Kerala Plus Two Zoology Question Paper March 2023 with Answers

Teachers recommend solving Kerala Syllabus Plus Two Zoology Previous Year Question Papers and Answers Pdf March 2023 to improve time management during exams.

Kerala Plus Two Zoology Question Paper March 2023 with Answers

I. Answer any 3 questions from 1-5. Each carries 1 score. (3 × 1 = 3)

Question 1.
Select the odd one. Justify your selection. (Rete testis, Vasa efferentia, Fallopian tube, Vas deferens)
Answer:
Fallopian tube.

Question 2.
Write the Central dogma in Molecular biology.
Answer:
Genetic information flows from DNA-» mRNA —» Protein

Question 3.
Which microbe is called baker’s yeast?
(A) Propionibacterium sharmanii
(B) Lacto bacillus
(C) Saccharomyces cerevisiae
(D) Aspergillus niger
Answer:
Saccharomyces cerevisiae

Question 4.
Pick out the correct pair of disease and its pathogen:
(A) Filaria – Rhino virus
(B) Typhoid – Streptococcus
(C) Malaria – Plasmodium
(D) Ascariasis – Entamoeba
Answer:
Malaria-Plasmodium.

Question 5.
Identify two ex-situ conservation approaches of or-ganisms from the following list:(Zoological Park, Biosphere Reserve, National Park, Botanical Garden)
Answer:
Zoological Park, Botanical Garden.

II. Answer any 9 questions from 6-16. Each carries 2 scores.

Question 6.
Placenta also act as an endocrine tissue and produce several hormones.
(A) Name any two placental hormones.
(B) Write two functions of Placenta, (other than endocrine function)
Answer:
(A) 1. Human chorionic gonadotropin
2. Human placental lactogen

(B) It facilitates the supply of oxygen and nutrients to the embryo.
• It helps to remove CO₂ and excretory wastes produced by the embryo.

Question 7.
The graph given below shows the ovarian events and ovarian hormone levels during menstrual cycle

(i) Name hormones A and B.
(ii) Write the ovarian events during luteal phase.
Answer:
(i) A-Progesterone
B – Estrogen.

(ii) The remaining parts of the Graafian follicle transform as the corpus luteum.
• It secretes large amounts of progesterone essential for maintenance of endometrium.

Question 8.
What are lUDs? Name one copper releasing and one hormone releasing lUDs.
Answer:
lUD’s (Intra Uterine Devices) :-These devices that are inserted by doctor or expert nurse into the uterus through vagina.

• Copper releasing lUDs .
Eg CuT, Cu7 & Multiload 375

• Hormone releasing lUDs.
Eg Progestasert, LNG -20 (Any one example in each)

Question 9.
Match the following:

Genetic Disorders	Genetic Reasons
Klinefelter’s syndrome	21st Trisomy
Down’s syndrome	Lack of one ‘X’ chromosome in females(XO)
Turner’s syndrome	Due to autosomal recessive trait
Phenylketonuria	Presence of an extra X chromosome in males (XXY)

Answer:

Genetic Disorders	Genetic Reasons
Klinefelter’s Syndrome	Presence of an extra X chromosome in males (XXY)
Down’s Syndrome	21st Trisomy.
Turner’s Syndrome	Lack of one ‘X’ chromosome in female (XO).
Phenylketonuria	Due to autosomal recessive trait.

(i) A-Terminator gene B – Coding strand
(ii) It determines the base sequence in mRNA

Question 10.
Schematic representation of a transcription unit is given;

(i) Fill up the missing parts A and B.
(ii) Write the role of template strand in transcription.
Answer:
(A) The organs that are having similar function but differ in structure and origins.
(B) Eyes of octopus and mammals, Wings of butterfly and birds

Question 11.
(A) Define Analogous organs.
(B) Identify analogous organs from the given ex-amples :
(i) Eyes of octopus and mammals
(ii) Vertebrate hearts
(iii) Wings of butterfly and bird
(iv) Forelimbs of Cheetah and Human
Answer:
(A) The organs that are having similar function but differ in structure and origins.
(B) Eyes of octopus and mammals, Wings of butterfly and birds

Question 12.
Using the given terms in brackets, complete the following evolutionary stages of man :
(Homo sapiens, Homo habilis, Homo erectus, Australopithecines)

A – Australopithecines
B – Homo habilis
C- Homo erectus
D – Homo sapiens

Question 13.
Differentiate between Active immunity and Passive immunity.
Answer:

• Active Immunity
  1. Antibodies are produced in the host body when pathogen is entered into body.
  2. It shows the property of memory.
• Passive Immunity
  1. Ready-made anti-bodies are directly injected into the body.
  2. Memory property is absent.

Question 14.

Write some important measures that would be use-ful for the prevention and control of alcohol and drug abuse among adolescents.(Write relevant four points)
Answer:

1. Avoid undue pressure in adolescence
2. Proper education and counselling
3. Providing help from parents
4. Peer group looking for the danger sign

Question 15.
Two bioactive molecules are given :
(i) Cyclosporin-A
(ii) Streptokinase
(A) Name the microbe,which produces these bioactive molecules.
(B) Write its use.
Answer:
(A) Trichoderma polysporum. Used as Immunosuppressive agent.
(B) Streptococcus. Used as clot buster (Removing the clot)

Question 16.
A figure showing the global biodiversity of inverte-brates and vertebrates are given.

(A) Identify the most diverse groups of vertebrates and invertebrates.
(B) What are the three important levels of biodiversity?
Answer:
(A) Vertebrates – Fishes Invertebrates – Insects
(B) Genetic Diversity, Species diversity, Ecological diversity

III. Answer any 3 questions from 17 to 20. Each

Question 17.
(A) What are STIs?
(B) Give two examples!
(C) Write any two preventive measures of STIs.
Answer:
(A) Sexually Transmitted Infections
(B) Gonorrhoea and Syphilis.
(C) Avoid sex with unknown partners. Always use condoms during coitus.

Question 18.
Cross between Red flower (RR) and white flower (rr) bearing plants of Snapdragon produced all plants with pink flowers in F₁ generation.
(A) Name the genetic phenomenon of this cross.
(B) Illustrate F2 generation of this cross using Punnet square.
Answer:
(A) Incomplete Dominance
(b)

Question 19.
The given illustration shows ‘Evil Quartet’ of biodiversity loss :

(i) Fill up A’ and ‘B.
(ii) Explain Co-extinction and Alien species invasion with suitable examples.
Answer:
(i) A-Habitat loss and fragmentation B – Over-exploitation.

(ii) Co-extinction – When a species becomes extinct, the plant and animal species associated with it also become extinct.
Eg plant and its pollinator, Host and its parasites.

Alien species invasion – New species introducing into a geographical region is called alien species. It cause decline or extinction of indigenous species.

Eg : – Nile Perch introduced into Lake Victoria in East Africa lead to extinction of Cichlid fish in the lake.

Question 20.
Explain the transformation experiments performed by Frederick Griffith with bacteria Streptococcus
Pneumoniae.
Answer:
Streptococcus pneumonia bacterium has two strains S strain cause Pneumonia. R strain did not cause Pneumonia.

Steps in Griffith’s experiment

S-strain Injected into mouse → Mouse dies of pneumonia.

R-strain → Injected into mouse → Mouse lives Heat killed S-strain → Injected into mouse → Mouse lives.
Heat killed S-strain + Live R-strain → Injected into mouse Mouse → dies

Griffith’s postulated that some ‘transforming principle’ transferred from the heat- killed S-strain to R-strain and make them virulent.