Chapters 1 + 2 (BIO 103)

This flashcard set reviews Chapters 1 and 2 of the Understanding Biology Textbook. Exam 1 will be on Sept. 23, 2026.

What is the Linnaean System?

A system of classification used to classify living organisms.

What is the common acronym used in the Linnaean System?

Did King Philip Come Over For Great Sandwiches?

How are living organisms named in the Linnaean System?

They are named using binomial nomenclature.

What are the three domains (or forms of life)?

Bacteria, Archea, and Eukarya.

Which of the three domains are prokaryotic?

Bacteria and Archea.

Which of the three domains are eukaryotic?

Eukarya.

What are the kingdoms of Eukarya?

Plantae, Fungi, Animalia, and Protists.

Which kingdom of Eukarya has no common ancestor, is unicellular, and is also eukaryotic?

Protists.

What are the few properties that living and non-living things have in common?

Complexity, movement, and response to stimuli.

What are the 5 fundamental properties of life?

Cellular Organization, Energy Utilization, Homeostasis, Growth-Reproduction-and Development, and Heredity.

What is the full hierarchal organization of life (include all aspects)?

Atoms, molecules, macromolecules, organelles, cells, tissues, organs, organ systems, organism, population, species, community, ecosystem, and the biosphere.

What are emergent properties and how do they form?

Emergent properties are properties that occur due to complexities that arise in the structural hierarchy of living systems.

What is inductive reasoning?

Concept → General Principle.

What is deductive reasoning?

General Principle → Concept

What is the scientific method and its steps?

Scientific Method is a process used by both researchers and scientists to test hypotheses and gain information and insight. (Steps include: Observation, Hypothesis, Experiment, Data Analysis, and Conclusion).

What is hypothesis?

A testable prediction in the scientific method.

What are variables?

Factors that may influence the outcome of an experiment.

What is an independent variable?

What you change in an experiment (like time). It acts as the "cause" in an experiment. Its value does not change based on other variables in the study.

What is a dependent variable?

The data that you measure. It acts as the "effect" or outcome. Its value "depends" on the independent variable.

What is an experiment?

Procedure created to test a hypothesis utilizing the independent variable and dependent variable as well as a control, test group, and hypothesis.

What the control group?

Group with variable held constant to observe the effects of the variable of interest.

What is data?

Information collected from the experiment to help lead to the conclusion or falsification and restart of the scientific procedure.

What is a theory (2 definitions)?

1.) an excepted proposed explanation (deductive) from a natural phenomenon made by general principles

2.) interconnected concepts supported by inductive scientific reasoning and experimental evidence to explain an area of study.

What are biological models?

Models used to explain scientific concepts and how the working pieces fit together. Organize how we think about a problem.

What is reductionism?

Evaluate a system by reducing to working parts.

What is descent with modification?

Common ancestor and environmental or societal influences change aspects of the organism.

What is natural selection?

Nature takes its course choosing favorable traits.

What are the three evidences of evolution?

Fossil Record, Comparative Anatomy (Analogous + Homologous), and Molecular Evidence.

What are the 5 unifying concepts of biology?

Life is subject to chemical and physical laws, structure determines function, life transforms energy and matter, living systems depend on information transactions, and evolution is an explanation for the unity and diversity of life.

What are atoms?

extremely small particles that make up matter.

What are elements?

substances that cannot be further broken down by ordinary chemical means.

What are protons, neutrons, and electrons?

Protons: Inside the nucleus and (+) charge.

Neutrons: inside the nucleus and ( )/no charge.

Electrons: Outside of nucleus and (-) charge.

What is the atomic number?

The atomic number of an element is directly equivalent to the amount of protons inside the atoms’ nucleus of the element.

What is the periodic table?

“A visual presentation of all of the elements arranged based on atomic number, configuration of electrons, and chemical properties. This was first proposed by the chemist Dmitri Mendeleev” - Textbook Definition.

What information is shown on the periodic table for each element?

You can find an element’s atomic number, atomic mass, and valence electrons on the periodic table.

What are isotopes?

Isotopes are atoms of an element with the SAME Protons and DIFFERENT NUMBER OF NEUTRONS.

What are radioisotopes?

Radioactive isotopes emit various types of energy as they decay. These isotopes are usually unstable, so the nucleus tends to break up into elements with smaller atomic numbers. That breakup is what emits energy, also known as radioactive decay - which is constant.

How can we treat cancer with isotopes (hint: radiation).

We can treat cancer with isotopes by using it to tag specific molecule and follow its progression. In cancer, we are able to identify tumors based on imaging that shows areas that did not take up radioactive iodine (isotope of iodine). Radiation therapy can also be used to kill cancer cells.

