Which one of the following biomolecules is correctly characterised?
1. | Palmitic acid - an unsaturated fatty acid with 18 carbon atoms |
2. | Adenylic acid - adenosine with a glucose phosphate molecule |
3. | Alanine amino acid - Contains an amino group and an acidic group anywhere in the molecule |
4. | Lecithin - a phosphorylated glyceride found in the cell membrane |
For its action, nitrogenase requires:
1. Light
2. Mn2+
3. Super oxygen radicals
4. High input of energy
Tobacco plants resistant to a nematode have been developed by the introduction of DNA that produced (in the host cells):
1. A particular hormone
2. An antifeedant
3. A toxic protein
4. Both sense and anti-sense RNA
Where do certain symbiotic microorganisms typically occur in the human body?
1. Oral lining and tongue surface
2. Vermiform appendix and rectum
3. Duodenum
4. Caecum
Identify the meiotic stage in which the homologous chromosomes separate while the sister chromatids remain associated at their centromeres.
1. Metaphase-II
2. Anaphase-I
3. Anaphase-II
4. Metaphase-I
Which one of the following cellular parts is correctly described?
1. | Centrioles - sites for active RNA synthesis |
2. | Ribosomes - those on chloroplasts are larger (80s) while those in the cytoplasm are smaller (70s) |
3. | Lysosomes - optimally active at a pH of about 8.5 |
4. | Thylakoids - flattened membranous sacs forming the grana of chloroplasts |
Cuscuta is an example of:
1. Brood parasitism
2. Predation
3. Endoparasitism
4. Ectoparasitism
The supportive skeletal structures in the human external ears and the nose tip are examples of:
1. Areolar tissue
2. Bone
3. Cartilage
4. Ligament
Read the following five statements (I - V) and answer as asked next to them.
I. | In Equisetum, the female gametophyte is retained on the parent sporophyte |
II. | In Ginkgo, male gametophyte is not independent |
III. | The sporophyte in Riccia is more developed than that in Polytrichum |
IV. | Sexual reproduction in Volvox is isogamous |
V. | The spores of slime molds lack cell walls |
How many of the above statements are correct?
1. Three | 2. Four |
3. One | 4. Two |
Identify the molecules (a) and (b) shown below and select the right option giving their source and use.
(I) | |
(II) |
Molecule |
Source |
Use |
|
1. |
(II) Heroin |
Cannabis sativa |
Depressant and slows down body functions |
2. |
(II) Cannabinoid |
Atropa belladonna |
Produces hallucination |
3. |
(I) Morphine |
Papaver somniferum |
Sedative and painkiller |
4. |
(I) Cocaine |
Erythroxylum coca |
Accelerates the transport of dopamine |