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Explore Class 12 Biology past and model questions by chapter, year, marks and question type.
178 questions found
Discuss the advantages and disadvantages of organ transplantation.
Candidiasis also known as moniliasis is an infection which affects immune compromised people. Describe its causative agent, modes of transmission, symptoms and preventive measures. Why is candidiasis common in diabetic patients?
Identify the given figure and name the parts labeled by A and B.
A plant species has chromosomes. A mutant plant is found to have chromosomes. Identify the type of chromosomal mutation and, on this basis, differentiate between aneuploidy and euploidy.
Describe the internal structure of a monocot root with diagrammatic figure.
Why is part B called mixed gland?
Adrenal glands also known as suprarenals are located above the kidneys and have outer cortex and inner medulla region. Name the different groups of hormones secreted by the different regions of adrenal cortex. Mention specific functions of each. Describe the disorders of hormones secreted by adrenal cortex.
Which of the following are psychotropic drugs?
Opiates
Antihistamines
Mescaline
Bhang
What is called the process in which the shrinkage of protoplasm of fresh plant cell kept in hypertonic solution?
Deplasmolysis
Endosmosis
Imbibition
Plasmolysis
What is the specific term used for the part of the plant that provides the root system?
Propagule
Stock
Callus
Scion
Tendons connect muscles to bones. Why are they less elastic in nature?
They contain more elastin fibres
They contain more collagen fibres
They contain less collagen fibres
They contain more reticular fibres
Which of the following describes the transmission of an X-linked trait from a father to his grandson through his normal carrier daughter?
Co-dominance
Maternal inheritance
Y-Linked inheritance
Criss-cross inheritance
Label the parts A and B.
A gardener removes the apical bud of a coffee plant to promote lateral branching. Which hormonal change best explains this effect?
Reduced auxins allows lateral buds to grow
Increased gibberellin causes stem elongation
Increased auxin induces dormancy
Increased auxins stimulates lateral buds
Which of the following tissue of a leaf helps in photosynthesis?
Aerenchyma
Xylem
Mesophyll
Sclerenchyma
Which vaccine is prepared using DNA-recombinant technology and contains only a specific antigen, reducing adverse reactions?
BCG
OPV
Hepatitis B
Rabies
A 17-year old student can read books comfortably but cannot clearly see the letters on black or white board. What could be the defect and its cause?
Hypermetropia due to short eyeball
Myopia due to increased focal length
Myopia due to elongated eyeball
Presbyopia due to weak ciliary muscles
Coronary sinus collects deoxygenated blood from myocardium (muscles) of heart. It drains blood into which chamber?
Left atrium
Right atrium
Left ventricle
Right ventricle
What is the space between the somatic and visceral layer of mesoderm called in the embryonic development of frog?
Blastocoel
Archenteron
Coelom
Neurocoel
What is the function of part A and C?