MODEL PAPER 2 BIOLOGY - MODEL PAPER 2

The oxygen - haemoglobin dissociation curve will show a right shift in case of:

Which of the following pairs is wrong?

A Prothallus is:

In the wheat field, some broad-leaved weeds were seen by a farmer, which plant hormone would you sugges getting rid of the same?

Frog shows which kind of excretion?

State the law proposed by Blackman for various factors operative for photosynthesis.

Write the equation to express Cornelius van Niel's findings.

Why there is a need to standardise the system of naming of living organisms?

What is the role of second messenger in protein hormone action?

How do different senses work in frog? Explain in brief.

Briefly describe the structure of the Brain.

Why is there no mixing of deoxygenated and oxygenated blood in the human heart normally?

Write the differences between:
a. Blood and Lymph
b. Open and Closed system of circulation
c. Systole and Diastole
d. P-wave and T-wave

What makes the synovial joint freely movable? List any two types of synovial joints.

State any three functions of indole acetic acid in plants.

The fungi constitute a unique kingdom of heterotrophic organisms. They show a great diversity in morphology
and habitat. Fungi are cosmopolitan and occur in air, water, soil, and on animals and plants. They prefer to grow in warm and humid places. Most fungi are heterotrophic and absorb soluble organic matter from dead substrates and hence are called saprophytes. When a fungus reproduces sexually, two haploid hyphae of compatible mating types come together and fuse. In some fungi, the fusion of two haploid cells immediately results in diploid cells (2n). The fungiform fruiting bodies in which reduction division occurs, leading to the formation of haploid spores. Symbionts - in association with algae as lichens and with roots of higher plants as mycorrhiza. Three types of reproduction occur in fungi



i. Observe the given flow chart of reproduction and mention which steps involves in the sexual cycle of fungi.
(1)
ii. What is Rhizopus? Also, mention Rhizopus - wheat rush a correct match? (1)
iii. What is Mycorrhiza? And mention its function. (2)

OR

In which form Fungi Stores Food Material? Do fungi have food vacuoles? (2)

Discuss the basic structural organisation of a typical cell.

Give a detail description of plastids with the help of suitable diagram.

Does pyruvic acid enter the Krebs' cycle directly?

Differentiate between Aerobic respiration and Fermentation.

Explain, why a pair of homologous chromosomes is genetically different, but a pair of sister chromatids is genetically identical before crossing over in meiosis.

Assertion (A): Elemental analysis gives the elemental composition of living tissues in the form of hydrogen
Reason (R): Wet weight is the weight of living tissue and the remains of living tissue after drying gives dry weight.

Assertion (A): Inspiration is initiated by the contraction of the diaphragm which increases the volume of the thoracic chamber in the antero-posterior axis.
Reason (R): The contraction of external intercostal muscles lifts up the ribs and the sternum causing an incn in the volume of the thoracic chamber in the dorso-ventral axis.

Assertion (A): Bacteria do not always move with the help of flagella.
Reason (R): Rotary motion of flagellum is employed by flagellated bacteria for movement.