IGCSE Biology Paper-4: Specimen Questions with Answers 164 - 166 of 279

Passage

Carbon dioxide is a greenhouse gas.

Question 164 (2 of 2 Based on Passage)

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One Liner▾

Name one other greenhouse gas.

Explanation

Other greenhouse gas are Methane, Nitrous oxide, Fluorinated gases.

Passage

The figure below shows a section through a kidney.

Human Kidney

Question 165 (1 of 2 Based on Passage)

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Short Answer▾

Using label lines and the letters given, label the following on a copy of the figure:

X where filtration occurs

Y the renal artery

Z where urine passes to the bladder

Explanation

Human Kidney

Question 166 (2 of 2 Based on Passage)

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Short Answer▾

Name the processes resulting in the reabsorption of

  • glucose
  • water

Explanation

Selective Reabsorption

  • Discovered by Richard and supporters.
  • P. C. T. : P. C. T. is the pivotal site for reabsorption.

  • Glucose, amino acid and , ions are reabsorbed by active transport.

  • are reabsorbed by passive transport following the positively charged ions.

  • Active uptake of ions reduces the concentration of the filtrate and an equivalent amount of water passes into the peritubular capillaries by osmosis. (Here water is reabsorbed by passive transport. It is also known as obligatory water reabsorption) . Most of the important buffer bicarbonate is also reabsorbed from the filtrate. P. C. T. absorb nearly of filtered bicarbonate. Some urea is reabsorbed by diffusion. The rest remain in the filtrate for removed in the urine.