Sub. code 2021
NEB — GRADE XII
Model Question
Class 12 Biology Model Question
The candidates are required to give their answers in their own words as far as practicable. The figures in the margin indicate full marks.
Pass Marks : 32
सबै प्रश्नको उत्तर दिनुहोस् । (Attempt All Questions)
This model question paper is for Class 12 Biology, (subject code 2021), carrying full marks of 75 with a pass mark of 32, to be completed within 3 Hours. Model answers are available for questions that have one — reveal them with a free account (a few reveals) or a paid plan (unlimited).
Group A (Botany)
Rewrite the correct option of each question in your answer sheet
What type of development of an embryo from an unfertilized egg is called?
Parthenocarpy
Parthenogenesis
Polyembryogeny
Polycarpy
Which one of the following parts is not responsible for transpiration in plants?
Root
Stem
Leaves
All aerial parts
Which type of mutation is caused by the addition or deletion of a single nitrogenous base?
Transition
Transversion
Frame shift
Substitution
What basis would you apply to distinguish a meristematic tissue from a permanent tissue?
Supporting plant
Providing food
Activating cell division
Losing ability of cell division
Some of the $C_4$ plants possess diagnostic features of Kranz anatomy. Select which of the following plant contains such features?
Wheat
Maize
Barley
Oats
Group B (Botany)
Give short answer to the following questions.
Define vascular bundle. What type of vascular bundle is present in monocot root? Mention any two functions of vascular bundle.
Study the given figure carefully and answer the following questions.
Identify the given figure.
Name the parts A to D.
State the function of part D.
If you are assigned to make a Watson and Crick model of DNA, what essential components do you apply to make the exact structure of the DNA?
Assuming you are provided seeds for germination, which influencing parameters you need to follow for normal germination? What would happen when seeds are kept in low temperature
Biotechnology is an emerging discipline in this era. Would you think it can be used to mitigate the problem of food scarcity in context to Nepal? Justify your opinion.
Group C (Botany)
Long answer question
Three German biochemists Embden, Meyerhof and Parnas (EMP) worked out a pathway which involved the formation of pyruvic acid from a glucose molecule. Identify this pathway. Name the site where this pathway takes place in a cell. Construct a step by step pathway developed by them. List the net gain of ATP in this pathway.
Semi-conservative mode of DNA replication is the most common mode of replication which results in two identical daughter DNA molecules. Explain various enzymes and mechanism involved during this process with necessary diagrams
“Genes are inherited in new combination due to crossing over in the gametes”. Interpret this statement with its mechanism and necessary diagrams. Assess its significance also.
Group A (Zoology)
Rewrite the correct answer in your answer sheet.
Which of the following tissue lacks blood supply?
Areolar
Muscular
Bone
Cartilage
In frog, coelom is derived from which embryonic layer?
Ectoderm
Mesoderm
Endoderm
Mesoglea
What kind of enzyme is needed for digestion of milk protein in human beings?
Rennin
Lactase
Pepsin
Sucrase
Which one of the following sets contains the bacterial disease only?
Hepatitis, influenza, cholera
Cholera, typhoid, candidiasis
Tuberculosis, typhoid, cholera
Tuberculosis, cholera, candidiasis
If the cerebellum of a person gets injured, it will have effect on which of the following physiological function?
Respiratory ability
Body movement
Memory function
Smelling power
Vas deferens transport spermatozoa from cauda epididymis to ejaculatory duct. What happens when the vas deferens of a male is surgically disconnected?
Sperms become non-motile
Sperms lack nuclei
Seminal fluid is without sperms
No spermatogenesis occurs
Group B (Zoology)
Give the short answer to the following questions.
Define blastulation. Write down the process of blastulation during the development of frog.
What is immunity? Explain its type.
Study the given figure carefully and answer the following questions.
Identify the gland.
Where is it located?
Mention any two hormones secreted by it.
Compare and contrast areolar and adipose connective tissue.
Peer pressure plays a negative role in provoking smoking habits in adolescents. As a school captain, plan any two activities you would like to organize with the help of senior students and any other two activities you would like your school authorities to organize for the students to tackle this problem.
Group C (Zoology)
Give long answer to the following question.
Why typhoid is called enteric fever? Illustrate its causative agent, mode of transmission, symptoms and preventive measures.
A human being usually takes complex foods in her/his diet. However, our body needs its simpler form. Describe how the complex foods are converted into simpler forms within alimentary canal. Draw it with a well labeled diagram of alimentary canal. What would happen in digestion if the gall bladder is removed surgically?
On oxidation of glucose in the cells, $CO_2$ is released as a by-product. This CO2 is carried to the lungs for elimination. Explain how the transport of take place in human body? What is the role of carbonic anhydrase enzyme? Mention the significance of diaphragm in breathing?
Paper Overview & Analysis
Year
Model Question
Type
75
Full Marks
32
Pass Marks
3 Hours
Duration
27
Question Items
Question Type Breakdown
Group Breakdown