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Refer to the given food web and select the incorrect option regarding it.


A V, W, X and U serve as top consumers in the given food web.
B The energy transferred from Q to U may be equal to or higher than the energy transferred from T to U.
C There are 12 food chains in the given food web, out of which 4 food chains have four trophic levels and rest have 3 trophic levels.
D Q, R, S and T are herbivores in the given food web.

In an artificial kidney machine, which of the following passes from the blood to the dialysis fluid?

A Glucose
B Plasma proteins
C Red blood cells
D Urea

Refer to the given flow chart and select the incorrect option regarding it.


A If P is tap root, then it could be turnip whereas if P is adventitious root, then it could be Dahlia.
B If Q is water hyacinth, then it propagates by offsets whereas if Q is Colocasia, then it propagates by rhizome.
C R could be Bryophyllum or Kalanchoe that propagates through adventitious buds that develop in the marginal notches of leaves.
D P could be sweet potato, Q could be mint and R could be Begonia.

Choose the Venn diagram which best illustrates the three given classes :

"Yak, Zebra, Deer"

(A)

(B)

(C)

The given photomicrograph shows the transverse section of two blood vessels, X and Y connecting the heart and the lungs.

Identify the blood vessels and select the incorrect statement regarding them.

A Blood vessel X connects right ventricle of heart with lungs.
B Blood vessel Y connects lungs with left atrium of heart.
C Blood in X contains higher percentage of oxygen as compared to blood in Y.
D X is pulmonary artery that carries deoxygenated blood from heart to lungs whereas Y is pulmonary vein that carries oxygenated blood from lungs to heart.

The given graph shows net uptake and net release of oxygen by a plant kept in open over a 24 hour period.
Which of the following holds true regarding the given graph?


A At 0800 hour, the oxygen taken up by plant in respiration is equal to oxygen released by it during photosynthesis.
B Plant is respiring throughout the 24 hour period but it is photosynthesising only between 0600 hours to 1800 hours.
C Assuming that the plant has the same respiration rate throughout 24 hour period, 70 mg of oxygen is produced by plant at 1600 hour.
D The highest rate of photosynthesis occurs at 1200 hour.

Rahul took a turmeric paper and tried to draw flowers on it with the help of cotton buds dipped in solutions P and Q. The flower drawn with solution P was not visible while the one drawn with solution Q. turned red.
Solutions P and Q. could be respectively

A Lime water and lemon juice
B Vinegar and soap solution
C Common salt solution and baking soda
D Both B and C.

Which of the following statements are incorrect?
I. Decomposition reactions are generally carried out by heating or by passing electricity.
II. An oxidising agent removes hydrogen from other substance.
III. In precipitation reactions, two substances react in solid state to form a soluble product.
IV. Precipitation and neutralisation reactions are examples of single displacement reaction.

A I and III only
B III and IV only
C II and IV only
D All of these.

The details of a 12 hour journey of a car is given here.

Given that average speed of the car is 60 km h^–1.
What is the value of x?

A 120 km
B 180 km
C 240 km
D 720 km

The lengths of the mercury thread in a thermometer immersed in pure melting ice and in pure boiling water are 6 cm and 22 cm respectively. What is the temperature of a solution if the length of mercury thread is 14 cm in the solution?

A 50 K
B 273 K
C 323 K
D 373 K