BSC2085: Module 2
Define a steroid
A type of lipid
In regards to reaction rates, describe "catalysts"
ALWAYS speeds up reaction
Describe reversible reactions.
Can go in either direction under different circumstances. Symbolized by arrows going in both directions. Become irreversible if the end product is removed or used, which happens a lot in the body.
In regards to reaction rates, describe "concentration"
High concentration usually speeds up reaction
In regards to reaction rates, describe "temperature"
High temperature usually speeds up reaction
What are the types of chemical bonds?
Ionic, covalent (non-polar and polar), and hydrogen
Define anabolism (synthesis) reactions
building; requires energy
Which of the following is a molecule, but not a compound? a) H2O b) 2H c)H2 d) H+
c) H2
Which of the following is a functional group that is part of a building block of proteins? a) phosphate b) adenine c) amino d) ribose
c) amino
AB -> A+B is a general notation for a(n) ________ reaction. a) anabolic b) endergoncic c) decomposition d) exchange
c) decomposition
________ reactions release energy. a) catabolic b) exergonic c) decomposition d) catabolic, exergonic, and decomposition
c) decomposition
C6H12O6 is the chemical formula for a ________ . a) polymer of carbohydrate b) pentose monosaccharide c) hexose monosaccharide d) all of the above
c) hexose monosaccharide
What are the two types of chemical reactions?
Anabolism and catabolism
Describe polysaccharides
Long chains of glucose; examples are glycogen (in animals), starch (in plants), and cellulose (in plants, can't be digested)
Describe a non-polar covalent bond
equal sharing of electrons; no charge (Example: O=O) (Strongest)
What is energy and what are some of its forms?
The capacity to do work. 1) Heat 2) Light 3) Kinetic 4) Potential 5) Chemical
Uracil ________. a) contains nitrogen b) is a pyrimidine c) is found in RNA d) all of the above
d) all of the above
What are the properties of water that make it essential to life?
1) Solvency due to polar covalent bond and V-shaped molecule 2) Cohesion 3) Thermal stability
Describe pH
A measure of H+ ion concentration. A pH of 7.0 is neutral (H+ = OH-). A pH of less that 7 is acidic solution (more H+). A pH of greater than 7 is basic (alkaline) solution (more OH-)
What is an element?
A substance that cannot be broken down into simpler substance. Consists of atoms (ex. an atom of oxygen)
What is the most famous nucleotide in the body that is also used as energy "currency"in the body?
ATP
Mitochondria produce ________ through cellular respiration. This product is also the major energy currency of the cell.
Adenosine Triphosphate (ATP)
What is matter and what are its three states?
Anything that has mass and takes up space. 1) Solid 2) Liquid 3) Gas
What is an atom and what is it made up of?
Basic unit of a chemical element. Made of protons, neutrons, and electrons
What are the 4 categories of carbon compounds?
Carbohydrates, Lipids, Proteins, and Nucleotides and Nucleic Acid
Describe saturated fatty acids
Carbon atoms saturated with hydrogen
Describe phospholipids/ cell membrane composition.
Cell membrane is a phospholipid bilayer. 2 fatty acid "tails" are hydrophobic. These tails point away from ECF and ICF. The tails are non-polar. The phosphate "head" is hydrophilic. The head points towards ECF and ICF and is polar.
Describe proteins
Chain of more than 50 amino acids. Most abundant organic compound in the body. Peptide bonds hold the amino acids together.
Describe nucleic acids
Chains of nucleotides. The five nucleotides are A, T, C, G, U
What is a molecule?
Chemical particles composed of two or more atoms united in a chemical bond.
Describe disaccharides
Composed of two monosaccharides; Sucrose, Lactose; Maltose
What are reaction rates affected by?
Concentration, temperature, and catalysts
Describe unsaturated fatty acids
Contains carbon atoms that are not saturated with hydrogen (contains double or triple bonds between carbons)
Describe the nucleic acids
DNA (deoxyribonucleic acid) contains millions of nucleotides. Contains all of our genes. Uses A, T, C, G. RNA (ribonucleic acid). There are three types: messenger RNA, ribosomal RNA, and transfer RNA. Uses A, U, C, G.
What are the major elements of the body and at what percent of body weight are they?
Hydrogen, Oxygen, Nitrogen, and Carbon; 98.5%
Describe the attributes of a lipid.
Hydrophobic organic molecule. Insoluble in water. The primary types in humans are fatty acids, triglycerides, phospholipids, and steroids
What are the major anions in the human body?
Intracellular fluid: Phosphate Extracellular fluid: Chloride
What are the major cations in the human body?
Intracellular fluid: Potassium Extracellular fluid: Sodium
Define an electrolyte
Medical term for a salt in the blood or other bodily fluid. Electrolytes conduct electrical signals in the body.
What are compounds?
Molecules composed of two or more different elements. They are a type of molecule.
Describe cholesterol
Most important steroid. All other steroids are made from cholesterol.
Describe a Electron
Negative; found in circular clouds around the nucleus
Describe a Neutron
Neutral; found in the nucleus
Describe buffers.
Our bodies use buffers to resist changes in pH. The primary buffer is the bicarbonate buffer.
