MODEL PAPER 9 BIOLOGY - MODEL PAPER 9

Which of the following is included in bioinsecticide?

Source of energy in an ecosystem is:

XO type of sex determination is found in:

Growth curve is normally:

Name the spermicidal cream developed by Central Drug Research Institute (Lucknow), India.

Arrange the following in the decreasing order (most important first) of their importance, for the welfare of human society. Give reasons for your answer.
Biogas, Citric acid, Penicillin and curd

Name the microbes that help production of the following products commercially:
(a) Statin
(b) Citric acid
(c) Penicillin
(d) Butyric acid

These pictures show the gynoecium of (A) Papaver and (B) Michelia flowers, Write the difference in the structure of their ovaries.

Read the sequence of the nucleotides in the given segment of mRNA and the respective amino acid sequence in the polypeptide chain.

Polypeptide: met-phe-met-proline-valine-serine
i. Provide the triplet of bases (codon) for
a. valine
b. proline
ii. Write the nucleotide sequence of the DNA strand from which this mRNA was transcribed
iii. What does the last codon of this RNA stand for?

What are transgenic animals? How was the first transgenic cow found to be more useful than the normal cow, for humans?

Give three hypothesis for explaining why tropics show greatest levels of species richness.

Briefly classify the extinction processes.

Differentiate between vaccination and immunization. Describe the two types of vaccines with suitable examples?

Look at the figure below depicting lac operon of E.coli.

i. What could be the series of events when an inducer is present in the medium in which E.coli is growing?
ii. Name the inducer.

What data support that the evolutionary history of man is like that of any other organism?

Differentiate between:
a. hypocotyol and epicotyl
b. coleoptile and coleorrhiza
c. integument and testa
d. perisperm and pericarp

Study the figure of vector pBR322 given below in which foreign DNA is ligated at the Bam HI site of tetracyline resistance gene.

Answer the following questions:
i. Mention the function of rop.
ii. What will be the selectable marker for this recombinant plasmid and why?
iii. Explain transformation.

The melding of a technique for repeated rounds of DNA synthesis with the discovery of a thermostable DNA polymerase has given scientists the very powerful technique known as polymerase chain reaction (PCR). PCR is based on three simple steps required for any DNA synthesis reaction: (1) denaturation of the template into single strands; (2) annealing of primers to each original strand for new strand synthesis; and (3) extension of the new DNA strands from the primers.
In the given figure, one cycle of polymerase chain reaction (PCR) is shown:

i. Name the steps A, B and C.
ii. Give the purpose of each of these steps.
iii. State the contribution of Thermus aquaticus in this process.

Describe the structure of a ribosome, taking into consideration, its role in protein synthesis.

Give an account of the methods used in sequencing the human genome.

Assertion (A): Epiphytes grow on other plants.
Reason (R): They grow only in humid areas.

Assertion (A): The earliest organisms that appeared on the earth were non-green and presumably anaerobes.
Reason (R): The first autotrophic organisms were the chemo-autotrophs that never released oxygen.

Assertion (A): Ormeloxifene, also known as centchroman, is used as a nonsteroidal oral contraceptive.
Reason (R): It causes an asynchrony in the menstrual cycle between ovulation and the development of the uterine lining.

Assertion : The use of fertilizers greatly enhances crop productivity.
Reason : Irrigation is very important in increasing crop productivity.

Read the following text carefully and answer the questions that follow:
When a microorganism invades a host, a definite sequence of events usually occur leading to infection and disease, causing suffering to the host. This process is called pathogenesis. Once a microorganism overcomes the defense system of the host, development of the disease follows a certain sequence of events as shown in the graph. Study the graph given below for the sequence of events leading to appearance of a disease and answer the questions that follow:

i. In which period, according to the graph there are maximum chances of a person transmitting a disease/infection and why? (1)
ii. Study the graph and write what is an incubation period. Name a sexually transmitted disease that can be easily transmitted during this period. Name the specific type of lymphocytes that are attacked by the pathogen of this disease. (1)
iii. Draw a schematic labelled diagram of an antibody. (2)
OR
In which period, the number of immune cells forming antibodies will be the highest in a person suffering from pneumonia?
Name the immune cells that produce antibodies. (2)

Read the following text carefully and answer the questions that follow:

i. Identify the hormones X and Y respectively. (1)
ii. Label W and Z. (1)
iii. Name the hormones produced only during pregnancy in human female. Mention their source organs. (2)
OR
Name any two hormones which are secreted by placenta and are also present in a non-pregnant woman. (2)