CLASS XI

BIOLOGY (044)

SAMPLE PAPER-05

 

Max. Marks 70                                                                                                                                    Time allowed: 3 hours

General Instructions:

1) There are a total of 26 questions and five sections in the question paper. All the questions are compulsory.

2) Section A contains question number 1 to 5, Very Short Answer type questions of one mark each.

3) Section B contains question number 6 to 10, Short Answer type I questions of two marks each.

4) Section C contains question number 11 to 22, Short Answer type II questions of three marks each.

5) Section D contains question number 23, Value Based question of four marks each.

6) Section E contains question number 24 to 26, Long Answer type questions of five marks each.

7) There is no overall choice, however, internal choices have been provided in one question of two marks, one question of three marks and all three questions of five marks. An examinee has to attempt any one of the questions out of the two given in the question paper with the same question number.

SECTION - A

Question 1:  

In which group of plant kingdom would you place a plant bearing naked seeds and having its reproductive structures compactly arranged into cones?

Question 2:

Which level of protein folding is exhibited by the adult human haemoglobin?

Question 3:

Name the primary CO₂ acceptor in C₃ and C₄ pathways of carbon dioxide fixation.

Question 4:

In which organ does ammonia gets converted into urea?

Question 5:

Mention the hormonal basis of diabetes mellitus and diabetes insipidus.

Section - B

Question 6:  

What is the term given to the symbiotic association between algae and fungi? State its significance. Briefly explain the terms ‘mycobiont’ and ‘phycobiont’ related to this association.

Question 7:

Give the technical term for each of the following case:

1. When stamens are attached to the petals.

2. When all the stamens unite by their filaments to form a single bundle.

3. When there are more than one carpel, each of which is free.

4. Type of placentation in which the placenta forms a ridge along the ventral suture.

Question 8:

State the contribution of the following scientists:

1. Rudolf Virchow

2. Singer and Nicolson

3. George Palade

4. Robert Brown

OR

What is a mesosome? In which type of cell is it seen? Mention the functions it performs.

Question 9:

Explain how auxins are concerned with the bending of shoot towards the light source.

Question 10:

Define the following terms:

i. Cardiac output

ii. Cardiac cycle

SECTION - C

Question 11:

What is meant by ‘heterospory’? State its significance. Give a few example of pteridophytes that exhibit heterospory.

Question 12:

List down at least three characteristics of Class Aves and Class Mammalia.

Question 13:

Draw a well labeled cellular diagram of a transverse section through the dicotyledonous stem.

OR

Draw a well labeled diagram of the digestive system of a frog.

Question 14:

Give a brief account of the internal structure of the mitochondria with the help of a diagram.

Question 15:

What are co-factors? Discuss briefly the various types of co-factors.

Question 16:

Differentiate between the following pairs:

i. Cyclic and non – cyclic photophosphorylation.

ii. C₃ and C₄  pathways of CO₂ fixation.

Question 17:

With the help of a flowchart, show the various steps of EMP pathway.

Question 18:

Explain why:

(i) Gibberellin is used to induce reversal of dwarfism in genetically dwarf plants.

(ii) Auxins are called root-initiating hormones.

(iii) A farmer uses cytokinins to increase the number of female flowers in cucumber plants growing in his field.

Question 19:

What is Blackman’s law of limiting factors? Briefly explain how does concentration of carbon dioxide controls the rate of photosynthesis.

Question 20:

Give a comparison between the three types of blood vessels found in human beings.

Question 21:

Explain the following pulmonary volumes and capacities:

i. Inspiratory Reserve Volume (IRV)

ii. Vital Capacity (VC)

iii. Residual Volume (RV)

Question 22:

How can you account for the following?

i. During daytime, we fail to see for a moment on entering a dark room.

ii. No image is formed at the exit of optic nerve though it is the part of the photosensitive layer.

SECTION - D

Question 23:

In a biology practical class, the teacher focused a cell under the high power of a compound microscope. He then asked his students to identify the cell whether it is prokaryotic or eukaryotic. Some students identified it as a prokaryotic cell while some identified it as an eukaryotic cell. The teacher finally informed the students that it was a prokaryotic cell.

i. Discuss the basis of the teacher’s conclusion.

ii. Suggest four features in which a prokaryotic cell differs from a eukaryotic cell?

iii. Name the kingdom which solely consists of prokaryotes. What is the material with which a prokaryotic cell well is generally made up of?

SECTION - E

Question 24:

Give reasons for the following:

1. All vertebrates are chordates but all chordates are not vertebrates.

2. Frogs and lizards are generally not seen during winters.

3. A cartilaginous fish swims continuously to remain at a particular depth in water.

4. Mosses are amphibious in nature.

5. Members of Deuteromycetes are called ‘fungi imperfecti’.

OR

What is meant by placentation? Briefly describe its various types of placentation with the help of diagrams. Also mention one example of each.

Question 25:

Study the figure given above and answer the questions that follow:

(i) Why does the velocity of the reaction not increase after reaching V_max with further increase in the concentration of the substrate?

(ii) What is meant by inhibition? What is a ‘competitive inhibitor’?

(iii) How does a ‘competitive inhibitor’ inhibits the activity of the enzyme?

(iv) Give an example of competitive inhibition.

OR

(i) Why is respiration known as the ‘amphibolic pathway’? Explain with the help of a schematic representation.

(ii) What is respiratory quotient? How can it be used to determine the respiratory substrate used during respiration?

Question 26:

Explain how does a sarcomere aids in providing contractility to the muscles according to the sliding filament theory.

OR

(i) Explain the process of urine formation in humans.

(ii) List down any four abnormalities seen in the constitution of the urine.

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