Describe a Proton
Positive; found in the nucleus
Describe enzymes
Proteins that function as biological catalysts. Lowers activation energy. "Proteins that do things"
Describe a base (alkali)
Proton (H+ ion) acceptor
Describe an acid
Proton (H+ ion) donor
Describe monosaccharides
Simpliest carbohydrates. The three important monosaccharides are glucose, fructose, and galactose.
Describe solutions
Solvent and solute mixed together. Solvent is usually water. Solute is particles that are in the solvent.
What is organic chemistry?
Study of compounds containing carbon.
Describe triglycerides
The most abundant lipid. Function as concentrated source of energy in the body.
Describe an ionic bond.
Transfer of electrons; results in two charged ions: Cation+ and Anion- (Example: Na+ Cl-)
When an atom donates an electron to another atom, it becomes________. a) an ion b) an anion c) nonpolar d) all of the above
a) an ion
Which of the following statements about chemical bonds is true? a) covalent bonds are stronger than ionic bonds b) Hydrogen bonds occur between two atoms of hydrogen c) Bonding readily occurs between nonpolar and polar molecules d) A molecule of water is unlikely to bond with an ion.
a) covalent bonds are stronger than ionic bonds
A phospholipid ________. a) has both polar and nonpolar regions b) is made up of a triglyceride bonded to a phosphate group c) is a building block of ATP d) can donate both cations and anions in solution
a) has both polar and nonpolar regions
What 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
a) hydrogen and hydrogen
The energy stored in a foot of snow on a steep roof is ________. a) potential energy b) kinetic energy c) radiant energy d) activation energy
a) potential energy
The characteristic that gives an element its distinctive properties is its number of ________: a) protons b) neutrons c) electrons d) atoms
a) protons
Which of the following is most likely to be found evenly distributed in water in a homogenous solution? a) sodium ions and chloride ions b) NaCl molecules c) salt crystals d) red blood cells
a) sodium ions and chloride ions
Define metabolism
all of the chemical reactions in the body
Describe a hydrogen bond
attraction between partial positive and negative charges; bonds that give molecules their three dimensional shape; shape of DNA and proteins between water molecules (Weakest)
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? a) Ty's blood is slightly acidic b) Ty's blood is slightly alkaline c) Ty's blood is highly acidic. d) Ty's blood is within the normal range
b) Ty's blood is slightly alkaline.
The smallest unit of an element that still retains the distinctive behavior of that element is an ________. a) electron b) atom c) elemental particle d) isotope
b) atom
What organic compound do brain cells primarily rely on for fuel? a) glucose b) glycogen c) galactose d) glycerol
b) glycogen
A pentose sugar is a part of the monomer used to build which type of macromolecule? a) polysaccharides b) nucleic acids c) phosphorylated glucose d) glycogen
b) nucleic acids
CH4 is methane. This compound is ________. a) inorganic b) organic c) reactive d) a crystal
b) organic; contains both carbon and hydrogen
A substance formed of crystals of equal numbers of cations and anions held together by ionic bonds is called a(n)________. a) noble gas b) salt c) electrolyte d) dipole
b) salt
The ability of an enzyme's active sites to bind only substrates of compatible shape and charge is known as ________. a) selectivity b) specificity c) subjectivity d) specialty
b) specificity
The bonding of calcium, phosphorous, and other elements produces mineral crystals that are found in bone. This is an example of a(n) _________ reaction. a) catabolic b) synthesis c) decomposition d) exchange
b) synthesis
Nitrogen has an atomic number of seven. How many electron shells does it likely have? a) one b) two c) three d) four
b) two
Define catabolism (decompisition) reactions
breaking down; releases energy
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 __________. a) about 80 neutrons b) fewer than 80 neutrons each c) more than 80 neutrons each d) more electrons than neutrons
c) more than 80 neutrons each To find, take the atomic number and subtract it from the mass number. This gives you 120.59 or more neutrons than protons.
A molecule of ammonia contains one atom of nitrogen and three atoms of hydrogen. These are linked with ______________. a) ionic bonds b) nonpolar covalent bonds c) polar covalent bonds d) hydrogen bonds
c) polar covalent bonds
A substance dissociates into K+ and Cl- in solution. The substance is a(n) ________ . a) acid b) base c) salt d) buffer
c) salt
In DNA, nucleotide bending forms a compound with a characteristic shape known as a(n) ________. a) beta chain b) pleated sheet c) alpha helix d) double helix
d) double helix
Together, just four elements make up more than 95 percent of the body's mass. These include ________. a) Calcium, magnesium, iron, and carbon b) oxygen, calcium, iron, and nitrogen c) sodium, chlorine, carbon, and hydrogen d) oxygen, carbon, hydrogen, and nitrogen
d) oxygen, carbon, hydrogen, and nitrogen
Chewing a bite of bread mixes it with saliva and facilitates its chemical breakdown. This is most likely due to the fact that ________. a) inside of the mouth maintains a very high temperature b) chewing stores potential energy c) chewing facilitates synthesis reactions d) saliva contains enzymes
d) saliva contains enzymes
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 is an example of a ________. a) solvent b) solute c) solution d) suspension
d) suspension
What is a chemical bond?
forces that hold molecules together or attract one molecule to another
Define a salt
ionic compound that dissolves in water into a cation and an anion
What is the pH of blood?
pH of blood ranges from 7.35 to 7.45.
Describe a polar covalent bond
unequal sharing of electrons; partial charge; within water molecule