Cell the Unit of Life
Exam Duration: 45 Mins Total Questions : 30
The highest number of mitochondria are in
- (a)
parenchyma cells
- (b)
sieve tubes
- (c)
meristematic tissues
- (d)
None of these
Which of the following statements is correct?
- (a)
Ribosomes do not contain DNA
- (b)
Eukaryotic 80 S ribosomes break into 50 S and 30 S
- (c)
Plasmodesmata are found as intercellular junction between animal cells
- (d)
Ribosomes were discovered by Beadle and Tatum
The hydrophilic nature of DNA is due to the presence of
- (a)
deoxyribose sugar
- (b)
phosphate group
- (c)
thymine base
- (d)
number of hydrogen bonds
Protein can be denautured by
- (a)
carbon dioxide
- (b)
carbon monoxide
- (c)
heat
- (d)
oxygen
Who was awarded Nobel Prize for the synthesis of RNA?
- (a)
A Kornberg
- (b)
H Khorana
- (c)
Nirenberg
- (d)
S Ochoa
The term 'primary structure of proteins' refers to
- (a)
sequence of amino acids
- (b)
overall conformation
- (c)
subunit interaction
- (d)
All of the above
The nucleolus is the site of formation of
- (a)
spindle fibres
- (b)
chromosomes
- (c)
ribosomes
- (d)
peroxisomes
Nucleolus forms ribosomal subunits by wrapping the rRNA with ribosomal proteins.The ribosomal subunits later leave nucleus through the nuclear pores.
A homopolymer has only one type of building block called monomer repeated 'n' number of times. A heteropolymer has more than one type of monomer. Proteins are heteropolymers usually made of
- (a)
20 types of monomers
- (b)
40 types of monomers
- (c)
3 types of monomers
- (d)
only 1 type of monomer
The function and shape of a protein is affected by sequence of 20 types of amino acids, each having an amino group -NH2, a carboxylic acid group -COOH, a hydrogen atom each attached to carbon located next to -COOH group and a side chain R which varies from one amino acid to other. (It can be hydrogen or an aliphatic group, an aromatic or heterocyclic group).
Synaptonemal complex is formed during
- (a)
pachytene
- (b)
leptotene
- (c)
zygotene
- (d)
diakinesis
The esoskeletons of arthropods have a complex polysaccharide called
- (a)
Starch
- (b)
Cellulose
- (c)
Chitin
- (d)
Pectin
The chemically distinct components of a nucleotide is/are
- (a)
a heterocyclic compound
- (b)
a monosaccharide
- (c)
a phosphoric acid
- (d)
all the above
is the mast abundant protein in animal world,
- (a)
Collagen
- (b)
RuBisca
- (c)
Cysteine
- (d)
Insulin
Phytochrom is a
- (a)
flavoprotein
- (b)
glycoprotein
- (c)
lipoprotein
- (d)
chromoprotein
The simplest amino acid is
- (a)
Glycine
- (b)
Proline
- (c)
Leucine
- (d)
Tryptophan
The major portion of the dry weight of plants comprises of
- (a)
carbon. nitrogen and hydrogen
- (b)
carbon, hydrogen and oxygen
- (c)
nitrogen, phosphorus and potassium
- (d)
calcium, magnesium and sulphur
The major portion of the dry weight of plants comprises carbon, nitrogen, oxygen, hydrogen.These are also called as framework elements.
One of the similarities between DNA and RNA is that both
- (a)
are polymers of nucleotides
- (b)
are capable of replicating
- (c)
have similar sugars
- (d)
have similar pyrimidine bases
DNA Composition | RNA Composition |
---|---|
Deoxyribose sugar. | Ribose sugar |
Adenine, guanine (both purine) and cytosine, thymine (both pyrimidine), nitrogenous bases. | Adenine, guanine (both purine) and uracil, cytosine (both pyrimidine) nitrogenous bases |
Phosphate molecules. | Phosphate molecules |
It is polymer of nucleotides. | It is also polymer of nucleotides. |
It is capable to replicate in all cases because it functions as heredity material | It is formed from DNA by the process of transcription only in few cases (RNA viruses) it functions as heredity material. |
The four elements making 99% of living system are?
