Exam 1 questions with answers

It takes one calorie of heat to raise the temperature of one gram of water one degree Celsius at sea level. This is referred to as the __________ of water A. specific heat B. heat of fusion C. homeostasis D. vaporization E. heat of transformation

Specific heat

Why is it advantageous for cells to be small?

a small cell has a small volume relative to surface area, thereby increasing efficient transport

The primary purpose of homeostasis is to: A. accept responses to stimuli B. provide unlimited growth within an organism C. allow unrestricted movement of an organism

maintain a constant internal environment

A molecule of a saturated triacylglycerol contains: A. a maximum number of double bonds between carbons in the fatty acid chains B. the maximum number of triple bonds between carbons in the fatty acid chains C. the maximum number of hydrogen atoms in the fatty acid chains D. fatty acid chains with both amino and carboxyl groups E. alternating single and double bonds between carbons in the fatty acid chains

the maximum number of hydrogen atoms in the fatty acid chains

How can we identify a particular element? A. By its number of protons B. By its number of electrons C. By its number of neutrons D. By its shape of valence shells E. By is amount of energy levels

By its number of protons

The smooth ER is the primary site for the synthesis of phospholipids and cholesterol needed to make____ A. DNA B. ATP C. Ribosomes D. hormones E. cell membranes

Cell membranes

What carbohydrate energy storage molecule is found in animal liver and muscle cells? A. starch B. cellulose C. gylcogen D. a fatty acid E. cholesterol

Glycogen

The ration of the size of the image seen with the microscope to the actual size of the object is called:

Magnification

Which is an example of a disaccharide? A. ribose B. glucose C. maltose D. fructose E. tricylglycerol

Maltose

What organic molecules is the primary structural component of cell membranes?

Phospholipids

What type of bond is formed if one atom is more electronegative than the other atom? A. covalent B. hydrogen C. polar covalent D. van der Waals E. non-polar covalent

Polar covalent

At which level of protein structure are peptide bonds most important? A. primary (covalent bonds) B. secondary (hydrogen bonds) C. tertiary D. quaternary E. globular

Primary

Nitrogen has an atomic number of seven. How many bonds does a N atom make?

Three

What is the purpose of molecular chaperones?

To assist the folding of other molecular proteins

The chemical behavior of an atom is determined most directly by the:

number of valence electrons

What is the difference between an electrically neutral atom and an ion?

An ion has an unequal number of protons and electrons, while a neutral atom has an equal number

What differentiates an organic compound from an inorganic compound?

An organic compound contains carbon

The primary difference between the amino acids commonly found in proteins is in their: A. R or variable groups B. number of potassium groups C. number of phosphate groups D. number of carbonyl groups E. Number of asymmetric carbons

R or variable groups

What is the purpose of the cilia and flagella of cells? A. They generate the cell's metabolism B. They provide movement for the cell C. They help maintain homeostasis D. They generate cell signaling E. They contract muscles

They provide movement for the cell

When we know what kinds of ____ are present in an organic compound, we can predict its chemical behavior. A. proteins B. enzymes C. triacylglycerols D. macomolecules E. functional groups

Functional Groups

When does an atom become an anion? A. it emits radiation B. it shares electrons C. it loses one or more electron D. it gains one or more electron E. one or more of its electrons changes energy levels

It gains one or more electrons

In living organisms, chemical reactions responsible for growth, repair, and nutrition are collectively referred to as: A. development B. metabolism C. adaptation D. genetics E. homeostasis

Metabolism

What two organelles are both responsible for converting energy into forms that can be used by cells? A. ribosomes and chloroplasts B. lysosomes and chloroplasts C. mitochondria and lysosomes D. mitochondria and peroxisomes E. mitochondria and chloroplasts

Mitochondria and Chloroplasts

Which process is MOST DIRECTLY associated with the theory of evolution? A. Populations changing over time B. Mutations changing the gene pool C. Production of large numbers of offspring D. Sexual reproduction producing variation in a population E. Competition between members of a population for limited resources

Mutation changing the gene pool

If a toxin, such as a bacterial toxin, destroys ribosomes, what cellular activity will be affected first? A. protein synthesis B. DNA synthesis C. Movement D. energy storage E. active transport

Protein synthesis

An organism that is Eukaryotic is by definition: A. is a protist B. is unicellular C. possesses a nucleus D. possesses organ systems E. belongs to domain Bacteria

possesses a nucleus

A base is defined as a(n)_____acceptor A. neutron B. electron C. proton D. anion E. cation

proton

What type of molecule carries the hereditary information of an organism?

