In a molecule of oxygen, two pairs of electrons are shared equally; such a bond is called a
What is nonpolar covelant bond
100
The molecule RNA contains the five-carbon sugar
What is Ribose
100
If a substance resists changes in pH, it is called
What is Buffer
100
What is the function of proteins?
What is metabolic regulation, movement, transport, support
100
Ions with a negative charge are called
What is anions
200
The best definition of organic material is anything that
What is contains carbon and hydrogen covalently bonded
200
Which of the following is unique to RNA?
A. glucose
B. ribose
C. phosphate group
D. deoxyribose
E. adenosine triphosphate
What is ribose
200
Which of the following substances would be nearest the pH of human blood?
A. white wine, pH = 3
B. tomato juice, pH = 4
C. urine, pH = 6
D. lemon juice, pH = 5.5
E. stomach secretions, pH = 2
What is Urine pH6
200
Proteins are composed of units called
What is amino acids
200
Which is a characteristic of carbon dioxide
What is it can pass easily through a cell membrane
300
What is a characteristic of hydrogen bonds?
What is Hydrogen bonds can form between neighboring molecules
300
A DNA nucleotide consists of
What is a deoxyribose sugar, a nitrogenous base, and a phosphate group
300
It is important to keep pH regulated because an imbalance in H+ concentration can cause
What is structural damage,
overactivation of enzymes.
unwanted chemical reactions.
deactivation of enzymes.
300
Molecules that perform most cellular "work" are called
What is proteins
300
Atoms of the same element but containing different numbers of neutrons are called
What is Isotopes
400
If two pairs of electrons are shared between two atoms, what type of bond occurs
What is a double covalent bond
400
The molecule DNA contains the five-carbon sugar
What is deoxyribose
400
Question 20
Marks: 1 Which of the following is sometimes used in diagnostic imaging?
A. a radioisotope.
B. an ion.
C. a proton.
D. a gamma ray.
E. an atom.
What is a radioisotope
400
What is the most abundant chemical compound in the human body?
What is water
400
The branch of science that deals with changes in molecules is
What is chemistry
500
Carbohydrate molecules may be used for which of the following?
A. the body's most important source of energy
B. receptors of the cell surface
C. part of nucleic acid structure
D. a primary energy storage molecule
What is all of them
500
The nucleic acid DNA
A. synthesizes lipids.
B. is double stranded.
C. contains the pentose ribose.
D. contains protein bases.
E. contains uracil in place of thymine
What is Double Stranded
500
All of the elements and compounds that are eaten and used by the body for some function are called
What is nutrients
500
A class of lipids used to signal cells to undergo changes is called
What is hormones
500
Lipids are used for which of the following?
A. help reduce body temperature
B. form essential structural components of cells
C. carry genetic information
D. provide roughly 10 times as much energy as carbohydrates
E. help protect the skeleton
What is form essential structural components of cells