Tamil Nadu 11th Biology Model Question Paper 4 English Medium

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TN State Board 11th Biology Model Question Paper 4 English Medium

Instructions:

  1. The question paper comprises of four parts Questions for Botany and Zoology are asked separately.
  2. You are to attempt all the parts. An internal choice of questions is provided wherever applicable.
  3. All questions of Part I, II, III, and IV are to be attempted separately.
  4. Question numbers 1 to 8 in Part I are Multiple Choice Questions of one mark each. These are to be answered by choosing the most suitable answer from the given four alternatives and Writing the option code and the Corresponding answer.
  5. Question numbers 9 to  4 in Part II are two-marks questions. This also is answered in about one or list sentences.
  6. Question numbers 15 to 19 in Part III are three-marks questions These are to be answered in about three to five short sentences.
  7. Question numbers 20 and 21 in Part  IV are five-marks questions. These are to be answered in detail Draw diagrams wherever necessary.

Time: 3 Hours
Maximum Marks: 70

Bio-Botany [Maximum Marks: 35]

Part – I

Answer all the questions. Choose the correct answer.  [8 × 1 = 8]

Question 1.
Six kingdom classification was proposed by ………………………
(a) Haeckel
(b) Copeland
(c) Woese
(d) Cavalier-Smith
Answer:
(d) Cavalier-Smith

Tamil Nadu 11th Biology Model Question Paper 4 English Medium

Question 2.
Clasping roots are also called as ………….
(a) pillar
(b) stilt
(c) clinging
(d) buttress
Answer:
(c) clinging

Question 3.
The coconut water and the edible part of coconut are equivalent to ………………………
(a) endosperm
(b) endocarp
(c) mesocarp
(d) embryo
Answer:
(a) endosperm

Question 4.
The first botanical garden was established and maintained by………………………
(a) Linnaeus
(b) Babylonians
(c) Theophrastus
(d) Stebbins
Answer:
(c) Theophrastus

Tamil Nadu 11th Biology Model Question Paper 4 English Medium

Question 5.
The DNA protein complex present in the centromere is………………………
(a) Cyclin
(b) Kinesis
(c) MPF
(d) Kinetochore
Answer:
(d) Kinetochore

Question 6.
In cucurbitaceae, the vascular bundles are………………………
(a) Bicollateral
(b) Collateral closed
(c) Concentric
(d) Radial
Answer:
(a) Bicollateral

Question 7.
Which of the following performs anaerobic photosynthesis?
(a) Green sulphur bacteria
(b) Cyanobacteria
(c) Purple sulphur bacteria
(d) Green filamentous bacteria
Answer:
(b) Cyanobacteria

Tamil Nadu 11th Biology Model Question Paper 4 English Medium

Question 8.
Identify the day neutral plants.
(a) Pea
(b) Wheat
(c) Tomato
(d) Soyabean
Answer:
(c) Tomato

Part – II

Answer any four of the following questions. [4 × 2 = 8]

Question 9.
What are Archaebacteria?
Answer:
Archaebacteria are primitive prokaryotes and are adapted to thrive in extreme environments like hot springs, high salinity and low pH. e.g., Thermoplasma.

Question 10.
What is root cap? Mention its role.
Answer:
Root tip is covered by a dome shaped parenchymatous cells called root cap. It protects the meristematic cells in the apex.

Question 11.
What do you understand by the term “Pomology”?
Answer:
The branch of horticulture that deals with the study of fruits and their cultivation is called pomology.
Classify plastids based on storage & mention their storage component.

Tamil Nadu 11th Biology Model Question Paper 4 English Medium

Question 12.
Classify plastids based on storage & mention their storage component.
Answer:

S.No. Plastids Storage Content
1. Amyloplast Starch
2. Elaiplast Lipids/Oils
3. Aleuroplast or Proteoplast Protein

Question 13.
Which meristem is responsible for secondary growth in dicots? Mention its types.
Answer:
Secondary growth in dicots is the responsibility of lateral meristems. They are vascular cambium and cork cambium.

Question 14.
Give an account of Xanthophylls.
Answer:
Yellow (C40H56O2) pigments are like carotenes but contain oxygen. Lutein is responsible for yellow colour change of leaves during autumn season. Examples: Lutein, Violaxanthin and Fucoxanthin.