DNA

which statement best summarizes the differences between RNA and DNA? A. RNA is a single stranded form of DNA B. DNA is a polymer and RNA is a monomer C. RNA is a protein and DNA is a nucleic acid D. DNA is the primary energy currency of all cells E. DNA comprises the genes, while RNA is a direct participant in the process of protein synthesis

DNA comprises the genes, while RNA is a direct participant in the process of protein synthesis

The covalent bond between a hydrogen atom and the oxygen atom in water is formed when: A. hydrogen gains an electron from oxygen B. hydrogen and oxygen share an electron pair C. hydrogen and oxygen both lose an electron from their outer shells D. hydrogen and oxygen both gain an electron from their outer shells

Hydrogen and Oxygen share an electron pair

Why can table salt (NaCl) dissolve easily in water?

The partial positive charge of the hydrogen's in the water can associate with the negative charge of the chloride ions, and the partial negative charge of the oxygen of the water molecule can associate with the positive charge of the sodium atom

An atom X contains 14 protons, 13 electrons, and 12 neutrons, and atom Y contains 14 protons, 14 electrons, and 12 neutrons. What can you conclude?

X and Y are atoms of the same element

Glucose and Fructose are_____because they have identical molecular formulas but their atoms are arranged differently. A. polar B. tertiary C. enatiomers (mirror) D. structural isomers E. geometric isomers

Structural isomers

Identify three of the five characteristics of life: 1. The cellular composition of life 2. The evolution of life 3. The interactions of living organisms 4. The mechanisms of disease 5. The transmission of information A. 1, 2, and 3 B. 2, 3, and 4 C. 3, 4, and 5 D. 1, 4, and 5 E. 2, 3, and 5

The evolution of life, The interactions of living organisms, and The transmission of information

which description illustrates an amphipathic moleculre? A. a phospholipid with two polar ends B. a phospholipid with two hydrophobic ends C. a phospholipid with only one hydrophilic end D. a phospholipid with only one hydrophobic end E. a phospholipid with both a hydrophobic end and a hydrophilic end

a phospholipid with both a hydrophobic end and a hydrophilic end

Which best statement describes an element? A. a substance that cannot burn B. a substance that is soluble in both acid and base C. a substance that is held together by covalent bonds D. a substance that is composed of more than one kind of atom E. a substance that cannot be broken into simpler substances by chemical reactions

a substance that cannot be broken into simpler substances by chemical reactions

What is a hydrolysis reaction?

A hydrolysis reaction is when one H20 molecule is add to break apart di/polysaccharides

A stalk of celery is placed in a solution of blue colored dye. After one hour, the leaves have blue fluid in their veins. Which property of water is being demonstrated? A. surface tension B. high specific heat C. Adhesion and cohesion D. evaporation and cooling E. lower density as a solid than as a liquid

Adhesion and cohesion

Which organic compound is not only responsible for energy storage, but also can provide thermal insulation? A. lipids B. proteins C. nucleic acids D. carbohydrates E. monosaccharides

Lipids

When a nucleic acid undergoes HYDROLYSIS, the resulting subunits are: A. fatty acids B. amino acids C. nucleotides D. carotenoids E. monosaccharides

Nucleotides

When tissues organize, what do they form? A. a cell B. a nucleus C. an atom D. an organ E. an enzyme

an organ

What represents the most basic level of chemical organization? A. cell B. atom C. tissue D. molecule E. organism

atom

What is an isotope?

atoms with the same number of protons but different number of neutrons

Which description illustrates the primary structure of a protein molecule? A. bonding of two amino acids to form a dipeptide B. folding of a peptide chain to form a alpha helix C. association of several polypeptide chains by weak bonds D. order in which amino acids are joined in a peptide chain E. Three dimensional shape of an individual polypeptide chian

bonding of two amino acids to form a dipeptide

Isotopes differ from each other with respect to the number of: A. protons only B. electrons only C. neutrons only D. both protons and electrons E. both neutrons and protons

neutrons only

A DNA molecule is made up of: A. lipids B. proteins C. nucleotides D. fatty acids E. carbohydrates

nucleotides

Which is a property of unsaturated fats? A. they are more common in animals B. they are generally liquid at room temperature C. They have no double bonds in the carbon chains of their fatty acids D. they have fewer fatty acids per fat molecule than do saturated fats E. they contain more hydrogen than do saturated fats having the same number of carbon atoms

they are generally liquid at room temperature