XII-Botany Karachi Board

BOTONY X-II
Q.1 (A). Fill in the blanks with the correct answers.
i. The potential energy of a water molecule is termed as _________.
ii. The loss of water in liquid form is called _________.
iii. The chromosomes which determine the sex are called _________.
iv. Gibberellin was first found in a fungus called _________.
v. Sclerenchyma cells are of two types, fibres and _________.
vi. The plants which develop flowers in fall and winter are called _________.
Q.1 (B). What is amitosis?
OR
Define Mitosis and give its significance.
OR
Define Meiosis and write the significance of Meiosis.
Q.1 (C). How and when does meiotic error take place?
OR
Define Sex Chromosomes and autosomes with examples.
OR
What is Syndrome? Give its different types. Explain any one of them.
OR
Define Calvin Cycle.
OR
Define Aerobic Respiration and Anaerobic Respiration.
Q.1 (D). DNA is a hereditary material. Prove it with examples.
OR
Define Meiosis. Describe different phases of Meiosis. Support your answer with accurate and labeled diagrams.
OR
Where do you find Mitotic and Meiotic Cell divisions in plant? Describe the various stages of Mitosis with suitable diagrams.
OR
Write the genetic explanation of the inheritance of the following traits.
i. Albinism in Humans
ii. Blood group in Humans
iii. Flower Colour in 4'o'Clock plant.
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Q.2 (A). Write "True" or "False" for the following statements.
i. Anaphase is the longest phase of mitotic division.
ii. The vegetative propogation involves the separation of a part of the parent plant.
iii. In formative phase, the division of cells is stopped.
iv. In Co-dominance, the two contrasting characters blend with each other.
v. Plants can be classified according to the availibility of water.
vi. The plant hormones are also influenced by environmental factors.
Q.2 (B). What do you understand by Karyotype and Test cross?
OR
Describe Parasitism and Symbiosis with examples.
OR
Define Genetic Code and Growth Point.
OR
Define vernalization and photoperiodism.
Q.2 (C). Write notes on the following.
i. Growth Correlations
ii. Osmoregulations
iii. Coniferous Forests
iv. Apoptosis
v. Deciduous Forests
Q.2 (D). How is sex determined? Explain sex linkage in drosophila.
OR
While working on pea plant in a cross Mendel observed a ratio 9:3:3:1. State the law, its procedure and prove the ratio.
OR
Describe Paratonic Movement in Plants.
OR
Briefly describe the Nastic Movement in plants.
OR
Explain the Law of Independent Assortment and prove it by making cross upto the second generation.
OR
Describe Mendel's Law of Segregation briefly.
Q.3 (A). Choose the correct answer from the given options
i. The movement of plant organs in response to touch stimulus is termed as
Chemotropism
Geotropism
Thigmotropism
Hydrotropism
ii. Plants growing in shades are termed as
Hydrophytes
Halophytes
Mesophytes
Sciophytes
iii. Is present is RNA but not in DNA
Adenine
Guanine
Cytocine
Uracil
iv. Parthenogenesis is a type of Reproduction which requires
One gamete
Two gametes
Two patents
No parent
v. The producer of a Pond Ecosystem is
Bacteria
Zooplankton
Phytoplankton
Fungi
vi. The study of living things in relation to its environment is called
Community
Ecosystem
Ecology
Succession
Q.3 (B). Describe the significance of Secondary growth.
OR
What are the adaptations in Xerophytes to conserve water?
OR
What are the reasons for the damage of DNA.
OR
Explain Racemose and Cymose inflorescence and give the various types of recemose inflorescence.
Q.3 (C). Differentiate between the following:
i. Auxin and Giberellin
ii. Incomplete Dominance and Co-Dominance
iii. Photoperiodism & Vernalization
iv. Transportation & Guttation
Q.3 (D). What is Orsmeregulation? Describe Osmeregulation in flowering plants in their natural habitat.
OR
What do you mean by Biomes? Name the different Biomes of the world and describe any two of them.
OR
What is Ecological Succession? Write in detail about the hydrosere.
OR
Describe Kreb's Cycle in detail.
Q.4 (A). Match the item of Column "A" with those of Column "B".
Column "A"
(i) Head or Capitulum
(ii) Terminalization
(iii) Plant Hormones
(iv) Double Fertilization
(v) Guttation
(vi) Topographic factor
Column "B"
(a) Hydathodes
(b) Endosperm
(c) Slope
(d) Diakinesis
(e) Sunflower
(f) Ethene
Q.4 (B) What is meant by Biological Clock and Circadian Rythum?
OR
Describe the process of Gene Expression in a cell.
OR
What do you mean by Rh factor. If a Rh negative woman marries a Rh positive man, what would be the result.
Q.4 (C). Define Plasmolysis. Write the internal and external factors affecting the rate of transpiration.
OR
Differentiate between Photosynthesis and Respiration?
Q.4 (D). What are the components of an Ecosystem? Explain Abiotic Factors.
OR
What is chromosomal aberration? Describe its various kinds and mention their effects.
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Q.5 (A). Fill in the blanks with the correct answers.
i. DNA is made up of billions of units called __________.
ii. All aquatic and terrestrial ecosystem collectively constitute __________.
iii. The break down of bigger rocks into fine smaller mineral particles is called __________.
iv. The frozen Sub-soil in Tundra is called __________.
v. For a trait a gene which has more allelic forms is called __________.
vi. A seed develops into a new plant as a result of __________.
Q.5 (B). What is Sporophyte?
OR
What are Meristematic tissues? Describe their various types in plants.
OR
What is the role of Pollen Tube?
OR
Write different phases of growth.
Q.5 (C). Define Ecological Levels of organization.
OR
Explain briefly cyclic and Non-Cyclic Photophosphorylation.
OR
Describe the process of Translocation of food in plants.
Q.5 (D). Give the pre and post fertilization changes in a dicot seed.
OR
Define Asexual Reproduction. Describe the various modes of natural and artificial methods of Asexual Reproduction found in flowering plants.