Tips and Tricks of The Day

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Ex: Electrons from excited chlorophyll molecule of photosystem II are accepted first by:
(a) Cytochrome-b
(b) Cytochrome-f
(c) Quinone
(d) Ferredoxin
Explanation: Electrons from excited chlorophyll molecules of photosystem II are accepted first by quinine. Photosystem II is a photosynthetic pigment system along with some electron carriers that is located in the appressed part of the grana thyllakoids. Photosystem II has chlorophyll a, b and carotenoids. Other components of PS II are phaeophytin, plastoquinone (PQ), cytochrome complex and blue coloured copper containing plastocyanin.
Ex: Ureters act as urogenital ducts in
(a) Human males
(b) Human females
(c) Both female and male frog
(d) Male frog
Explanation: In male frogs the sperms are carried through the ureters, hence in male, ureters are called urinogenital ducts.
Ex: One of the synthetic auxin is
(a) IAA
(b) GA
(c) IBA
(d) NAA
Explanation: NAA is a synthetic auxin. Some of the most widely used weed killers are synthetic auxins. Synthetic auxin analogs include 1-naphthaleneacetic acid (NAA), 2,4-dichlorophenoxy acetic acid (2,4-D) and 2,4,5-trichlorophenoxy acetic acid (2,4,5-T).
Ex: Neck canal cells in Dryopteris are
A) One with two nuclei       
B) Two
C) One with one nucleus     
D) Four
Explanation: Neck is made up of 4 vertical rows of cells. Slightly curved and encloses on neck canal cell which is binucleated.
Ex: G0 state of cells in eukaryotic cell cycle denotes
A) Check point before entering the next phase
B) Pausing in the middle of a cycle to cope with a temporary delay
C) Death of a cell
D) Exit of cells from cell cycle
Explanation: When cells are not to divide after G1 phase and start undergoing differentiation into specific types of cells such cells are said to be in G0 phase/G0 state.
Ex: Auxetic growth is one in which there is
A) Increase in the fatty tissue only
B) Increase in the cell volume only
C) Increase in the cell number
D) Increase in the volume of the body due to the decrease in the inter-cellular material
Explanation: It is a rare type of growth and is found in a few nematodes (Ascaris), rotifers, tunicates (Herdmania) etc.
Ex: The plants growing in dark show yellowing in leaves and elongated internodes, this condition is called as
A) Etiolation
B) Chlorosis
C) Dechlorosis            
D) Dark effect
Explanation:  In Etiolation, chlorophyll (green) converts in protochlorophyll (yellow) in dark, etiolin hormone is formed due to which plants become                                   Dark
elongated. Chlorophyll(green) ⟷   Protochlorophyll(yellow) + 2H
Ex: The percentage of light energy utilized for photosynthesis by higher plants is
A) 100%      
B) 50%
C) 10%        
D) 1 to 2%
Explanation: Only 1-4% light is utilized in photosynthesis. In general rate of photosynthesis is more in intense light than diffused light.
Ex: Lichens indicate SO2 pollution because they
A) Show association between algae and fungi
B) Grow faster than others
C) Are sensitive to SO2
D) Flourish in SO2 rich environment 
Explanation: Lichens are very sensitive to air pollution, particularly to higher SO2 concentration in the atmosphere. This SO2 causes plasmolysis of algae cells and converts chlorophyll of algae into pheophytin by removing Mg. Phaeophytin results in chlorosis and death of lichen.
Ex: Which of the following pair is a combination of highest and lowest energy molecules?
A) Glucose and pyruvic acid
B) Palmitic acid and acetyl CoA
C) Glucose and maleic acid
D) Maleic acid and acetyl CoA
Explanation: Palmitic acid (one mole) on complete oxidation will produce 129 ATP molecules. Complete oxidation of one mole of acetyl CoA in TCA results in production of 12ATP molecules CO2 and H2O.