General Biology Review Flashcards

A comprehensive set of 148 Question and Answer flashcards covering core biology topics from cellular organization, chemistry of life, biomolecules, cell structures, and organelles based on lecture notes.

What is the basic unit of structure and function of all living things?

Cell

What is a union of two or more atoms of the same or different elements?

Molecule

What are the levels of biological organization?

Atom → Molecule → Cell → Tissue → Organ → Organ System → Organism → Species

What is a group of interbreeding organisms?

Species

What are organisms of the same species living in a particular area called?

Population

What are interacting populations in a particular area called?

Community

What is a community plus its physical environment called?

Ecosystem

What are the regions of Earth (land, water, and atmosphere) inhabited by living organisms called?

Biosphere

What are the chemical reactions that occur in a cell called?

Metabolism

What process converts solar energy into the chemical energy of carbohydrates?

Photosynthesis

What does DNA stand for?

Deoxyribonucleic Acid

What is an adaptation?

Any modification that makes an organism better able to function in a particular environment.

What is the change in a population that makes organisms better suited to their environment?

Evolution

What is it called when organisms with beneficial traits are more likely to pass those traits to offspring?

Natural Selection

What is the study of naming and defining groups of organisms?

Taxonomy

What is the study of evolutionary relationships among organisms?

Systematics

Name the classification categories in order.

Species → Genus → Family → Order → Class → Phylum → Kingdom → Supergroup → Domain

What is the scientific method?

A step-by-step process used to test hypotheses and explain observations.

What is the loss of the last member of a species called?

Extinction

What is an atom that gains or loses an electron called?

Ion

What are the positively charged subatomic particles located in the nucleus?

Protons

What are the neutral subatomic particles located in the nucleus?

Neutrons

What are the negatively charged subatomic particles moving around the nucleus?

Electrons

Which subatomic particle has a positive charge?

Proton

Which subatomic particle has a neutral charge?

Neutron

Which subatomic particle has a negative charge?

Electron

What is the number of protons in the nucleus of an atom called?

Atomic Number

What is the sum of protons and neutrons in an atom's nucleus called?

Mass Number

What are atoms of the same element with the same number of protons but different numbers of neutrons called?

Isotopes

Who developed the periodic table?

Dmitri Mendeleev

What is the outermost electron shell of an atom called?

Valence Shell

What determines the chemical reactivity of an atom?

Valence Electrons

What is a molecule containing two or more different elements called?

Compound

What type of bond forms through the transfer of electrons from one atom to another?

Ionic Bond

What is a cation?

An atom that loses an electron and becomes positively charged.

What is an anion?

An atom that gains an electron and becomes negatively charged.

What type of bond forms when two atoms share one or more pairs of electrons?

Covalent Bond

What covalent bond shares electrons equally?

Nonpolar Covalent Bond

What covalent bond shares electrons unequally?

Polar Covalent Bond

What is the ability of an atom to attract electrons in a chemical bond called?

Electronegativity

What is a hydrogen bond?

A weak attraction between a slightly positive hydrogen atom and a slightly negative atom.

When is a hydrogen bond weak?

When only a single hydrogen bond is present.

When is a hydrogen bond strong?

When multiple hydrogen bonds are present.

What is the function of hydrogen bonds?

To maintain the proper structure and function of molecules such as proteins and DNA.

True or False: Hydrogen bonds allow water to absorb large amounts of thermal energy.

True

What is water's ability to cling to itself due to hydrogen bonding?

Cohesion

What is water's ability to cling to other polar surfaces?

Adhesion

What is the measure of hydrogen ion concentration in a solution?

pH

What substances release hydrogen ions ($H^+$) in water?

Acids

What substances accept hydrogen ions or release hydroxide ions in water?

Bases

What keeps pH within a specific range?

Buffers

What is a hydrolysis reaction?

A chemical reaction in which water is added to break a covalent bond.

What is a molecule that speeds up a chemical reaction?

Enzyme

What are carbohydrates?

An energy source composed of carbon, hydrogen, and oxygen in approximately a $1:2:1$ ratio.

What are monosaccharides?

Single sugar molecules.

What are disaccharides?

Two monosaccharides joined together through a dehydration reaction.

What are polysaccharides?

Polymers of monosaccharides.

What is starch?

The primary energy-storage carbohydrate in plants.

What is glycogen?

The primary energy-storage carbohydrate in animals.

What is cellulose?

A structural polysaccharide found in plant cell walls.

What is chitin?

A structural polysaccharide found in fungal cell walls and animal exoskeletons.

What is peptidoglycan?

A structural component found in bacterial cell walls.

What are lipids?

Large nonpolar molecules that are insoluble in water.

What are the four major classes of biomolecules?

Carbohydrates, lipids, proteins, and nucleic acids.

What is an organic molecule?

A molecule containing both carbon and hydrogen atoms.

What are functional groups?

Clusters of specific atoms attached to a carbon skeleton that determine chemical reactivity and polarity.

What determines the chemical reactivity and polarity of organic molecules?

Functional groups.

What is a carbon skeleton (backbone)?

The carbon chain of an organic molecule.

What are isomers?

Molecules with the same molecular formula but different arrangements of atoms.

Why is carbon able to form many different molecules?

Because it can form four covalent bonds and create chains, branches, and rings.

What is a monomer?

A repeating subunit that makes up larger molecules.

What is a polymer?

A molecule composed of many monomers linked together.

Which biomolecule is NOT considered a polymer?

Lipids.

What is a dehydration reaction?

A reaction that joins monomers together by forming a covalent bond and releasing water.

What is the purpose of a dehydration reaction?

To build polymers from monomers.

What is the purpose of a hydrolysis reaction?

To break polymers into monomers by adding water.

What role do enzymes play in dehydration synthesis and hydrolysis?

They speed up the reactions without being consumed.

What is the monomer of carbohydrates?

Monosaccharide.

What is the polymer of carbohydrates?

Polysaccharide.

What is the monomer of proteins?

Amino acid.

What is the polymer of proteins?

Polypeptide.

What is the monomer of nucleic acids?

Nucleotide.

What are the two major nucleic acids?

DNA and RNA.

What are hexoses?

Six-carbon sugars such as glucose.

What are pentoses?

Five-carbon sugars such as ribose and deoxyribose.

What sugar is commonly called blood sugar?

Glucose.

What sugar is commonly called fruit sugar?

Fructose.

What sugars make up lactose?

Glucose and galactose.

What sugars make up sucrose?

Glucose and fructose.

What sugars make up maltose?

Two glucose molecules.

What enzyme breaks down lactose?

Lactase.

What are the main functions of lipids?

Long-term energy storage, insulation, protection, cell communication, and structural support.

What are triglycerides?

Lipids made of one glycerol molecule and three fatty acids.

What is an unsaturated fatty acid?

A fatty acid containing one or more double bonds.

What is a saturated fatty acid?

A fatty acid with no carbon-carbon double bonds.

Unsaturated fats are usually solid or liquid at room temperature?

Liquid.

Saturated fats are usually solid or liquid at room temperature?

Solid.

What is the primary function of phospholipids?

Forming cell membranes.

Which part of a phospholipid is hydrophilic?

The phosphate head.

Which part of a phospholipid is hydrophobic?

The fatty acid tails.