Saturday, March 16, 2013

Quantum yield of photosynthesis is 12.5%.

1.Sugar moves in phloem vessels as ______.
(a) cellulose
(b) glucose
(c) starch
(d) sucrose

Answer: (d) Glucose is called principle carbohydrate, sucrose is called translocable carbohydrate, starch is called storage carbohydrate and cellulose is called structural carbohydrate

2.______ ions help in photolysis of water.
(a) Mn++
(b) Mg++
(c) Cl-
(d) both (a) and (c)
Answer: (d) Magnoprotein is associated with photolysis of water, which contains Mn++ and Cl- as cofactor.

3.RUBISCO enzyme is also called as ______.
(a) carboxytetra mutase
(b) carboxydimutase
(c) carboxytrimutase
(d) carboxyunimutase
Answer: (b) RUBISCO is called marker enzyme of chloroplast since it can perform carboxylation as well as oxidation, therefore also called carboxydimutase.

4.______ is precursor for abscissic acid (ABA)
(a) Zeatin
(b) Lutein
(c) Violaxanthin
(d) Mevalonic acid
Answer: (c) Precursor for the biosynthesis of abscissic acid is violaxanthin, a type of xanthophyll found in leaves.

5.In young leaves ratio of carotene to Xanthophyll is ____.
(a) 2 : 1
(b) 3: 1
(c) 1: 3
(d) 1: 2
Answer: (d) In young leaves cuticle is thin hence require more production therefore concentration of Xanthophyll is more than carotene which is more protective

6.Which of the following pigments contains open pyrolle ring?
(a) Phycobilins
(b) Xanthophylls
(c) Chlorophylls
(d) β-carotene
Answer: (a) Chlorophylls are made of closed pyrolle, whereas Phycobilins are made of open pyrolle, Carotenoids are carbon hydrogen derivatives.

7.In which of the following light, rate of photosynthesis is maximum?
(a) white
(b) discontinuous white
(c) red
(d) blue
Answer: (b) Discontinuous white light or intermittent light don’t increase the temperature, hence the rate of photosynthesis is maximum.

8.Quantum yield of photosynthesis is ______.
(a) 13.5 %
(b) 8 %
(c) 13%
(d) 12.5%
Answer: (d) Quantum requirement of photosynthesis is 8 quanta, whereas quantum yield is 1/8 x 100 i.e., 12.5%

9.During light phase of photosynthesis ______ is oxidized and ______ is reduced.
(a) CO2 and Water
(b) Water and CO2
(c) Water and NADP
(d) NADPH2 and CO2
Answer: (c) During light phase water is oxidized and the released hydrogen is accepted by NADP, hence is reduced to NADPH2.

10.During dark phase of photosynthesis ______ is oxidized and ______ is reduced
(a) CO2 and Water
(b) Water and CO2
(c) Water and NADP
(d) NADPH2 and CO2
Answer: (d) During dark phase the reduced NADPH2 transfer its hydrogen to CO2 which is reduced to carbohydrate.

11.The visible product of photosynthesis is ______.
(a) glucose
(b) cellulose
(c) starch
(d) fructose
Answer: (c) Starch is visible product since it can be stained with iodine.

12.To produce 3 glucose molecules ______ ATP and ______ NADPH2 molecules are required.
(a) 54, 36
(b) 54, 30
(c) 36, 60
(d) 18, 12
Answer: (a) 1 glucose molecule requires 18 ATP and 12 NADPH2

13.Glycolytic reversal is a part of ______.
(a) aerobic respiration
(b) anaerobic respiration
(c) light phase of photosynthesis
(d) dark phase of photosynthesis
Answer: (d) First phase of calvin cycle is called glycolytic reversal, which is a part of dark phase of photosynthesis.

14.RuBp carboxylase acts as RuBp carboxygenase at ______ CO2 conc. And ______ O2 conc.
(a) low, low
(b) low, high
(c) high, high
(d) high, low
Answer: (b) During photorespiration RUBP carboxylase acts RUBP oxygenase under low CO2 High O2 concentrations.

15.The source of CO2 during calvin cycle in C4 plant is
(a) Malic acid
(b) OAA
(c) PEP
(d) RuDP
Answer: (a) During C4 pathway malic acid undergo decarboxylaton to release CO2.

16.Dicot which follow C4 pathway is____.
(a) wheat
(b) Amranthus
(c) Maize
(d) Mango
Answer: (b) Most of the C4 plant is monocot however exceptional dicot is Amaranthus.

17.Absorption spectrum of chlorophyll is maximum in _____ light.
(a) red
(b) blue
(c) yellow
(d) blue-violet
Answer: (b) Absorption spectrum of chlorophyll is maximum in blue light whereas action spectrum is maximum in red light.

18.The oxygen molecule in glucose formed during photosynthesis comes from
(a) Water
(b) Organic acids
(c) CO2
(d) atmosphere
Answer: (c) Since glucose is formed form CO2 and hydrogen released from water hence oxygen comes from CO2.

19.Dimorphic chloroplast are present in ______.
(a) zeamays
(b) sacchrum officinale
(c) sorghum bicolor
(d) all of these
Answer: (d) Dimorphic chloroplast or Kranz anatomy is the character feature of monocot, All the given options are monocot.

20.Red pigment in tomato is
(a) b-carotene
(b) Anthocyanin
(c) Lycopene
(d) Lutein
Answer: (c) the biological name of the tomato is lycopersicon esculentum it is due the ther lycopene.

21.Solarisation refers to ______.
(a) formation of sugar with help of water or energy
(b) destruction of chlorophyll
(c) synthesis of chl.
(d) both b and c
Answer: (b) Destruction of chlorophyll is due harmful light and oxygen called solarization.

22.Dark reaction requires light reaction for
(a) carboxylation of RUBP
(b) regeneration of RUBP
(c) reduction of PGA
(d) formation of hexose sugar
Answer: (c) Product of dark reaction is NADPH2 required for reduction of PGA to PGAL

23.Emerson effect proves
(a) concept of two photosystem in plant
(b) photophosphorylation
(c) photorespiration
(d) there are light and dark reaction in photosynthesis
Answer: (a) The concept of two photosystem in plant was proposed by emerson bases on red drop effect and enhancement effect.

24.Name a plant which do not perform photosynthesis is
(a) Algae
(b) Bryophyllum
(c) cuscutta
(d)Pitcher plant
Answer: (d) Cuscutta is a parasite.

25.Light reaction of photosynthesis results in formation of ______.
(a) O2
(b) NADPH + H+
(c) ATP
(d) All of these
Answer: (d) During light phase ATP and NADPH is product where as oxygen is byproduct produced during light phase.

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