Select the correct statement regarding reproduction
Mating in dogs is synchronised with lunar cycle.
Salamanders always have internal fertilisation.
In Trygon, the male introduces sperms into female through a modified pelvic fin.
Catla has internal fertilisation
Which form of reproduction is correctly matched?
Euglena transverse binary fission
Paramecium longitudinal binary fission
Amoeba multiple fission
Plasmodium binary fission
Assertion: Many plants are propagated vegetatively even though they bear seeds.
Reason: Potatoes multiply by tubers and apple by cutting.
If both assertion and reason are true and reason is the correct explanation of assertion
If both assertion and reason are true but reason is not the correct explanation of assertion
If assertion is true but reason is false
If both assertion and reason are false.
Division in a bacterial cell is carried out through
multiple fission
binary fission
budding
plasmotomy
Which of the following two hormones are essential for induced breeding of fishes?
TSH and ACTH
Oestrogen and progesterone
FSH and LH
Vasopressin and oxytocin
Product of sexual reproduction generally generates
longer viability of seeds
prolonged dormancy
new genetic combination leading to variation
large biomass
Which of the following processes was discovered by Lederberg and Tatum (1946)?
Transduction
Transformation
Asexual reproduction
Conjugation
The component of bacteria that retains the crystal violet stain during Gram staining is
O- antigen
lipopolysaccharide
peptidoglycan
cytoplasmic membrane
C.
peptidoglycan
Gram staining is the method of differentiating bacterial species into two large groups, i.e., Gram positive and Gram negative bacteria based on the physical properties of their cell walls.
In the process of Gram staining
- alcohol is used for decolourlisation process. It solubilises lipid but does not solubilise peptidoglycan layer.
As Gram positive bacteria has less lipid percentage as compared to peptidoglycan. Thus, peptidoglycan which does not get solubilised retain the Gram stain and Gram negative bacteria which has thinner peptidoglycan layer cannot retain the Gram stain.