List of practice Questions

Alien species are highly invasive and are a threat to indigenous species. Substantiate this statement with the help of any two examples.
What do you mean by activated sludge in an STP?
State any two criteria for determining biodiversity hotspots
If the birds have 18 pairs of autosomal chromosomes and a pair of sex chromosomes, fill in the blanks (i), (ii), (iii) and (iv) in the table given below. (Use symbols Z and W for sex chromosomes).
18 pairs of autosomal chromosomes
Name the type of heterogamety observed in most birds.
Many children in the metro cities are suffering from a very common exaggerated response of the immune system to certain weak antigens in the air. (i) What is the term used for the above mentioned disease?
Name the main type of antibody produced by the immune system in response to this disease.
Which two main inflammation-causing chemicals are produced by the mast cells in such an immune response?
What is the term used for the milk produced during the initial days of lactation?
Explain why the milk produced by the mother during the initial days of lactation is considered to be very essential for the newborn infant.
Why are restrictions imposed on MTP in India? Up to how many weeks or trimesters, is MTP considered relatively safe for a female, if necessary to perform, by a medical practitioner?
Expand PID. Name any two common viral infections transmitted through sexual contact in human females.
Arrange the given important steps of decomposition in their correct order of occurrence in the breakdown of complex organic matter and explain the fourth step in the process.
\( \fbox{Catabolism}\) \(\fbox{Leaching} \fbox{Fragmentation} \fbox{Mineralisation} \fbox{Humification}\)
Assertion (A): In some species of asteraceae and grasses, seeds are formed without fertilization.
Reason (R): Formation of fruit without fertilization is called parthenocarpy.
Assertion (A): Isolated single cells can be fused to produce somatic hybrids.
Reason (R): Cells selected for somatic hybridisation have desirable characters.
Assertion (A): In humans, filariasis is characterized by inflammation of the lower limbs.
Reason (R): Filarial worm usually lives in the lymphatic vessels of the lower limbs.
Bacteria growing anaerobically on cellulosic material produce large amounts of which gases? Select the correct option.
The animals that evolved into the first amphibians during evolutionary history were:
Select the statements that are true for the embryo of the flowering plants from the given options:
1. The zygote forms a proembryo and subsequently heart-shaped, globular and mature embryo.
2. Most zygotes divide to form embryo only after a certain amount of endosperm is formed.
3. The embryo develops at the micropylar end of the embryo sac.
4. A typical dicotyledonous embryo consists of an embryonal axis and a scutellum.
Choose the correct option from the following:
In a DNA, the percentage of thymine is 20. What is the percentage of guanine in it?
Inheritance of which of the following traits is shown in the cross given below?

Autosomal recessive trait

Choose the correct option from the following:
Human Immunodeficiency Virus is a member of the group of viruses known as:
Given below are few statements with reference to the human male reproductive system:
1. Paired seminal vesicles, prostate gland and bulbourethral gland constitute the male accessory glands.
2. Secretions of the male accessory glands constitute the seminal plasma.
3. Secretions of the bulbourethral glands help in the lubrication of the penis.
4. Enlarged end of the the penis is known as foreskin.
5. Seminal plasma is rich in fructose, calcium and certain enzymes.
Choose the option with all true statements from the given options:
If a natural population of 60 individuals is in Hardy-Weinberg equilibrium for a gene with two alleles B and b, with the gene frequency of allele B of 0.7, the genotype frequency of Bb will be:
Some of the important goals of HGP are given below. Choose the correct goal of HGP.