Module 1: ch 2 review A&P

Together, just four elements make up more than 95percent of the body's mass. These include ________

1) oxygen 2) carbon 3) hydrogen 4) nitrogen

On the periodic table of the elements, mercury (Hg) has an atomic number of 80 and a mass number of 200.59. It has seven stable isotopes. The most abundant of these probably have

About 80 neutrons each.

Which of the following is a functional group that is part of a building block of proteins?

Amino. The amino functional group is found within the building blocks of proteins called amino acids. this functional group possesses a nitrogen atom which is bonded to two atoms of hydrogen and the carbon skeleton.

The smallest unit of an element that still retains the distinctive behavior of that element is an

Atom.

Which of the following statements about chemical bonds is true?

Covalent bonds are stronger than ionic bonds.

AB → A + B is a general notation for a(n) ________reaction.

Decomposition

In DNA, nucleotide bonding forms a compound with a characteristic shape known as a(n)

Double helix. Pentose sugar of one monomer of nucleic acid bonds with a phosphate group of other monomer by dehydration synthesis reaction to form a backbone from which nitrogenous bases protrude. Two of these backbones attach in DNA at the protruding bases through hydrogen bonding to form a double helix.

What organic compound do brain cells primarily rely on for fuel?

Glucose. Most of the cells of the body can use a few other organic compounds besides glucose for fuel but nerve cells present in the brain can only use glucose as fuel for energy. ATP is produced when glucose is broken down for energy. More ATP is produced when oxygen is present which supplies energy to the brain cells.

Which of the following is a molecule, but not a compound? a. H2O b. 2H c. H2 d. H +

H2

Which of the following combinations of atoms is most likely to result in a chemical reaction? a) Hydrogen and hydrogen b) Hydrogen and helium c) helium and helium d) neon and helium

Hydrogen and hydrogen. Hydrogen contains only one electron present in the single electron shell. having only one electron results in a half filled electron shell which will be likely drawn to undergo a chemical reaction so that it can get stabilized.

A pentose sugar is a part of the monomer used to build which type of macromolecule?

Nucleic Acids. Nucleotides are arranged into nucleic acids. the nucleic acids, DNA and RNA both contain a pentose sugar that accounts for the difference between these two nucleic acids. DNA and RNA are nucleotides both containing a ribose but DNA lacks one oxygen atom then the RNA.

CH 4 is methane. This compound is

Organic compound. defined as substances which possess both hydrogen and carbon. Compounds with living organisms are synthesized through covalent bonds. Methane contains both carbon and hydrogen.

A molecule of ammonia contains one atom of nitrogen and three atoms of hydrogen. These are linked with________.

Polar covalent bonds.

The energy stored in a foot of snow on a steep roof is

Potential energy

The characteristic that gives an element its distinctive properties is its number of

Protons. The properties of an atom depend on its atomic number which is defined as total proton number present in nucleus of that atom. Atomic number is responsible for the identification of an element.

Chewing a bite of bread mixes it with saliva and facilitates its chemical breakdown. This is most likely due to the fact that ________.

Saliva contains enzymes. Saliva is secreted by salivary glands and is mainly composed of water but also contains enzymes, electrolytes, mucus, glycoproteins and other constituents. Enzymes present in saliva facilitate the chemical breakdown of bread which contains carbohydrates. An enzyme called salivary amylase facilitates this chemical breakdown.

A substance formed of crystals of equal numbers of cations and anions held together by ionic bonds is called a(n)

Salt.

A substance dissociates into K + and Cl - in solution.The substance is a(n)

Salt. salts are compounds formed from the acid base neutralization reaction. these dissociate into ions except hydroxyl or hydrogen ions when dissolved in water. Bases make solutions more alkaline whereas acids make them more acidic. Product of salts is an electrically neutral compound.

The ability of an enzyme's active sites to bind only substrates of compatible shape and charge is known as

Specificity. only one type of chemical reaction is catalyzed by a given enzyme and this characteristic of enzymes is called specificity as a substrate with specific electrical charge and shape is going to bind to the active site which is corresponding to that particular substrate.

Jenny mixes up a batch of pancake batter, then stirs in some chocolate chips. As she is waiting for the first few pancakes to cook, she notices the chocolate chips sinking to the bottom of the clear glass mixing bowl. The chocolate-chip batter is an example of a

Suspension. defined as a heterogeneous mixture in which a substance that is heavier gets settled out of the solvent over time. it is suspended in a liquid temporarily before getting settled out.

Nitrogen has an atomic number of seven. How many electron shells does it likely have?

Two. Atomic number determines the electrons present in an atom.Nitrogen atom has 7 atomic number and hence, there are 7 electrons. Shell one of the atom hold 2 electrons and shell two holds 5 electrons.Thus, Nitrogen atom is likely to have Two electron shells

Ty is three years old and as a result of a "stomach bug"has been vomiting for about 24 hours. His blood pH is 7.48.What does this mean?

Ty's blood is slightly alkaline. The normal range of pH is 7.35 to 7.45 of blood.A slightly alkaline pH can reduce the acidity of blood which can cause some serious disorders if homeostasis is not balanced and maintained.

Uracil

Uracil is a nucleobase of ribonucleic acid represented by the letter "U". in RNA, it binds via two hydrogen bonds to adenine. During the process of transcription, uracil replaces thymine and pairs with adenine. Uracil is a base containing nitrogen present in RNA and is also a pyrimidine.

________ reactions release energy.

decomposition.

A phospholipid

has both polar and nonpolar regions. The phospholipid bond is generated when a glycerol is bonded to two chains of fatty acid. The remaining third site of glycerol is bonded with a phosphate group that is attached to the region called the polar head region of the molecule. The fatty acid part is nonpolar of phospholipid compound and is hydrophobic.

C6H12O6 is the chemical formula for a

hexose monosaccharide. Glucose is one of the most important monosaccharides required by all human cells as its fuel. Glucose contains 6 carbon atoms called hexose sugar.

When an atom donates an electron to another atom, it becomes an

ion

Which of the following is most likely to be found evenly distributed in water in a homogeneous solution? a. sodium ions and chloride ions b. NaCl molecules c. salt crystals d. red blood cells

sodium ions and chloride ions. Positively charged sodium ions and negatively charged chloride ions get distributed evenly in water because of polarity of water molecules. Sodium and chloride ions get spontaneously dissolved and distributed in water.

The bonding of calcium, phosphorus, and other elements produces mineral crystals that are found in bone.This is an example of a(n) ________ reaction.

synthesis.