ASSISI CONVENT SCHOOL
HALF YEALY EXAMINATION (2021-22)
CLASS-XII SUB-BIOLOGY
(Candidates are allowed additional 15 minutes for only reading the paper.
They must NOT start writing during this time) M.M70
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This paper comprises of TWO PARTS – Part I and Part II. Answer all questions.
Part I contains twenty questions of one mark each.
Part II consists of Section A, B & C.
Section A contains seven questions of two marks each
Section B contains seven questions of three marks each, and Section C contains three questions of five marks
each.
Internal choices have been provided in two questions in Section A, two questions in Section B and in all
three questions of Section C.
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PART I (20 Marks)
Answer all questions.
Question 1
(a) Give one significant difference between each of the following: [5]
(i) Viviparous and Oviparous
(ii) Microsporangium and Megasporangium
(iii) Asexual Reproduction and Sexual Reproduction
(v) Vasectomy and Tubectomy.
(vi) Monohybrid Cross and Dihybrid Cross
(b) Explain the following terms: [5]
(i) Genome (ii) Spermiation (iii)Ovulation (iv)Allele (v)Emasculation
(c) Choose the correct answer from the following questions. [6]
(i) Haemophilia is a
(a) Y linked (b) Autosomal Sex Disorder (c) X linked Disorder (d) Deficiency disorder
(ii) Embryo sac is known as:
(a) Microgametophyte (b) Megagametophyte (c) Megasporangium (d) Microsporangium
(iii) GIFT mixes egg and sperm in the
(a) Fallopian tube (b) Uterus (c) Vagina (d) Culture medium
(iv) The vas deferens receives duct from the seminal vesicles and opens into urethra as:
(a)Epididymis (b) Prostate gland (c) Seminiferous tubules (d) Vas Deferens
(v) A cell formed from cleavage is called:
(a) Blastomere (b) Morula (c) Blastula (d) Gastrula
(vi) Crossing over most commonly occurs during:
(a) Telophase (b) Anaphase (c) Prophase (d) Prophase
(d) Give one significant contribution of each of the following scientists: [4×1]
(i) Walter Sutton and Theoder Boveri
(ii) Hugo De vries
(iii) T.H. Morgan
(iv) R C Punett
PART II
SECTION A (14 Marks)
(Answer all questions)
Question 2 [2]
(i) Draw a labelled diagram of human ovum.
OR
(ii) Draw a labelled diagram of human sperm.
Question 3 [2]
If phenotype of father is blood group ‘O’ and genotype of mother is heterozygous ‘A’ , what are the possible
genotypes and phenotypes of the offspring?
Question 4 .State four features of flowers pollinatedby insects [2]
Question 5 .Define life span. Give the life span of elephant. [2]
Question 6. [2]
Explain law of segregation
Question 7 [2]
What is IUDS Intra Utrine Contraceptive methods.
Question 8 [2]
(i) Give significant differences between Menarche and Menopause.
OR
(ii) Fertilization or Parturation.
SECTION B (21 Marks) (Answer all questions)
Question 9 [3]
(i) Explain the steps involved in artificial hybridization
OR
(ii) Write short note on Endosperm.
Question 10 [3]
Explain Incomplete Dominance with example.
Question 11
What is a test cross? How can it decipher the heterozygosity of a plant. [3]
Question 12 [3]
Draw schematic representation of binary fission in Amoeba.
Question 13 [3]
What are the three phases of in the life cycle of an organism ?
Question 14 [3]
Why is breastfeeding recommended during the initial period of infant’s growth?
Question 15 [3]
Draw a labelled diagram of the T.S of anther.
OR
Draw a labelled diagram of the LS of anatropous ovule.
SECTION C (15 Marks)
(Answer all questions)
Question 16 [5]
(i) Give the functions of placenta in human females.
OR
(ii) Explain male reproductive structure.
Question 17 [5]
(a) Expand the following terms and explain them briefly:
(i) GIFT
(ii) ZIFT
(iii) RCH
(vi) ICSI
(v) IVF
Question 18 7uyh6j[5]
(a) Answer the following questions:
(i) explain types of pollination with example.
(ii) A snapdragon plant with red flowers was crossed with a plant with white flowers. It produced pink
progeny in the F1 generation. Explain the principle of inheritance involved with the help of Punnett square.
OR
(b) Briefly describe the mechanism of development of dicot embryo
