Biology Times (^19)
March
to form glyceraldehyde 3-phosphate. Fatty acids
undergo β-oxidation to reduce acetyl CoA. Acetyl
later enters kreb’s cycle.
24.Sol: Plants require a day length or photoperiod it
was studied by M.W Garner and H. A Allard in
- Short day plants, which flower when the
day length or their flowering is accelerated by a
shorter day length. E.g. Tobacco, Soyabean.
25.Sol: In almost all organisms especially in higher
plants sexual reproduction takes place. It is
usually biparental. Daughter organisms differ
from parents.
26.Sol:The desert grassland whiptail is an all-female
species of reptiles that reproduces by producing
an egg through complete parthenogenesis
i.e.Obligatory parthenogenesis.
27.Sol: Flowers with exposed stigma and anther are
called chasmogamous flower.
28.Sol: Conceptual
29.Sol: Conceptual
30.Sol: A gene deletion or deletion mutation is
a mutation where a part of chromosome or a
DNA sequence is removed or lost during DNA
replicaion. So, before a deletion occurred , the
gene sequence was ABCDEF, now after the loss
of a DNA sequence(i.e., C) it is , ABDEF.
31.Sol: It produces four types of ascospores in
Neurospora - two of one parental type , two of
some other parental type ,two of one recombinant
and next two of second recombinant type.
32.Sol: Erythroblastosis foetalis is hemolytic anemia
in the fetus which is caused by transplacental
transmission of maternal Rh antibodies to foetal
RBCs. The disorder normally concludes from
inconsistency between maternal and foetal blood
groups, frequently Rh0(D) antigens.
33.Sol: In Escherichia coli, the transport and
metabolism of lactose is done by operon. The lac
operon of E. coli has genes associated in lactose
metabolism. This happens only when glucose is
absent and lactose is present.
34.Sol:The experiment conducted by Meselson
and Stahl using E. coli bacteria as a model
system exhibited that DNA replicated semi-
conservatively, that means each strand in a DNA
molecule aids as a design for synthesis of a new,
complementary strand.
35.Sol:The DNA segment participating in
transcription is called transcription unit. It starts
from TATA box (a promoter) and completes in
stop codon (a terminator).
36.Sol: During the translocation process of the
elongation phase of protein synthesis , the
mRNA is ahead of one codon, and is paired for
movement of tRNA from the ribosomal A-site
(i.e., aminoacyl) to P-site (i.e., peptidyl) and from
P to E (exit ) sites , in a sequence catalyzed by
elongation factor EF-G.
37.Sol: P. notatum is replaced by P. chrysogenum due
to less yield of Pencillin antibiotic, so it is used in
recent era.
38.Sol: Roqueforte cheese employs Penicillium
roquefortii for ripening.
39.Sol: Pseudomonas Sps is a genetically engineered
Microorganism for Bioremediation of oil spills.
40.Sol: Conceptual
41.Sol: Taq Polymerase have thermostable property
as the bacteria from which its extracted also
contains such property.
42.Sol: Cloning gene is a process where fragments
of DNA are transferred from one organism to
another usually carried on a DNA vector
43.Sol: In 1983, Eli Lily an American Company first
prepared two DNA sequences corresponding to
A and B chains of human insulin and introduced
them in plasmids of Escherichia coli to produce
insulin chains. Chains A and B were produced
separately extracted and combined by creating
disulfide bonds to form human insulin( Humulin).
44.Sol: Isinglass is a substance obtained from the dried
swim bladders of fish; it is a form of collagen used
mainly for the clarification or fining of some beer,
vinegar and wine.
45.Sol: Haploid culture produces homozygous plants,
it is for improvements of plants in plant breeding
programmes.