Explain what the different energy levels for electrons are.

The atomic energy levels are K, L, M, N and so forth. These are drawn as rings to indicate an electron’s energy. The first energy level can only have 2 valence electrons while the succeeding levels can have up to 8 valence electrons per shell.  When an atom absorbs energy, electrons move to a higher energy level, farther from the nucleus. When an electron falls to a lower energy level, energy is released.

What are ions and how are they formed?

Ions are positively charged atoms. Ions are formed when electrons transfer between atoms (Ex: NaCl).

What is a chemical bond?

A chemical bond is the force of attraction between atoms and ions.

What are compounds?

Compounds are the result of two or more chemical DIFFERENT elements bonding together.

What is an ionic bond?

Ionic compounds are held together due to the two oppositely charged ions being attracted to one another. Ex-1) NaCl -> Na has one electron in its third orbital and tends to be an electron donor (trying to reach octet and it closer to give away) + Cl (with seven electrons in its third orbital, it tends to be an electron acceptor (trying to reach octet and it is closer to add one and take). Na is now positive and Cl is now negative.

What is a covalent bond?

Covalent (Polar - unequal electron share + Non-polar - equal electron share)-> Covalent bonds are the result of atoms sharing electrons in a manner where each atom has an octet of electrons in the outer orbital (or a duo of electrons for H and He). Ex-2) H-H — this fulfills the octet for hydrogen as it only needs two valence electrons to fulfill its octet. Now, each atoms has two (through sharing).

What is a hydrogen bond?

Hydrogen -> Attraction between a partially (-) atom in one molecule and a partially (+) hydrogen in another molecule. The attraction between a partially negative (-) oxygen in one molecule and a partially positive (+) hydrogen in another molecule results in a hydrogen bond. These bonds are weak individually but strong collectively. These bonds happen between water molecules.

What is the difference between hydrophobic and hydrophilic molecules?

Hydrophobic molecules - dislike water and will aggregate, clump, and shrink, minimizing the molecules disruption of water’s hydrogen bonding.

Hydrophilic molecules - love water and are polar molecules that readily form hydrogen bonds with water, disrupting the water’s hydrogen bonding.

What is oxidation?

Loss of an electron.

What is reduction?

Gain of en electron.

What are valence electrons?

The # of electrons found in the outermost energy level of atom.

List all 7 special properties of water.

Water has a high heat capacity, high heat of vaporization, is a great solvent, has cohesive and adhesive properties, has high surface tension, and ice is less dense (mass packed in space is lighter than ice) than liquid water - causes ice to float to the top.

What are the concentrations of solutions?

The concentration of solutions is the ratio of solute to the given amount of solvent.

What are acids and bases?

While acids are substances that release hydrogen ions when dissociated in water, bases are substances that release hydroxide ions or take up hydrogen ions when dissociated in water.

What is the pH scale and how is it determined?

pH scale is the scale that measures the acidity of basicity (alkalinity) of a solution. The number of hydrogen ions in fluid determines its pH. pH scale ranges from 0 to 14.

What is the pH range of acids, bases, and neutral?

Acids-has pH less than 7

Bases-has pH greater than 7

Neutral pH =7

What is a buffer? How do Bicarbonate and Carbonic Acid fit into the buffer system?

A buffer is a chemical or combination of chemical that keep pH within normal limits. Bicarbonate and Carbonic acid work to the up excess ions to halt them from impact the pH.

Where are reactants and products relative to the yield arrow?

Reactants are on the left side while products are on the right hand side.

What three important factors control chemical reactions and why?

1.) Temperature - The higher the temperature, the faster a reaction can occur since the reactants can collide more often.

2.) Concentration of Reactants and products - The more reactants available allows frequent collisions, and more products slow the reaction and reversible reactions may speed the reaction in the reverse direction.

3.) Catalysts - substance that increase the rate of a reaction-shortening the time needed to reach equilibrium, and in living systems these catalysts are called enzymes.

Why does salt (NaCl) dissolve in water (H2O)? (Hint: hydrogen bonding, polarity, and electronegativity).

Although the ionic bonds holding the crystal together in NaCl are relatively strong, when salt is placed in water, the electrical attraction of the water molecules disrupts the forces holding the ions in their crystal matrix which causes the salt to dissolve into a roughly equal mixture of Na+ and Cl- ions. Overall, individual Na Cl ions break away from the salt lattice and become surrounded by polar water molecules whose partial charges are attracted to the charges of the ions. Surrounded by these hydration cells, the ions never re-enter the salt lattice.

What does the polarity of water look like?

Partial positive charges on the hydrogen (2) and a partial negative charge on the oxygen (1) due to the oxygen’s high electronegativity and pull for electrons.