Part – III

Answer any three questions in which question number 19 is compulsory. [3 x 3 = 9]

Question 15.
Point out the demerits of five kingdom classification.
Answer:

  • The kingdom Monera and Protista accommodate both autotrophic and heterotrophic organisms, cell wall lacking and cell wall bearing organisms thus making these two groups more heterogeneous.
  • Viruses were not included in the system.

Question 16.
How the leaf hooks helps the Bignonia plant?
Answer:
In cat’s nail (Bignonia unguiscati) an elegant climber, the terminal leaflets become modified into three, very sharp, stiff and curved hooks, very much like the nails of a cat. These hooks cling to the bark of a tree and act as organs of support for climbing.

Tamil Nadu 11th Biology Model Question Paper 4 English Medium

Question 17.
List out the properties of Water.
Properties of Water :

  • Adhesion and cohesion property
  • High latent heat of vaporisation
  • High melting and boiling point
  • Universal solvent
  • Specific heat capacity

Question 18.
Draw the stoma with dumb-bell shaped guard cell.
Answer:
Tamil Nadu 11th Biology Model Question Paper 4 English Medium - 1

Tamil Nadu 11th Biology Model Question Paper 4 English Medium

Question 19.
Define the term “Translocation of organic solutes”.
Answer:
The phenomenon of food transportation from the site of synthesis to the site of utilization is known as translocation of organic solutes. The term solute denotes food material that moves in a solution.

Part – IV

Answer all the questions. [2 × 5 = 10]

Question 20.
Describe the salient features of Phaeophyceae members.
Answer:

  1. Phaeophyceae commonly called as Brown algae.
  2. Majority are marine habitats. Pleurocladia is a fresh water form.
  3. Thallus may be filamentous, frond-like or giant kelps.
  4. Thallus is differentiated into photosynthetic part-frond, stalk-like structure-stipe and a holdfast for attachment.
  5. Chlorophyll ‘a’ and ‘c’, carotenoids and Xanthophylls are photosynthetic pigments.
  6. A golden brown fucoxanthin pigment gives olive green to brown colour.
  7. Mannitol and Laminarin starch is the storage material.
  8. Motile spores with unequal flagella (one whiplash and one tinsel) are present.
  9. Oogamous is the major type of sexual reproduction. Isogamy is also seen.
  10.  Alternation of generation is seen. Example: Sargassum, Fucus, Laminaria and Dictyota.

[OR]

Compare Transmission Electron Microscope with Scanning Electron Microscope.
Answer:
Tamil Nadu 11th Biology Model Question Paper 4 English Medium - 2

Tamil Nadu 11th Biology Model Question Paper 4 English Medium

Question 21.
Compare photosynthesis in plants & bacteria.
Answer:
Photosynthesis in Plants :

  1. Cyclic and non-cyclic phosphorylation takes place.
  2. Photosystem I and II involved.
  3. Electron donor is water.
  4. Oxygen is evolved.
  5. Reaction centres are P700 and P680.
  6. Reducing agent is NADPH + H+.
  7. PAR is 400 to 700 nm.
  8. Chlorophyll, carotenoid and xanthophyll.
  9. Photosynthetic apparatus – chloroplast.

Photosynthesis in Bacteria :

  1. Only cyclic phosphorylation takes place.
  2. Photosystem I only involved.
  3. Electron donor is H2S.
  4. Oxygen is not evolved.
  5. Reaction centre is P870.
  6. Reducing agent is NADPH + H+.
  7. PAR is above 700 nm.
  8. Bacterio chlorophyll and bacterio viridin.
  9. It is chlorosomes and chromatophores.

[OR]

Explain the physiological effect of Ethylene.
Answer:

  • Ethylene stimulates respiration and ripening in fruits.
  • It stimulates radial growth in stem and root and inhibits linear growth.
  • It breaks the dormancy of buds, seeds and storage organs.
  • It stimulates formation of abscission zone in leaves, flowers and fruits. This makes the leaves to shed prematurely.
  • Inhibition of stem elongation (shortening the intemode).
  • In low concentration, ethylene helps in root initiation.
  • Growth of lateral roots and root hairs. This increases the absorption surface of the plant roots.
  • The growth of fruits is stimulated by ethylene in some plants. It is more marked in climacteric fruits.
  • Ethylene causes epinasty.

