Test 2

The energy stored in the bonds of the molecules in the foods that humans eat is 1. a form of kinetic energy; 2. a form of potential energy; 3. referred to as chemical energy.

2&3

The initial energy "investment" needed to start a chemical reaction in a cell is called the

Activiation Energy

Water is important in the body because: - It is an excellent solvent and suspending medium. - It participates in hydrolysis and dehydration synthesis reactions. - It lubricates. - It helps to maintain homeostasis because it has a high heat capacity and high heat of vaporization. - All choices are correct

All choices are correct

Which type of chemical reaction breaks larger reactants into smaller products?

Decomposition

Which type of chemical reaction will absorb more energy than it releases?

Endothermic/ Endogonic

Which term is defined as the capacity to do work?

Energy

AB + CD → AD + BC is a general example of a(n) _____ reaction.

Exchange

Ions are nonpolar molecules

False

The non-polar tails of phospholipids create a water-soluble barrier.

False

Inorganic and organic compounds differ in that: -Inorganic compounds usually contain carbon -Inorganic compounds usually lack carbon -Inorganic molecules are usually large and complex - Inorganic molecules are used by the body to form complex functions

Inorganic compounds usually lack carbon

An enzyme acts to:

Lower the activation energy needed to start the reaction.

Blood is a complex body fluid. If a vial of blood is drawn for a blood test and is allowed to sit in a rack for some time, the red blood cells will settle out and drift to the bottom of the tube. This process indicates that at least as far as the blood cells are concerned, blood has the properties of what type of fluid?

Suspension

Which type of chemical reaction combines reactants to produce larger products?

Synthesis

Carbohydrates are a polar molecule.

True

Lipids are insoluble in water because they are nonpolar.

True

Phospholipids are both polar and non-polar.

True

Water is polar because the electrons spend more time near the oxygen molecule.

True

A chemical reaction involves interactions between the _____ of two different atoms.

Valence Electrons

Which is not true about pH? - pH is representative of the concentration of hydrogen ions - pH can indicate the acidity or alkalinity of a substance - if the pH of a solution changes from 7 to 6, this indicates a 10 fold increase in hydrogen ions - pH 7 is the midpoint of the scale and indicates equal amounts of hydrogen and hydroxide ions - a solution with a pH of 9 is acidic

a solution with a pH of 9 is acidic (higher numbers are basic and lower numbers are acidic)

A solution with a pH value less than 7 is

acidic.

The negative oxygen in water will interact with which of the following ions? -Methane -Sodium -Chlorine -All of the above

all

Phospholipids are -nonpolar -polar -self-interacting -all

all of the above

A chemical compound that helps control the pH of a solution by adding or removing hydrogen ions is a(n)

buffer.

Which of the following substances has a pH closest to 7.0?

cerebrospinal fluid

A solute that readily dissolves in water is

hydrophilic

Which is not a property of water? -it is a solvent -it is a lubricant -it participates in catabolic and anabolic reactions -it is a nutrient -it has a low heat capacity

it has a low heat capacity (Water actually has a high heat capacity

Which of the following is not a polar molecule? - water - sodium chloride - ATP - methane

methane

When table sugar, sucrose, dissolves in water, the water is the

solvent

In the body fluid compartments found in of the human body, the solvent is

water

What is the most abundant and most important inorganic compound in the body?

water