Biology Today - May 2018

FERTILISATION Fertilisation is the fusion of male and female gametes. In seed plants, i.e., gymnosperms and angiosperms the mal ...

In contrast, true fruits develop only from the ovary. In few species, fruits develop without fertilisation. Such fruits are cal ...

Ectopic pregnancy is a condition of (a) inflammation of cervix during pregnancy (b) implantation of embryo in the oviduct rathe ...

DDT residues are rapidly passed through food chain causing biomagnification because DDT is (a) water soluble (b) lipid soluble ...

The first transgenic animal for food production is (a) ALV-resistant chicken (b) Tracy (c) Rainbow trout (d) Transgenic salmon. ...

Which of the following period is known as the age of fishes? (a) Ordovician period (b) Silurian period (c) Devonian period (d) ...

Which of the following bacteria is not associated with denitrification? (a) Nitrocystis (b) Pseudomonas (c) Thiobacillus (d) Mi ...

(i) (ii) (iii) (iv) (a) Cortisol Steroid Polypeptide Estradiol (b) Insulin Protein Polypeptide Epinephrine (c) Cortisol Protein ...

Tensor tympani and stapedius muscles are present in (a) external ear (b) middle ear (c) inner ear (d) cochlea and utriculus. Wh ...

(a) Cholesterol – A component of animal cell membrane (b) Lecithin – A component of cell membrane (c) Triglyceride – An energy s ...

The anther wall consists of four wall layers where (a) tapetum lies just inner to endothecium (b) middle layers lie between end ...

SECTION - A How do cytokine barriers provide innate immunity in humans? Write the dual purpose served by deoxyribonucleoside tr ...

(a) “India has greater ecosystem diversity than Norway”. Do you agree with the statement? Give reasons in support of your answe ...

They act as substrates i.e., nucleotides for the replication process as well as provide energy for the polymerisation of nucleot ...

(b) (i) Wings of butterfly and birds show analogy as the basic structure of the wings of the insects is different from the wings ...

In case of birds, the type of sex determination is ZW-ZZ type. Female has two different sex chromosomes (AA + ZW) whereas male ...

found in the colon bacteria Escherichia coli, recognises the base sequence GAATTC in DNA duplex and cuts its strands between G a ...

(iii) A poster making programme can be held in school depicting the causes, effects and solutions for air pollution. The student ...

Select the number of plants out of the following in which haplodiplontic life cycle is present. Ulothrix, Fucus, Riccia, Selagi ...

Which test is used to diagnose coronary artery disease (CAD)? (a) Electrocardiogram (b) Cardiac catheterisation (c) Treadmill s ...