Bio-Zoology

Part – I

Answer all the questions. Choose the correct answer.  [8 × 1 = 8]

Question 1.
Uricotelisum is found in ……….
(a) Mammals and birds
(b) Birds, reptiles and insects
(c) Fishes and fresh water protozons
(d) Frogs and toads
Answer:
(b) Birds, reptiles and insects

Question 2.
Bone cells are called as …………..
(a) Neurons
(b) Osteoblasts
(c) Epithelial cells
(d) Chondrocytes
Answer:
(b) Osteoblasts

Tamil Nadu 11th Biology Model Question Paper 4 English Medium

Question 3.
SA-node stands for ………………
(a) Sinoatrial node
(b) Systolic atrial node
(c) Systemic atrial node
(d) Sino aorta node
Answer:
(a) Sinoatrial node

Question 4.
Match the List I and List II:
Tamil Nadu 11th Biology Model Question Paper 4 English Medium - 3
(a) 1 – (i), 2 – (ii), 3 – (iii), 4 – (iv)
(b) 1 – (ii), 2 – (i), 3 – (iv), 4 – (iii)
(c) 1 – (iv), 2 – (iii), 3 – (ii), 4 – (i)
(c) 1 – (iv), 2 – (iii), 3 – (ii), 4 – (iii)
Answer:
(b) 1 – (ii), 2 – (i), 3 – (iv), 4 – (iii)

Question 5.
Which of the following statement is correct?
(a) Polyp forms are free living
(b) Medusa forms are sessile
(c) Medusa produces gametes
(d) Polyp reproduces sexually
Answer:
(c) Medusa produces gametes

Tamil Nadu 11th Biology Model Question Paper 4 English Medium

Question 6.
Which of the following statement is in incorrect with regard to ecosystem?
(a) It includes living and non-living things
(b) It shows interrelationship among living things
(c) It shows interrelationship among living and non-living things
(d) It has a large number of species
Answer:
(b) It shows interrelationship among living things

Question 7.
What is Nissl’s granule consist of ?
(a) DNA
(b) RNA
(c ) Protein
(d) Lipid
Answer:
(c ) Protein

Question 8.
Ranikhet, coccidiosis and Fowl pox are ………………..
(a) Chicken breeds
(b) Types of poultry forming
(c) Poultry diseases
(d) Types of breeding methods
Answer:
(c) Poultry diseases

Part – II

Answer any four of the following questions. [4 × 2 = 8]

Question 9.
What are diploblastic animals?
Answer:
The animals in which the cells are arranged in two embryonic layers, the ectoderm and endoderm are called diploblastic animals.

Question 10.
Define Hermaphrodite.
Answer:
Hermaphrodite are animals with both male and female reproductive organs.

Question 11.
Difference between skeletal muscle and cardiac muscle.
Answer:
Skeletal muscle:

  1. Skeletal muscle are voluntary muscles
  2. Skeletal muscle are attached to the skeleton

Cardiac muscle :

  1. Cardiac muscle are involuntary muscles
  2. Cardiac muscles are attached to the heart.

Question 12.
How do we calculate BMI?
Answer:
Degree of obesity is assessed by body mass index (BMI). A normal BMI range for adult is 19-25; above 25 is considered as obese. BMI is calculated as body weight in Kg, divided by the square of body height in meters. For example, a 50 Kg person with a height of 160 cms would have a BMI of 19.5.
That is BMI = 50/1.62 = 19.5

Tamil Nadu 11th Biology Model Question Paper 4 English Medium

Question 13.
Draw the diagram of Rana hexadactyla.
Answer:
Tamil Nadu 11th Biology Model Question Paper 4 English Medium - 4

Question 14.
What are the functions of frontal lobe?
Answer:
The frontal lobe governs the Behaviour, Intelligence, Memory and Movement.

Part – III

Answer any three questions in which question number 19 is compulsory. [3 × 3 = 9]

Question 15.
Define five kingdom classification of Whittaker.
Answer:
R.H. Whittaker (1969) proposed the five kingdom classification. They included Monera, Protista, Fungi, Plantae and Animalia. He classified organisms based on cell structure, nutrition, reproduction and phylogenetic relationships.

