Topic B Flashcards
Any living material that is composed of atoms and takes up space
Matter
Elements required in large amounts and make up the majority of living cells
Bulk elements
What are the four most abundant elements in living cells?
Carbon, hydrogen, nitrogen, and oxygen
Elements that are required in living systems but in small amounts
Trace elements
Give two examples of trace elements
Iron and zinc
How are elements identified?
By the number of protons
An atom’s nucleus contains
Protons and neutrons
What charge do protons have?
Positive charge
What charge do neutrons have?
Neutral (no charge)
What charge do electrons have?
Negative charge
The atomic number of an atom is determined by what?
The number of protons
Atoms can gain or lose charge. An atom with a charge is a what?
Ion
When does an ion have a positive charge?
When electrons are lost
When does an ion have a negative charge?
When electrons are gained
The mass number of an atom is
The number of protons + the number of neutrons
What is the difference between an atom and an element?
An atom is the smallest unit of matter. An element is a substance made up of only one type of atom.
What are atoms called that have different number of neutrons?
Isotopes
What is a radioactive isotope?
An isotope that emits energy as rays or particles when they break down into more stable forms
What is a molecule?
Two or more atoms joined together (can be atoms of the same or different elements)
What ions impact the pH of solutions?
Hydrogen ions
pH7=
Neutral
pH<7=
Acidic
pH>7=
Alkaline
What are the biological or organic molecules?
Carbohydrates, proteins, nucleic acids, and lipids
What are monomers?
Small molecules (subunits) that are the fundamental building blocks of larger molecules
What are polymers?
A chain of subunits (monomers) held together by chemical bonds
Carbohydrate monomers are called
Monosaccharides and disaccharides
What are examples of carbohydrate monomers?
Glucose, fructose, and galactose
Carbohydrate polymers are called
Polysaccharides
What are examples of carbohydrate polymers?
Complex carbohydrates; cellulose, chitlin, starch, and glycogen
What are the functions of carbohydrates?
Quick energy/store energy, support cells, and structural support
What are amino acids?
Monomers of proteins
What are polypeptides?
Polymers of proteins
What is the function of proteins?
Carries out nearly all of the work of the cell
What are nucleotides?
Monomers of nucleic acid
What are examples of nucleotides?
Adenine, thymine, cytosine, guanine, uracil
What are the polymers of nucleic acids?
DNA and RNA
What is the function of nucleic acids?
Store and use genetic information and transmit it to the next generation
Do lipids have monomers and polymers?
No! Lipids have three different subunits.
Triglycerides
Glycerol and three fatty acid chains; store energy
Steroids
Carbon chains and rings; stabilize animal membranes, sex hormones
Phospholipids
Glycerol, two fatty acid chains, and phosphate; form a major part of biological membrane
