chapter 6 assessment

what are the basic building blocks of all matter? A. electrons B. protons C. atoms D. molecules

C. atoms

which feature of water explains why water has high surfface tension? A. water deffuses into cells B. waters resistance to temp changes C. water is a polar molecular D. water expands when it freezes

C. water is a polar molecular

which of the following describes an isotope of the commonly occurring oxygen atom which has 8 electroons 8 protons and 8 neutrons A. 8 electrons 8 protons and 9 neutrons B. 7 electrons 8 protons 8 neutrons C. 8 electrons 7 protons and 8 neutrons D. 7 elec

A. 8 electrons 8 protons and 9 neutrons

which of the following will form a solution? A. sand and water B. oil and water C. salt and water D. salt and sand

C. salt and water

which of the following applies to a water molecular? A. water is a nonpolar molecular B. the atoms in water are bonded by ionic bonds C. the weak bond between two water molecurs is a covalent bond D. water molecures have a negativaly charged end and posit

D. water molecures have a negativaly charged end and positively charged end

which of the following carbohydrates is a plysaccharide? A. glucose B. fructose C. sucrose D. starch

D. starch

which of the following pair is unrelated? A. sugar - carbohydrerates B. fat- lipid C. amino acid- protein D. starch - nucleic acid

D. starch - nucleic acid

an acid is any substance the forms _____ in water A. hydroxide ions B. oxigen ions C. hydrogen ions D. sodium ions

C. hydrogen ions

which of these is not made up of proteins? A. hair B. enzymes C. fingernails D. cellulose

D. cellulose

which of the followin is not a smaller subunit of a nucleotide? A. phosphare B. nitrogen C. ribose sugar D. glycerol

D. glycerol

an enzyme _____ chemical reactions.

speeds

a calcium atom has 20 protons and _____ electrons

20

a _____ bond involves sharing of electrons.

covalent

the first energy level of an atom holds _____ electrons the second energy level holds 8 electrons

2

in a water molecule each ____ atom shares one electron with the single ____ atom

hydrogen, oxygen

a substance fits into an area of an enzyme called the ____

active site

hydrogen chlorine and sodium are examples of ______

elements

long chains of amino acids connected to each other by a _____ bond form a ______

peptide, protein

difgusion is the process in which molecules move from a ______ concentration to a _____ concentration

high, low

the positively charged ______ atoms of one water molecule attract the negativey charged ______ atom of another water molecule to form a hydrogen bond

hydrogen , oxygen