Question 16.
Distinguish between Oviparous and Viviparous animals.
Question
Oviparous animals

  1. The egg laying animals are known as Oviparous animals.
  2. They make contain yolk for embryonic development, eg.

Viviparous animals

  1. The animals which give birth to young ones are called Viviparous animals.
  2. Birds The developing embryo derives nutrients from the parent, eg. Man

Tamil Nadu 11th Biology Model Question Paper 4 English Medium

Question 17.
Label the given diagram.
Answer:
Tamil Nadu 11th Biology Model Question Paper 4 English Medium - 5

Question 18.
Define Isinglass.
Answer:
Isinglass is a high-grade collagen produced from dried air bladder or swim bladder of certain fishes. Viz. Catfish and carps. The processed bladder which is dissolved in hot water forms a gelatin having adhesive property. It is primarily used for classification of wine, beer and vinegar.

Question 19.
Write the symptoms of cretinism.
Answer:
Cretinism is caused due to hypothyrodisim in infants. A cretin child shows the following symptoms:

  1. Retarded skeletal growth
  2. Absence of sexual maturity
  3. Retarded mental ability
  4. Thick and short limbs
  5. Bloated face

Part – IV

Answer all the questions. [2 × 5 = 10]

Question 20.
Explain the classification of animal tissues.
Answer:
Tamil Nadu 11th Biology Model Question Paper 4 English Medium - 6

Tamil Nadu 11th Biology Model Question Paper 4 English Medium

[OR]

What are the disorders of the respiratory system?
Answer:
Respiratory system is highly affected by environmental, occupational, personal and social factors. These factors may be responsible for a number of respiratory disorders. Some of the disorders are discussed here.

Asthma-It is characterized by narrowing and inflammation of bronchi and bronchioles and difficulty in breathing.Common allergens for asthma are dust, drugs, pollen grains, certain food items like fish, prawn and certain fruits etc.

Emphysema- Emphysema is chronic breathlessness caused by gradual breakdown of the thin walls of the alveoli decreasing the total surface area of a gaseous exchange, i.e., widening of the alveoli is called emphysema. The major cause for this disease is cigarette smoking, which reduces the respiratory surface of the alveolar walls.

Bronchitis-The branch? when it gets inflated due to pollution smoke and cigarette smoking, causes bronchitis. The symptoms are cough, shortness of breath and sputum in the lungs.

Pneumonia-Inflammation of the lungs due to infection caused by bacteria or vims is called pneumonia. The common symptoms are sputum production, nasal congestion, shortness of breath, sore throat, etc.

Tuberculosis-Tuberculosis is caused by Mycobacterium tuberculae. This infection mainly occurs in the lungs and bones.Collection of fluid between the lungs and the chest wall is the main complication of this disease.

Occupational respiratory disorders-The disorders due to one’s occupation of working in industries like grinding or stone breaking, construction sites, cotton industries, etc. Dust produced affects the respiratory tracts.

Long exposure can give rise to inflammation leading to fibrosis. Silicosis and asbestosis are „ occupational respiratory diseases resulting from inhalation of particle of silica from sand grinding ‘ and asbestos into the respiratory tract. Workers, working in such industries must wear protective masks.

Tamil Nadu 11th Biology Model Question Paper 4 English Medium

Question 21.
Explain the mechanism of muscle contraction.
Answer:
Mechanism of muscle contraction:
Sliding filament theory in 1954, Andrew F.Huxley and Rolf Niedergerke proposed the sliding- filament theory to explain muscle contraction. According to this theory, overlapping actin and myosin filaments of fixed length slide past one another in an energy requiring process, resulting in muscle contraction. The contraction of muscle fibre is a remarkable process that helps in creating a force to move or to resist a load.

The force which is created by the contracting muscle is called muscle tension. The load is a weight or force that opposes contraction of a muscle. Contraction is the creation of tension in the muscle which is an active process and relaxation is the release of tension created by contraction. Muscle contraction is initiated by a nerve impulse sents by the central nervous system (CNS) through a motor neuron.

The junction between the motor neuron and the sarcolemma of the muscle fibre is called the neuromuscular junction or motor end plate. When nerve impulse reaches a neuromuscular junction, acetylcholine is released. It initiates the opening of multiple gated channels in sarcolemma. The action potential travels along the T-tubules and triggers the release of calcium ions from the sarcoplasmic reticulum.

The released calcium ions bind to troponin on thin filaments. The tropomyosin uncovers the myosinbinding sites on thin filaments. Now the active sites are exposed to the heads of myosin to form a cross-bridge. During cross-bridge formation actin and myosin form a protein complex called actomyosin.

Utilizing the energy released from hydrolysis of ATP, the myosin head rotates until it forms a 90° angle with the long axis of the filament. In this position myosin binds to an actin and activates a contraction – relaxation cycle which is followed by a power stroke.

