Photosynthesis in Higher Plants

Which of the following statements about phytochrome is true?

• P_r absorbs yellow light and becomes P_fr

• P_r absorbs red light and becomes P_fr

• P_fr absorbs red light and becomes P_r

• P_fr absorbs yellow light and becomes P_r

Stomata opens

• in day time - for gaseous exchange

• in day time- no gaseous exchange

• in night time only - for gaseous exchange

• in night time only - no gaseous exchange

Photosynthetic bacteria do not contain

• quantasome

• PS- I and PS- II

• PS-II

• PS-I

Which of the following statements is correct regarding short day plants (SDPs)?

• They can flower in complete darkness if supplied with exogenous nutrients.

• They are the same as long day plants.

• They do not have a critical photoperiod

• All of these.

Photorespiration usually occurs in

• one cell organelle

• two cell organelles

• three cell organelles

• four cell organelles

Blackman's law is related to

• respiration

• transpiration

• root pressure

• photosynthesis

Assertion : Stomata remain open during day.

Reason : Stomata help in exchange of gases.

• If both Assertion and Reason are true and Reason is the correct explantion of Assertion

• If both Assertion and Reason are true and Reason is not the correct explanation of Assertion

• If Assertion is true but Reason is false

• If Assertion is false but Reason is true.

Assertion : The collenchyma is a thick walled living tissue.

Reason : The collenchyma is thickened due to the deposition of pectin.

• If both assertion and reason are true and reason is the correct explanation of assertion.

• If both the assertion and reason are true but reason is not the correct explanation of assertion.

• If assertion is true but reason is false.

• If both the assertion and reason are false.

The photorespiratory carbon-oxidation cycle involves the interaction of

• chloroplast

• mitochondria

• peroxisomes

• all of these

Who discovered photophosphorylation?

• Arnon et. al.

• Von Mayer

• Calvin et. al.

• Hill