Plus One Botany Improvement Question Paper Say 2018

Kerala Plus One Botany Improvement Question Paper Say 2018 with Answers

Time: 1 Hour
Cool off time: 10 Minutes
Maximum Marks: 30

General Instructions to candidates

• There is a ‘cool off-time’ of 10 minutes each for Botany and Zoology in addition to the writing time of 1 hour each. Further, there is a ‘5 minutes’ ‘preparatory time’ at the end of the Botany Examination and before the commencement of the Zoology Examination.
• Use the ‘cool off time’ to get familiar with the questions and to plan your answers.
• Read the instructions carefully.
• Read questions carefully before you answering.
• Calculations, figures and graphs should be shown in the answer sheet itself.
• Malayalam version of the questions is also provided.
• Give equations wherever necessary.
• Electronic devices except non-programmable calculators are not allowed in the Examination Hall.

Answer all questions from question numbers 1 to 4. Each carry 1 score. (4 × 1 = 4)

Question 1.
Fill in the blank.
Small disc-shaped structures at the surface of the centromere are called …………
Answer:
Kinetochore

Question 2.
Observe the relationship between first two terms and fill in the blank.
C₄ plants : PEP case
C₃ plants : ………….
Answer:
RUBISCO

Question 3.
Which one of the following features are applicable to bacteriophages?
a) They are bacterial viruses.
b) They have double stranded DNA as genetic material.
c) The protein coat is called capsid.
i) a and b  iii) b and c
iii) a and c  iv) All of these
Answer:
iv) All of these

Question 4.
Choose the CORRECT answer.
All tissues on the inner side of the endodermis together constitute.
a) Conjunctive tissue
b) Stele
c) Pericycle
d) Vascular bundle
Answer:
b) Stele

Answer any 7 questions from question numbers 5 to 13. Each carries 2 scores. (7 × 2 = 14)

Question 5.
The following figures A and B shows two different types of phyllotaxy.

Identify the phyllotaxy A, B and explain them.
Answer:
A – opposite b – whorled
A – a pair of leaves at each node
B – more than two leaves at each node

Question 6.
Observe the given stage of mitosis

Identify the stage and write any two features of it.
Answer:
Telophase

• Nuclear envelope assembles around the chromosome clusters.
• Nuclear membrane, Nucleolus and E.R. repears

Question 7.
The element is said to be deficient when present below the critical concentration. What is critical concentration? State any two kinds of deficiency symptoms shown by plants.
Answer:
The element is said to be deficient when present below the critical concentration. Hence plant growth is retarded

• Chlororsis – leaf yellowing
• Necrosis – death of tissues

Question 8.
Match the items of column A with column B

Answer:
a) prothallus – Thalloid gametophyte of pteridophytes
b) protonema – Gametophyte of mosses
c) antheridium – Male sex organ of bryophytes
d) Gemmae – Asexual buds in liverworts

Question 9.
Observe the following pathways of anaerobic respiration.

Identify the products A and B. Give an example of organism in which any of these products are formed.
Answer:
A – lactic acid
B – ethanol

• Ethanol is produced by Yeast
• Lactic acid is produced by lactobacillus

Question 10.
Observe the T. Sofa plant part given below.

Identify the plant part and explain any two features of its vascular bundles.
Answer:
Dicot stem

• Cortex is heterogenous
• Vascular bundles are arranged in ring shape

Question 11.
The opening and closing of stomata is aided by the peculiarities of bean shaped guard cells. Mention any two such peculiarities.
Answer:
In guard cell, inner wall is thick and outer wall is thin and elastic
Microfibrils in guard cell are radially oriented than longitudinally

Question 12.
Observe the figure given below.

Fill in the blanks A, B, C and D with appropriate terms from the box given below.

Answer:
A – FeS
B – UQ
C – Cyt b
D – Cyt C

Question 13.
Amides contain more nitrogen than the aminoacids.
Name two important amides found in plants and explain their formation.
Answer:
Asparagine – It is formed from aspartic acid. In this, replacing of hydroxyl group by amino group
Glutamine – It is formed from glutamic acid. In this, replacing of hydroxyl group by amino group

Answer any 4 questions from question numbers 14 to 18. Each carries 3 score. (4 × 3 = 12)

Question 14.
The nucleoplasm contains small spherical shaped structures.
a) Name the structures
b) Name the openings seen in nuclear envelope and state their function.
Answer:
a) Nucleolus
b) Nuclear pores
It act as passage for the movement of RNA and proteins

Question 15.
There are certain seeds which fails to germinate even under favourable external conditions. This is called seed dormancy.
a) State any two reasons for seed dormancy.
b) Suggest two man made measures for breaking seed dormancy
Answer:
a) Seed dormancy occurs,

• Due to impermeable seed coat
• Due to the presence of inhibitory chemicals

b) Application of gibberellic acids
Seed coat can be broken by mechanical abrasives like sandpaper

Question 16.
Arrange the following events in the appropriate boxes.
a) Formation of ATP and NADPH₂.
b) Only photosystem I is functional.
c) Formation of ATP only
d) Both photosystem I and photosystem II are involved.
e) Splitting of water
f) No oxygen release

Answer:

Question 17.
Based on the symmetry, the flowers can be classified into three types. Name and explain them.
Answer:
1. Actinomorphic
When a flower can be divided into two equal radial halves in any radial plane passing through the centre, it is said to be actinomorphic.
2. Zygomorphic
When it can be divided into two similar halves only in one particular vertical plane, it is zygomorphic.
3. Asymmetric
A flower cannot be divided into two similar halves by any vertical plane passing through the centre.

Question 18.
Name and explain the structure of cell organelle that is involved in photosynthesis.
(Hint: Write four structural features)
Answer:
Chloroplast

• It is double membrane bound structure
• It consists of grana and stroma
• It consists of ribosomes and circular DNA
• It consists of chlorophyll pigments

Plus One Botany Previous Year Question Papers and Answers