biochemistry Flashcards
What is the charge of protons?
positive
What are the three subatomic particles that make up an atom?
protons neutrons and electrons
What is the charge of neutrons?
neutral (no charge)
What is the charge of electrons?
negative
What does the atomic number of an element tell you?
The number of proteins in an atom of that element. the number of protons equals the number of electrons
What does atomic mass tell you?
the number of protons + neutrons in an atom of that element
What is an atom?
the smallest unit of matter
What is an element?
a pure substance made up of only ONE type of atom
What is a molecule?
two or more atoms covalently bonded together
What is a compound?
atoms of two or more different elements joined together
What is the difference between an ion and an isotope?
An atom that loses or gains electrons becomes an ion. An atom that have more or less neutrons than usual is an isotope
What is the difference between a covalent bond and an ionic bond?
Covalent bonds form when atoms share electrons in order to become stable
Ionic bonds form when electrons are transferred from one atom to another in order for the atoms to become stable and the resulting ions are attracted to each other because of their opposite charges
Why do atoms form bonds?
Atoms form bonds in order to become stable. They are stable when their outer electron level is full
What is a hydrogen bond?
A hydrogen bond is a weak attraction between H and O in different water molecules (and in a few other types of molecules)
What is the difference between cohesion and adhesion?
cohesion is an attraction to the same type of molecule. Adhesion is an attraction to something different
How do surface tension and capillary action help living things?
Surface tension allows small organisms to move across bodies of water.. Capillary action moves water up from the roots to tree to the rest of the plant
Why is it important for living things that water takes a long time to heat up or cool down?
Our bodies are mostly water so it helps our bodies not get too hot or too cold. helps us maintain HOMEOSTASIS
Why is it important for living things that ice floats?
it keeps lakes and ponds from completely freezing in winter so all the organisms that live in the water can survive
Why is water called a universal solvent?
water can dissolve many different substancces
WHere on the pH scale are acids found? What type of ions is most concentrated in acids?
Acids are less than 7 on the scale. H+ (hydrogen ions) are concentrated in acids
Where on the pH scale are bases found? What type of ion is most concentrated in bases?
Bases are more than 7 on the scale. OH- (hydroxide ions) are concentrated in bases
WHat is the pH of a substance that is neutral? Give an example of a neutral substance
Neutral is 7 on the pH scale. Water is a neutral substance
WHat four elements make up 96% of any living thing?
CARBON, HYDROGEN, OXYGEN, AND NITROGEN
How can you tell if a substance is organic or not?
Organic compounds contain carbon
What are the monomers of carbohydrates, proteins, and nucleic acids?
Carbs: monosaccharides, Proteins: amino acids, Nucleic acids: nucleotides
What are the functions of carbohydrates?
quick energy or store energy
What are the functions of lipids?
store energy, cell membranes, insulation, protection
What are the functions of proteins?
body structure, speed up reactions (enzymes),
WHat are the functions of nucleic acids?
store genetic information, help make proteins
Why do living organisms need enzymes?
so that reactions can go fast enough to sustain life
Enzymes speed up reactions by reducing the ______?
Activation energy of a reaction (Which is the energy needd to start the reaction)