To maintain efficient aerobic respiration, mammalian cells must be continuously supplied with oxygen, and the waste product carbon dioxide must be rapidly removed. Which of the following describes the primary method by which carbon dioxide is transported in the blood from respiring tissues to the lungs?
As hydrogencarbonate ions (HCO3−HCO_3^-HCO3−) dissolved in the blood plasma
Directly dissolved as carbon dioxide (CO2CO_2CO2) gas molecules in the blood plasma
Bound to the iron-containing heme groups of hemoglobin molecules as carbaminohemoglobin
As carbonic acid (H2CO3H_2CO_3H2CO3) molecules accumulated within the cytoplasm of white blood cells
82 exam-style questions on OCR GCSE Biology 2.1 Supplying the cell, covering 2.1.1 Transport across cell membranes, 2.1.2 Mitosis and the cell cycle, 2.1.3 Importance of cell differentiation, and 2.1.4 Stem cells. Each one has a worked solution and a mark scheme showing where the marks go.