______ is a seasonal breeder.

(a)

Poultry

(b)

Honey bees

(c)

Deers

(d)

Rabbit

Identify the correct statements from the following.

(a)

Chlamydiasis is a viral disease

(b)

Gonorrhoea is caused by a spirochaete bacterium, Treponema palladium

(c)

The incubation period for syphilis is 2 to 14 days in males and 7 to 21 days in females

(d)

Both syphilis and gonorrhoea are easily cured with antibiotics

Which is NOT a part of transcription unit?

(a)

Promoter

(b)

Operator

(c)

Structural gene

(d)

Terminator

The Neanderthal man had the brain capacity of

(a)

650 – 800cc

(b)

1200cc

(c)

900cc

(d)

1400cc

What gases are produced in anaerobic sludge digesters?

(a)

Methane and CO₂ only

(b)

Methane, hydrogen sulphide and CO₂

(c)

Methane, hydrogen sulphide and O₂

(d)

Hydrogen sulphide and CO₂

Which of the following is correct for r-selected species

(a)

Large number of progeny with small size

(b)

large number of progeny with large size

(c)

small number of progeny with small size

(d)

small number of progeny with large size

Van't Hoffs rule describes the impact of ____________ on the environment.

(a)

Light

(b)

Temperature

(c)

Water

(d)

Soil

In monoecious plants,

(a)

Both autogamy and geitonogamy are prevented

(b)

Both autogamy and geitonogamy are takes place

(c)

Autogamy takes place preventing geitonogamy

(d)

Autogamy is prevented whereas geitonogamy takes place

Due to incomplete linkage in maize, the ratio of parental and recombinants are ______.

(a)

50:50

(b)

7:1:1:7

(c)

96.4: 3.6

(d)

1:7:7:1

Statement 1: Pairing of homologous chromosome is called as syndesis.
Statement 2: Proterminal synapsis occurs from telomeres.

(a)

Statement 1 is correct and Statement 2 is incorrect

(b)

Statement 1 is incorrect and Statement 2 is correct

(c)

Both the statements are correct

(d)

Both the statements are incorrect

The time duration for sterilization process by using autoclave is ______ minutes and the temperature is ______.

(a)

10 to 30 minutes and 125° C

(b)

15 to 30 minutes and 121° C

(c)

15 to 20 minutes and 125° C

(d)

10 to 20 minutes and 121° C

The ideal soil for Cultivation is:

(a)

Loamy soil

(b)

Clayey soil

(c)

Sandy soil

(d)

Silt soil

Which one of the following is not a functional unit of an ecosystem?

(a)

Productivity

(b)

Stratification

(c)

Energy flow

(d)

Decomposition

Assertion (A): Ozone acts as a natural sunblock.
Reason (R): UV rays reaching the earth are deviated from earth.

(a)

A is correct R is incorrect.

(b)

A is incorrect R is correct.

(c)

R explains A.

(d)

Both A and R are incorrect.

The only cereal that has originated and domesticated from the New world.

(a)

Oryza sativa

(b)

Triticum asetumn

(c)

Triticum duram

(d)

Zea mays

Define Vivipary.

How is polyspermy avoided in humans?

State the allelic forms of I gene and mention its chromosomal location.

What is a replication fork?

Differentiate between infectious and non-infections disease.

Why are some organisms called as eurythermals and some others as stenohaline ?

Discuss the gross primary productivity is more efficient than net primary productivity.

What is toddy?

How does immune system work?

Rearrange the descent in human evolution
Austrolopithecus → Homo erectus → Homo sapiens → Ramapithecus → Homo habilis.

Write the key features of organic farming.

Give the diagnostic characters features of a Biome

Point out the biosphere reserves in Tamil Nadu.

Why does the zygote divides only after the division of Primary endosperm cell.

In Drosophila melanogaster, there are four pairs of chromosomes. If there occurs chromosomal aberrations resulting in trisomic and monnsomlc condition, what will be the chromosomal count? Write the correct chromosomal count against respective chromosomal aberration.

What is thermal stratification? Explain its types.

How do forests help in maintaining the climate?

Give an account on clonal selection.

1. Describe the structure of human ovary.

2. Write the preventive measures of STDs.

1. Explain the transcription process in prokaryotes with needed diagram.

2. Distinguish tenuinucellate and crassinucellate ovules.

1. Explain Dihybrid cross in pea plant.

2. Write the protocol for artificial seed preparation.

1. Point out any five morphological adaptations of epiphytes.

2. Generally in summer the forest are affected by natural fire. Over a period of time it recovers itself by the process of successions .Find out the types of succession and explain.

1. What are the effects of deforestation and benefits of agroforesty?

2. Give a detailed account on anyone fibe yielding plant.