organic compounds into the context of evolution
Stanley Miller
69
Thiol
HS
70
Most of the glucose monomers in starch are linked by
1-4 glycosidic bonds
71
Differences between glucose monomers of starch and cellulose
Glucose monomers of starch are in the alpha configuration while in cellulose it is in beta configuration
72
Phospho-di-ester bonds are formed between
the OH group of the phosphate group and the OH attached to the 3rd carbon of the pentose sugar group
73
Who found out the amino acid sequence of proteins
Frederick Sanger
74
What are chaperone proteins
Proteins that assist the conformational folding or unfolding of large proteins or macromolecular protein complexes
75
Steroids
Characterised by hydrocarbon skeletons consisting of 4 fused rings
Cholesterol is synthesised in the liver
76
Diseases caused by the accumulation of misfolded proteins
Cystic fibrosis
Mad-cow disease
Alzheimer's
Parkinsons
77
Role of microtubules
Maintenance of cell shape
Organelle, chromosome movement
Cell motility as in cilia and flagella
78
Role of actin filaments
Maintenance of cell shape
Cell motility as in pseudopodia
Cytoplasmic streaming
Muscle contraction
Cleavage furrow formation
79
Intermediate filaments
Maintenance of cell shape
Anchorage of nucleus and other cell organelles
Formation of nuclear lamina
