Which of the following statements abouthemoglobin isfalse?

	a.	hemoglobin is a very large protein composed of four largeprotein subunits
	b.	there are two alpha (α) and two beta (β) subunits in eachhemoglobin molecule
	c.	each alpha and beta subunit includes a heme group
	d.	oxygen (O2) molecules bind irreversibly to an ironion (Fe++) in a heme group

Which of the following statements about oxygendelivery to the body tissues isfalse?

	a.	low oxygen concentration in the body tissues enhances theunbinding of oxygen (O2) from hemoglobin
	b.	hemoglobin usually loses all four oxygens (O2) whenthey unbind in the tissues
	c.	body tissues have greater acidity (higher hydrogen ion(H+) concentration (lower pH) than the lungs
	d.	higher acidity (higher hydrogen ion (H+) causeshemoglobin to release more oxygen (O2

Digestion is necessary because…

		large biomolecules cannot pass through cell membranes
		the absorption of food requires energy (is endergonic)
		only monomers are absorbed through the lining of the smallintestine
		all except choice (b) are correct

Which of the following is not a typeof biomolecule that must be digested before it can be absorbed?

	a.	long-chain carbohydrate molecules
	b.	protein molecules
	c.	nucleic acid molecules
	d.	water-soluble vitamins

Which of the following is not afunction of human blood?

	a.	blood transports oxygen and nutrients to all body cells
	b.	blood transports carbon dioxide and other metabolic wastes fromcells
	c.	blood helps maintain the body’s internal pH and waterconcentration
	d.	blood exchanges gases with the atmosphere primarily through theskin

Which of the following statements about humanblood is false?

	a.	blood plasma makes up more than half of the volume of normalblood
	b.	blood plasma is mostly water, with dissolved ions, amino acids,glucose, hormones, proteins, and other materials
	c.	white blood cells (leukocytes) make up about 40% of the volumeof normal blood
	d.	red blood cells (erythrocytes) are the most common bloodcells