List of top Biology Questions

Describe the Species-Area relationship as observed by Alexander von Humboldt, for a wide variety of taxa in nature.
Write the location and function of fimbriae in human female.
Explain the beneficial role of the following, produced as a result of the processes of biotechnology, to mankind:
(α) −1−antitrypsin
Name and explain the role of inner and middle walls of the human female uterus.
Explain the beneficial role of the following, produced as a result of the processes of biotechnology, to mankind:
Cow named Rosie
Explain the biological treatment of the major part of the sludge transferred from the large aeration tank into the anaerobic sludge digesters before its final release into the natural water bodies.
What do you mean by activated sludge in an STP?
State any two criteria for determining biodiversity hotspots
Name the type of heterogamety observed in most birds.
Alien species are highly invasive and are a threat to indigenous species. Substantiate this statement with the help of any two examples.
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
Which two main inflammation-causing chemicals are produced by the mast cells in such an immune response?
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.
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:
Human Immunodeficiency Virus is a member of the group of viruses known as:
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:
Inheritance of which of the following traits is shown in the cross given below?

Autosomal recessive trait

Choose the correct option from the following:
In a DNA, the percentage of thymine is 20. What is the percentage of guanine in it?