MID TERM EXAMINATION
XII SCIENCE BIOLOGY (56) Max. Marks: 50
DATE: /--/20-- (5 Pages) Time : 2 Hrs
General Instructions:
The question paper is divided into four sections.
(1) Section A: Q. No. 1 contains Seven multiple choice type questions carrying
one mark each.
(i) For each multiple choice type of question, it is mandatory to write the correct answer along with its alphabet. e.g.,
(a) .......... / (b) .............. / (c) ................ / (d) ........... etc.
No marks shall be given if ONLY the correct answer or alphabet of the correct answer is written.
(ii) In case of MCQ evaluation will be done for the first attempt only.
Q. No. 2 Contains Seven very short answer type of questions carrying one mark each.
(2) Section B: Q. No. 3 to 13 are short answer type of questions carrying two marks each ( Attempt any Eight)
(3) Section C: Q. No. 14 to 19 are short answer type questions carrying three marks each. ( Attempt any Four)
(4) Section D: Q. No. 20 to 23 are long answer type questions carrying four marks each. (Attempt any Two)
(5) Begin the answer of each section on a new page.
SECTION – A
Q. 1. Select and write the correct answer for the following multiple-choice type of
questions: [07]
(i) Genetically dissimilar offsprings can be produced by ..................
a] Asexual reproduction b] Sexual reproduction
c] Vegetative propagation d] Tissue culture
(ii) In adventive polyembryony, an embryo develops directly from
the diploid cell of nucellus and integuments as in .............
a] Catharanthus b] Vallisneria
c] Citrus d] Zostera
(iii) The connection of ...................... with hypophysis gland is lost in embryo.
a] Infundibulum b] Sella turcica
c] Hypothalamus d] Rathke’s pouch
(iv) The two or more alternative forms of a gene are called .......... of each
other.
a] co-factors b] alleles
c] companions d] homologues
(v) When a single gene controls two or more different traits, then
the phenomenon is called ...................
a] co-dominance b] multiple alleles
c] pleiotropism d] polygenic inheritance
(vi) The two hemispheres internally connected to each other by a
thick band of nerve fibres called .............
a] corpus callosum b] crura cerebri
c] corpora quadrigemina d] pons varolii
(vii) It translates the thoughts into speech.
a] Broca’s area b] Association area
c] Olfactory area d] Auditory area
Q. 2. Answer the following questions: [07]
(i) Define: Parthenocarpy
(ii) Name the plant showing protogyny.
(iii) Name the hormones showing following functions –
a) It stimulates contraction of uterus during parturition.
b) It increases blood pressure by causing vasoconstriction.
(iv) What is pure line?
(v) State ‘Law of Dominance’.
(vi) Give function of mechanoreceptors.
(vii) Identify the receptor, which is sensitive to stimuli like hunger, thirst, etc.
SECTION – B
Attempt any EIGHT of the following questions: [16]
Q. 3. Give floral adaptations for pollination shown by bottle brush.
Q. 4. What is geitonogamy? How it differs from xenogamy?
Q. 5. (a) Draw a neat diagram of male gametophyte.
(b) Label male gamete and tube nucleus.
(c) Give function of pollen tube.
Q. 6. Why law of segregation is also called the law of purity of gametes?
Q. 7. Enlist the generalizations based on Mendel’s experiments.
Q. 8. Match the column -I with column –II and rewrite the matching pairs.
Column - I | Column - II |
A. Hyposecretion of STH in childhood | 1. Diabetes insipidus |
B. Hypersecretion of GH in childhood | 2. Acromegaly |
C. Hypersecretion of GH in middle aged adults | 3. Pituitary dwarfism |
D. Deficiency of ADH | 4. Gigantism |
Q. 9. a) Name the part of the hypophysis which is poorly developed in human beings.
b) Give function of Melanocyte Stimulating Hormone.
Q. 10. (a) What are spinal nerves?
(b) Enlist the branches of spinal nerve.
Q. 11. (a) Name the organ located in the orbit of skull.
(b) What is uvea?
(c) Enlist the photoreceptor cells located in macula lutea.
Q. 12. (a) Sketch neat diagram of brain to show ventricles in sagittal plane.
(b) Label interventricular foramen and cerebral aqueduct.
Q. 13. Complete the following chart and rewrite.
Group | No. of pairs | Region of origin from vertebral column |
Cervical | 8 | -------------- |
Thoracic | -------------- | Thorax |
Lumbar | 5 | -------------- |
-------------- | 5 | Pelvis |
Coccygeal | 1 | Coccyx |
SECTION – C
Attempt any FOUR of the following questions: [12]
Q. 14. Enlist the events happened during double fertilization.
Q. 15. a) Define Apomixis.
b) Match the column -I with column –II and rewrite the matching pairs.
Column - I | Column - II |
A. Diplospory | 1. Orange |
B. Apospory | 2. Lemon |
C. Apogamy | 3. Taraxacum |
D. Adventive embryony | 4. Nicotiana |
Q. 16. The basic principle of genetics was developed by Mendel. State and explain
it with suitable example.
Q. 17. a) Name the gland which is sensitive to the biochemical signals of light.
b) Enlist the functions of melatonin.
Q. 18. Describe protective membranes of central nervous system.
Q. 19. With the help of a suitable example, write the mechanism of hormone action through membrane receptors.
SECTION – D
Attempt any TWO of the following. [08]
Q. 20. (a) Kabban Park in Bengaluru is having dull flowers with strong fragrance, abundant nectar and edible pollen grains. Identify the type of pollination, the flowers are adapted for.
(b) The process of fruit formation without fertilization is termed as __________.
(c) Differentiate between albuminous and exalbuminous seeds.
Q. 21. Give the graphic representation of back cross and test cross.
Differentiate between them.
Q. 22. (a) Name the nerve fibres internally connecting the cerebral hemispheres.
(b) Name the sulci which divide each cerebral hemisphere into 4 lobes.
(c) Describe the various functional areas found in the different lobes of cerebral hemispheres.
Q. 23. Answer the questions after observing the diagram given below.
(a) What do the synaptic vesicle contain?
(b) What process is used to release the neurotransmitter?
(c) What should be the reason for the next impulse to be conducted?