- (a)
CHOS
- (b)
CHOP
- (c)
CHON
- (d)
CNOP
Carbon, hydrogen, oxygen and nitrogen are called as big four of the cell. C is 18%, 0 is 65%, H is 10% and N is 2.5%. These are principal non-metal elements and form 95% of total cellular materials
Addition of new cell wall particles amongst the existing ones is
- (a)
deposition
- (b)
apposition
- (c)
intussusception
- (d)
aggregation
Opposition or accretion is defined as the addition of new cell wall particles amongst the existing one, such as deposition of secondary walls in layers from outside over the existing primary wall.
Intussusception can be demonstrated as the internal growth of the primary wall which occurs during the growth period of the cell resulting in the increase in volume of cell wall.
Deposition Molecules settling out of a solution.
Aggregation Direct mutual attraction between particles or Aggregation of soil granules to form soil structure
Match column I with column II and select the correct option from the given codes.
Column I | Column II | ||
---|---|---|---|
A. | Division of nucleus | (i) | Interphase |
B. | Division of cytoplasm | (ii) | Cytokinesis |
C. | DNA replication | (iii) | Syncytium |
D. | Karyokinesis not followed by cytokinesis | (iv) |
Karyokinesis |
- (a)
A-(ii), B-(iv), C-(i), D-(iii)
- (b)
A-(iv), B-(ii), C-(i), D-(iii)
- (c)
A-(iv), B-(ii), C(iii), D-(i)
- (d)
A-(iii), B-(ii), C-(iv), D-(i)
What does A represent in the given diagram of a nucleotide?
- (a)
Glycosidic bond
- (b)
Phosphate bond
- (c)
Ester bond
- (d)
Ionic bond
Which of the following is correct regarding the given figure?
- (a)
Number of pairs of homologous chromosomes Number of chromatids Number of centromeres 3 6 12 - (b)
Number of pairs of homologous chromosomes Number of chromatids Number of centromeres 3 12 6 - (c)
Number of pairs of homologous chromosomes Number of chromatids Number of centromeres 6 6 12 - (d)
Number of pairs of homologous chromosomes Number of chromatids Number of centromeres 6 12 6
Which of the following reactions is not enzyme-mediated in biological system?
- (a)
Dissolving CO2 in water
- (b)
Unwinding the two strands of DNA
- (c)
Hydrolysis of sucrose
- (d)
Formation of peptide bond
Dissolving CO2 in water does not require any enzyme. CO2 has higher solubility in water than O2. Solubility of CO2 in water can be increased with decrease in temperature, a principle used in carbonated drinks.
At anaphase - II of melosis each chromosome contains ;
- (a)
4 DNA
- (b)
3 - DNA
- (c)
2 - DNA
- (d)
1 - DNA
Sugar found in haemolymph of insects is called-
- (a)
Maltose
- (b)
Lactose
- (c)
Trehalose
- (d)
Galactose
Histone is a basic protein due to -
- (a)
Alanine & glycine
- (b)
Methionine & serine
- (c)
Tryptophan & tyrosine
- (d)
Lysine & Arginine
Circular and double stranded DNA occurs in -
- (a)
Golgibody
- (b)
Mitochondria
- (c)
Nucleus
- (d)
ER
Michaelis constant (km) value of enzyme is substrate concentration at which velocity of reaction is
- (a)
Vmax
- (b)
One third Vmax
- (c)
Half V max
- (d)
One fifth Vmax
If an enzyme has been given the EC code 5.2.1.7, it is likely to be involved in
- (a)
Digestion
- (b)
Redox reaction
- (c)
isomerization
- (d)
Molecular breakdown
_____phase synthesizes enzymes required during S phase.
- (a)
G2
- (b)
M
- (c)
S
- (d)
G1
Cytokinesis in a plant cell is achived by the foemation of cell plate instead of cleavage furrow, which is formed in
- (a)
Centripetal manner
- (b)
Centrifugal manner
- (c)
Both centripetal and centrifugal manner
- (d)
Equational manner