State whether the following actions are ‘voluntary action, simple reflex or
conditioned reflex:
1) Blinking
2) Cleaning the table
3) Playing on the keyboard
4)Salivating when food is put in the mouthGiven below is an apparatus used to study a particular process in plants. Study the same and answer the questions which follow:
(i) Name the apparatus.
(ii) Mention one limitation of this apparatus.
(iii)Which phenomenon is studied with the help of this apparatus?
(iv)What is the function of the part marked ‘Reservoir’?
(v) What is the role of the air bubble in the experiment?Given below is the diagram of the human ear. Study the same and answer the questions which follow:
(i) Give the biological term for the part labelled ‘A’ and state its function.
(ii) Name the part labelled ‘B’ and state its function.
(iii)Name the part labelled ‘C’ and state its function.
(iv)Give the function of ear wax.Given below is an experiment, set up by a candidate, to study the process of respiration in plants. The candidate failed to get the expected result as two mistakes were made while setting up the experiment.
(i) Identify and state the two mistakes made by the candidate.
(ii) What is the role of soda lime in the experiment?
(iii)What is the purpose of using lime water in flasks ‘A’ and ‘B’?
(iv)Give the chemical equation to represent the process of respiration.(i) Draw a neat and well-labelled diagram of the chloroplast.
(ii) List the events taking place in the photo-chemical phase of photosynthesis.
(iii)If you are planning an experiment to show the effect of light on photosynthesis:
1) Will you select white light or green light? Justify your answer.
2) Why would you select a destarched plant?(i) Structure of the chloroplast:
(ii) The photochemical phase of photosynthesis is light dependent. A series of chemical reactions occur in quick succession initiated by light; therefore, the phase is called the photochemical phase. It takes place in the chlorophyll-containing thylakoids of the chloroplast.
It occurs in the following steps:
1) Activation of chlorophyll: On exposure to light, chlorophyll becomes excited and absorbs photons (a photon is the smallest unit of light energy) to get activated.
2) Photolysis of water: The energy absorbed is used to split water molecules into hydrogen ion (H+) and hydroxide ion (OH−). During which 4 electrons are released.
3) Production of the reducing agent: NADP, i.e. Nicotinamide dinucleotide phosphate is reduced to NADPH.
4) Formation of molecular oxygen: Hydroxide ion is oxidised to hydrogen peroxide which decomposes to form molecular oxygen (O2). Molecular oxygen is released during photosynthesis.
5) Photophosphorylation: Electrons are used to convert ADP (adenosine diphosphate) into an energy-rich compound ATP.
(iii)
1) I would choose white light because photosynthesis is maximum in white light,
while it is minimum in green light as green light is reflected by green plants.
2) I would select a destarched plant because during the experiment, any starch
formed in the leaf will indicate that the starch is synthesised by the plant
during photosynthesis by using light.
Given below is a diagrammatic representation of a defect of the human eye.
(i) Identify the defect.
(ii) Mention two reasons for the above defect.
(iii)State how the defect can be rectified.
(iv)Name the part of the eye responsible for maintaining the shape of the eyeball.Name the hormones which lead to the following conditions:
(i) Diabetes mellitus
(ii) Growth of beard in women
(iii)Myxoedema
(iv)Gigantism
(v) Exophthalmic goitreStudy the diagram given below and then answer the questions which follow:
(i) Name the parts labelled 1 and 2. State the function of each part.
(ii) State any one function of amniotic fluid.
(iii)What is the role of the umbilical cord in the development of the foetus?
(iv)Name the part in the diagram which is endocrine in nature.