1 Atoms and Molecules

What are the three fundamental subatomic particles that make up an atom?

Protons, Neutrons, Electrons

Where are protons and neutrons located within an atom?

Nucleus

Where are electrons located around the nucleus of an atom?

Shells or orbitals

What type of electrical charge does a proton have?

Positive

What type of electrical charge does a neutron have?

Neutral

What type of electrical charge does an electron have?

Negative

What is the dense, central core of an atom?

Nucleus

What two subatomic particles are found in the nucleus?

Protons and neutrons

What does the number of protons determine in an element?

Atomic number

What positively charged particles are located in the nucleus?

Protons

What electrically neutral particles are found in the nucleus?

Neutrons

What negatively charged particles orbit the nucleus?

Electrons

What regions surrounding the nucleus are electrons most likely to be found in?

Electron shells/orbitals

What is the smallest unit of an element that retains the chemical properties of that element?

Atom

How do atoms form molecules?

Chemical bonds

What do atoms share or transfer to form chemical bonds?

Electrons

What type of chemical bond forms when atoms share electrons?

Covalent bond

What type of chemical bond forms when atoms transfer electrons?

Ionic bond

What type of compounds contain carbon and are the foundation of living organisms?

Organic molecules

What roles do organic molecules play in living organisms?

Function, Energy storage, Structure

What are the four major classes of organic molecules found in living things?

Carbohydrates, lipids, proteins, nucleic acids

What do carbohydrates include?

Sugars and starches

What are the functions of carbohydrates?

Energy and structural support

What is the monomer of carbohydrates?

Monosaccharide

What is an example of a monosaccharide?

Glucose

What types of substances are included in lipids?

Fats, Oils, Waxes

What are the functions of lipids in living organisms?

Cell membrane structure, Energy storage, Insulation

What types of molecule is included in proteins?

Enzymes

What are the functions of proteins in living organisms?

Catalyzing reactions, Structural support, Molecule transport

What are proteins made up of?

Amino acids

What types of molecules are included in nucleic acids?

DNA and RNA

What is the main function of nucleic acids?

Carry genetic information

What fundamental particles came together to form protons and neutrons as the early universe expanded and cooled?

Quarks

What were the conditions like in the very early universe?

Extremely hot and dense

What happened to the universe’s temperature and size as it expanded?

Cooled and expanded

What is the central core formed by protons and neutrons in an atom?

Nucleus

What negatively charged particles were present in the early universe?

Electrons

Why could electrons not initially bind stably to nuclei in the early universe?

The universe was too hot

What happened as the universe cooled that allowed electrons to bind to nuclei?

Electrons combined with nuclei

What did electrons form when they combined with nuclei?

Neutral atoms

What is the process called when electrons combine with nuclei to form neutral atoms?

Recombination

What did recombination allow photons to do?

Travel freely

What faint afterglow of the Big Bang resulted from recombination?

Cosmic microwave background radiation

What determines the type of atom, or element?

Number of protons

How many protons does a hydrogen atom have?

One proton

How many protons does a helium atom have?

Two protons

What are three of the four major classes of organic molecules essential for life?

Carbohydrates, lipids, proteins

What are the four major classes of organic molecules also known as?

Biological macromolecules

What roles do biological macromolecules play in cells?

Cell structure and function

What do biological macromolecules make up a significant portion of?

Cell mass

What smaller organic molecules are linked together to form larger polymers?

Monomers

What are larger molecules formed when monomers are linked together?

Polymers

What are carbohydrates often called?

Sugars

What elements are carbohydrates composed of?

Carbon, oxygen, hydrogen

What is the characteristic ratio of carbon, hydrogen, and oxygen in carbohydrates?

1:2:1

What are examples of carbohydrates?

Glucose, fructose, starch

What are lipids commonly known as?

Fats and oils

What cellular structure that lipids form an important part of?

Cell membranes

Are lipids soluble in water?

No

What types of molecules are included in lipids?

Phospholipids, Triglycerides, Steroids

How are amino acids arranged in proteins?

Specific sequence

What types of molecules are included as examples of proteins?

Structural proteins, Hormone, Enzymes

What is an example of a structural protein?

Collagen

What are large organic molecules made of repeating smaller units called monomers?

Polymers

What are the smaller repeating units that make up polymers called?

Monomers

Which organic molecules are examples of polymers?

Carbohydrates and proteins

What process links monomers together to form polymers by releasing a water molecule?

Dehydration synthesis

What is released when monomers join together during dehydration synthesis?

Water molecule

What process breaks polymers down into monomers by adding a water molecule?

Hydrolysis

What is added when polymers are broken down during hydrolysis?

Water molecule

Why is carbon considered the central element in organic molecules?

It can form four covalent bonds

What do carbon’s four covalent bonds allow organic molecules to have?

Diverse structures and functions