Write one function of each of the following five parts of the human eyeball: [1 × 5 = 5]
(a) Cornea
(b) Lens
(c) Choroid
(d) Vitreous humour
(e) Retina
OR
Mention three changes occurring during the Anaphase stage of mitosis in an animal cell. Write the names of any two structural parts of the eukaryotic chromosome. [ 3 + 2 = 5]
| Part | Function |
|---|---|
| Cornea | Refracts (bends) light entering the eye onto the lens. |
| Lens | Focuses light rays onto the retina for clear vision. |
| Choroid | Provides nutrients to the retina through its dense network of blood vessels. |
| Vitreous humour | Maintains the shape of the eyeball and supports the retina by filling the posterior cavity with a gel-like substance. |
| Retina | Converts light into electrical signals that are sent to the brain for visual processing. |
Or
Here are three changes occurring during the Anaphase stage of mitosis in an animal cell in very short points:
Here are the names of two structural parts of the eukaryotic chromosome in very short points:
More WBBSE Moderate level questions
Explain the following three significances of cell division- Growth Repair Reproduction Tabulate the site of occurrences of meiotic cell division in the living world. [3+2=5] OR Explain the process of micropropagation. Distinguish between asexual and sexual reproduction on the basis of the following three features - No. of Parental organisms Cell Division Origin of variation [2+3=5]
Match the words in column-A with the most appropriate words in column B and re-write the correct pair mentioning the serial no. of both columns COLUMN - A COLUMN - B 1. Meninges (a) Decrease in the number of digits in the legs 2. Sexual reproduction (b) Submergence of islands 3. Roller tongue (c) Centromere 4. Evolution of the horse (d) Telomere 5. Environmental problem of Sundarban (e) Protects brain and spinal cord from mechanical injury 6. Attaches chromosome with spindle fibre (f) Controlled by autosome (g) Occurs through the production of gametes and their union
Explain the process of segmentation with the help of a proper example of plants.
Mention any two phenomena during G1 phase of Interphase.
Write two features of Amitotic cell division.
Explain the following two terms: Ganglia and Synapse.
The two reflex actions, namely sneezing and coughing help in avoiding danger – justify the statement.
What is the relation between the lens and the accommodation of the eye?
Cell division becomes uncontrolled if the function of checkpoints becomes hampered
Write the name of the chemical constituents of eukaryotic chromosome with the help of a table. What happens to a cell when the cell loses control at different points in cell cycle on division ? [3+2=5] OR What events occur during Anaphase stage of mitotic cell division ?Show the steps of sexual reproduction of flowering plants with the help of word diagram. [3+2=5]
Write one function each of the following five parts of a neuron: [1×5=5] (a) Dendron (b) Axon (c) Myelin Sheath (d) Schwann Cell (e) Node of Ranvier Or Write one function each of the following five parts of an eukaryotic chromosome: [1×5=5] (a) Chromatid (b) Centromere (c) Nucleolar Organizer (d) Satellite (e) Telomere
Draw a scientific diagram of neuron and label the following parts: [3+2=5] (a) Dendron (b) Myelin Sheath (c) Schwann Cell (d) Node of Ranvier OR Draw a scientific diagram of eukaryotic chromosome and label the following parts: [3+2=5] (a) Centromere (b) Satellite (c) Nucleolar Organizer (d) Telomere