The power stroke (cross-bridge tilting) begins after the myosin head and hinge region tilt from a 90° angle to a 45° angle. The cross-bridge transforms into strong, high-force bond which allows the myosin head to swivel. When the myosin head swivels it pulls the attached actin filament towards the centre of the A-band.
The myosin returns back to its relaxed state and releases ADP and phosphate ion. A new ATP molecule then binds to the head of the myosin and the cross-bridge is broken.

At the end of each power stroke, each myosin head detaches from actin, then swivels back and binds to a new actin molecule to start another contraction cycle. This movement is similar to the motion of an oar on a boat. At the end of each power stroke, each myosin head detaches from actin, then swivels back and binds to a new actin molecule to start another contraction cycle. The power stroke repeats many times until a muscle fibre contracts. The myosin heads bind, push and release actin molecules over and over as the thin filaments move toward the centre of the sarcomere.

The repeatedly formation of cross-bridge cycles cause the sliding of the filaments only but there is no change in the lengths of either the thick or thin filaments. The Z- discs attached to the actin filaments are also pulled inwards from both the sides, causing the shortening of the sarcomere (i.e. contraction). This process continues as long as the muscle receives the stimuli and a steady flow of calcium ions.

When motor impulse stops, the calcium ions are pumped back into the sarcoplasmic reticulum, results in the masking of the active sites of the actin filaments. The myosin head fails to bind with the active sites of actin and these changes cause the return of Z – discs back to their original position, i.e. relaxation.

Tamil Nadu 11th Biology Model Question Paper 4 English Medium

[OR]

Describe the central nervous system.
Answer:
Central neural system (CNS): The CNS includes the brain and the spinal cord, which are protected by the bones of the skull and vertebral column. During its embtyonic development, CNS develops from the ectoderm.

Brain: The brain acts as the command and control system. It is the site of information processing. It is located in the cranial cavity and is covered by three cranial meninges. The outer thick layer is Duramater which line? the inner surface of the cranial cavity; the median thin layer is Arachnoid mater which is separated from the duramater by a narrow subdural space.

The innermost layer is Piamater which is closely adhered to the brain but separated from the arachnoid mater by the subarachnoid space. The brain is divided into three major regions: Forebrain, Midbrain and Hindbrain.

Fore Brain: It comprises the following regions: Cerebrum and Diencephalon. Cerebrum is the ‘seat of intelligence and forms the major part of the brain. The cerebrum consists of an outer cortex, inner medulla and basal nuclei. The superficial region of the cerebrum is called cerebral cortex, which looks grey due to the presence of unmyelinated nerve cells. Cerebral cortex consists of neuronal cell body, dendrites, associated glial and blood vessels. The surface of the cerebrum shows many convolutions (folds) and grooves.

The folds are called gyri (singular gyrus); the shallow grooves between the gyri are called sulci (singular sulcus) and deep grooves are called fissures. These sulci and gyri increase the surface area of the cerebral cortex. Several sulci divide the cerebrum into eight lobes: a pair of frontals, parietals, temporals and occipital lobes.

Mid brain: The mid brain is located between the diencephalon and the pons. The lower portion of the midbrain consists of a pair of longitudinal bands of nervous tissue called cerebral peduncles which relay impulses back and forth between cerebrum, cerebellum, pons and medulla. The dorsal portion of the midbrain consists of four rounded bodies called corpora quadrigemina which acts as a reflex centre for vision and hearing.

Hind brain: Rhombencephalon forms the hind brain. It comprises of cerebellum, pons varolii and medulla oblongata. Cerebellum is the second largest part of the brain. It consists of two cerebellar hemispheres and central worm shaped part, the vermis. The cerebellum controls and coordinates muscular movements and body equilibrium. Any damage to cerebellum often results in uncoordinated voluntary muscle movements.

Pons varoli: It lies infront of the cerebellum between the midbrain and the medulla oblongata. The nerve fibres in the pons varolii form a bridge between the two cerebellar hemispheres and connect the medulla oblongata with the other region of the brain. The respiratory nuclei found in the pons cooperate with the medulla to control respiration.
Medulla oblongata: It forms the posterior most part of the brain. It connects the spinal cord with various parts of the brain. It receives and integrates signals from spinal cord and sends it to the cerebellum and thalamuj. Medulla contains vital centres that control cardio vascular reflexes, respiration and gastric secretions.