Biology
Given below is a diagram representing a stage during the mitotic cell division. Study the diagram and answer the following questions :
(i) Identify the stage by giving a suitable reason.
(ii) Is it a plant or an animal cell? Give a reason to support your answer.
(iii) Draw a neat, labelled diagram of the stage which follows the one shown in the diagram.
(iv) How many chromosomes will each daughter cell have after the completion of the above division ?
(v) Name the four nitrogenous bases.
Answer
(i) The stage represented in the diagram is Anaphase. In this phase the two sister chromatids of the chromosomes are pulled apart, towards the centrioles present at the opposite poles of the cell.
(ii) The cell is an animal cell because cell wall is absent and centrioles are present with asters.
(iii) Telophase follows Anaphase. Its diagram is shown below:
(iv) Each daughter cell will have four chromosomes.
(v) The four nitrogenous bases are:
- Adenine
- Guanine
- Cytosine
- Thymine
Related Questions
The diagram given below represents a system in the human body. Study the diagram and answer the following questions:
(i) Identify the system.
(ii) Label the parts marked 5 and 6.
(iii) Name the two hormones secreted by 1.
(iv) Mention the number and the name of the part involved in fertilization and implantation from the above diagram.
(v) Mention the surgical methods of contraception in :
- Human males.
- Human females.
Answer the following questions briefly :
(i) How are the cytons and axons placed in the brain and the spinal cord ?
(ii) Which part of the human ear gives 'Dynamic balance' and 'Static balance' to the body ?
(iii) Explain how the human eye adapts itself to bright light and dim light.
(iv) What is Parthenocarpy ? Give one example.
(v) Mention any two objectives of 'Swachh Bharat Abhiyan'.
Given below are two stages in the evolution of man. Study them and answer the questions that follow:
(i) Identify Australopithecus and Neanderthal man from the above pictures.
(ii) Mention two characteristic features each for the two stages.
(iii) Who proposed the theory of 'Natural Selection'?
(iv) Name the organism used as an example to explain 'Industrial Melanisum'.
(v) Give two examples of vestigial organs in humans.
In Mendel's experiments, tall pea plants (T) are dominant over dwarf pea plants (t).
(i) What is the phenotype and genotype of the F1 generation if a homozygous tall plant is crossed with a homozygous dwarf plant?
(ii) Draw a Punnett square board to show the gametes and offspring when both the parents are heterozygous for tallness.
(iii) What is the Phenotypic ratio and genotypic ratio of the above cross in (ii)?
(iv) State Mendel's Law of Dominance.
(v) What is a Dihybrid Cross?