Chemical Basis of Life

Multiple Choice

Which has a positive charge?

• neutron

• electron

• tron

• proton

Multiple Choice

Which has a neutral charge?

• proton

• electron

• neutron

• tron

Multiple Choice

Which has a negative charge?

• proton

• electron

• isotope

• neutron

Multiple Choice

Matter composed of one type of atom:

• isotope

• ion

• element

• mixture

Multiple Choice

What is the smallest unit of matter?

• Orbital

• Cloud

• valence

• Atom

Multiple Choice

What is made of atoms of different elements bonded together?

• Elements

• Compounds

• Mixtures

• Quarks

Multiple Choice

What is the smallest amount of energy needed for reactants to form products called?

• Kinetic Energy

• Activation Energy

• Potential Energy

• Thermal Energy

Multiple Choice

Which type of reaction absorbs heat and causes a cooling effect?

• Exothermic

• Endothermic

• Combustion

• Neutralization

Multiple Choice

In an endothermic reaction, the energy of the products is ______ than the energy of the reactants.

• lower

• higher

• equal

• none of the above

Multiple Choice

Which of the following is an example of an exothermic reaction?

• Melting ice

• Lighting a candle

• Evaporating water

• Photosynthesis

Multiple Choice

An exothermic reaction releases heat and causes a ______ effect.

• cooling

• warming

• neutral

• none of the above

Multiple Choice

Enzymes are an example of

• Lipids

• Carbohydrate

• Protein

• Nucleic Acid

Multiple Choice

What is the purpose  of an enzyme?

• give permission for the reaction
• raise activation energy
• speed up reactions
• control how many reactions occur

Multiple Choice

Each enzyme only has 1 substrate that will fit its active site.  What is this called?

• reusable
• catalyst
• specific
• fragile

Multiple Choice

Any substance that is acted upon by an enzyme is called a(n)?

• Coenzyme
• Substrate
• Vitamin
• Polypeptide

Multiple Choice

Letter D...

• active site
• enzyme
• substrate
• products

Multiple Choice

Letter B...

• active site
• enzyme
• substrate
• products

Multiple Choice

Letter C...

• active site
• enzymes
• substrate
• products

Multiple Choice

Letter E...

• active site
• enzyme
• substrate
• products

Multiple Choice

Enzymes provide a site where reactants called substrates can be brought together in an enzyme-catalyzed reaction. The site is called the

• enzyme substrate complex.
• reaction site.
• active site.
• lock and key.

Multiple Choice

An enzyme speeds up a reaction by

• lowering the activation energy.
• raising the activation energy.
• releasing energy.
• absorbing energy.

Multiple Choice

Based on the graph, what is the optimal temperature for this enzyme? 

• 15^oC
• 40^oC
• 30^oC
• 35^oC

Multiple Choice

What makes an enzyme substrate specific?

• Size
• Shape
• Name
• Location it is found in

Multiple Choice

At high temperatures enzyme activity declines because of:

• Denaturation
• Decreased Kinetic Motion
• Increased H-Bonding
• Dissociation of Ionic Compounds

Multiple Choice

Enzymes are composed of which of the following monomers? 

• amino acids
• carbohydrates
• nucleotides
• monosaccharides

Multiple Choice

What is a Cataylst?

• A substance that speeds up a rate of chemical reaction.
• Molecules that make enzymes work harder and faster 
• reaction of an enzyme
• A substance that slows down a rate of chemical reaction.