Exam 1 Study Guide Flashcards

Vocabulary flashcards based on the provided lecture notes.

Science

The process of using observations and experiments to draw conclusions based on evidence.

Observation

Noticing and describing events in a careful way.

Hypothesis

A testable explanation for an observation.

Experiment

Testing the hypothesis with controlled conditions.

Analyze Data

Look at results and use statistics to interpret them.

Conclusion

Determine whether results support the hypothesis.

Repeat

Share findings and allow for replication.

Peer-reviewed scientific literature

Literature that has been evaluated by other experts in the field before publication.

Hypothesis

A tentative, testable explanation for an observation.

Independent variable

What the scientist changes in an experiment.

Dependent variable

What is measured or observed as a result of changes in the independent variable.

Experiment

A controlled procedure to test a hypothesis by collecting data.

Control group

The group that does not receive the experimental treatment.

Experimental group

The group that receives the experimental treatment.

Statistical significance

Indicates that the results observed are unlikely due to chance (typically p < 0.05).

95% confidence interval

Means there’s a 95% chance the true value lies within the given range.

Confounding variables

Factors other than the independent variable that may affect the outcome.

Scientific theory

A well-substantiated explanation of natural phenomena, supported by a large body of evidence.

Scientific evidence

Data from controlled studies.

Anecdotal evidence

Personal stories, not systematically collected.

Epidemiology

The study of disease patterns and causes in populations.

Recall bias

Occurs when participants do not accurately remember past events, affecting study accuracy.

Correlation

Two variables occur together.

Causation

One variable causes the other.

Randomized clinical trial

Participants are randomly assigned to either a treatment or control group to reduce bias and test treatment effectiveness.

Biology

The study of life and living organisms.

Order (property of life)

Organized structure

Regulation (property of life)

Internal balance

Metabolism

The sum of all chemical reactions in an organism that maintain life.

Catabolic metabolism

Breaks down molecules to release energy.

Anabolic metabolism

Builds complex molecules using energy.

Chemistry

The study of matter and the changes it undergoes.

Matter

Anything that has mass and takes up space.

Mass

The amount of matter in an object.

Energy

The capacity to do work or cause change.

Element

A substance that cannot be broken down into other substances by chemical means.

Atom

The smallest unit of an element that retains the properties of that element.

Atomic number

Number of protons in an atom.

Atomic mass

Sum of protons and neutrons.

Molecule

Two or more atoms bonded together.

Molecular formula

Shows the number and type of atoms in a molecule (e.g., H₂O).

Macromolecule

A large molecule made of repeating subunits.

Monomer

The small unit that joins with others to form a polymer.

Carbohydrates

Organic molecules composed of carbon, hydrogen, and oxygen, typically used by the body as a quick source of energy.

Dehydration synthesis

Removes water to link monomers into polymers.

Hydrolysis

Adds water to break polymers into monomers.

Proteins

Provide structure, transport, communication, enzymes, and immune defense.

Protein denaturation

The protein loses its shape due to heat, pH, or chemicals, and it can no longer function.

Enzymes

Speed up chemical reactions by lowering activation energy.

Specificity (enzymes)

Each enzyme only acts on one type of substrate.

Substrate

The molecule the enzyme acts on.

Product (enzymes)

The result of the enzyme-catalyzed reaction.

Cofactor

Non-protein helper (like a metal ion).

Coenzyme

Organic helper (like vitamins).

Lipids

Store energy, make up membranes, and act as hormones.

Triglyceride

Glycerol + 3 fatty acids

Phospholipid

Glycerol + 2 fatty acids + phosphate group

Sterol

Four fused carbon rings (e.g., cholesterol)

Saturated fatty acid tails

No double bonds; straight tails; solid at room temp

Unsaturated fatty acid tails

One or more double bonds; bent tails; liquid at room temp

Nucleic acids

Store and transmit genetic information (DNA, RNA).

Cell

The basic unit of life that performs all necessary functions of living things.

Unicellular organisms

One cell performs all life functions.

Multicellular organisms

Specialized cells work together.

Plasma membrane (cell structure)

Outer boundary of the cell

Cytoplasm

Jelly-like fluid inside the cell.

DNA

Genetic material of the cell.

Ribosomes

Make proteins

Cohesion (of water)

Water sticks to itself.

Adhesion (of water)

Water sticks to other things.

Solvent

The substance doing the dissolving (e.g., water).

Solute

The substance being dissolved (e.g., salt).

Solution

A mixture of solute evenly dissolved in solvent.

pH

Measures the concentration of hydrogen ions (H⁺) in a solution.

Acid

Releases H⁺ in solution

Base

Accepts H⁺ or releases OH⁻.

Salt

Forms from the reaction of an acid and a base.

Buffer

Maintains stable pH by neutralizing acids/bases

Cell theory principle 1

All living things are made of cells

Cell theory principle 2

Cells are the basic unit of structure and function

Cell theory principle 3

All cells come from preexisting cells

Passive transport

Movement of molecules across a membrane without using energy.

Simple diffusion

Occurs across the membrane with small, nonpolar molecules like oxygen and carbon dioxide.

Facilitated diffusion

Uses proteins to help large or charged molecules (like glucose or ions) move across membranes without energy.

Osmosis

The diffusion of water through a selectively permeable membrane.

Hypertonic

Water moves out; cell shrinks

Isotonic

Water moves equally; no change

Hypotonic

Water moves in; cell swells

Active transport

Moves substances against their concentration gradient using energy (ATP).

Primary active transport

Uses ATP directly to move ions like sodium (Na⁺) and potassium (K⁺) through protein pumps.

Endocytosis

The cell engulfs material by wrapping it in membrane and bringing it inside as a vesicle.

Exocytosis

Vesicles fuse with the membrane to release materials out of the cell.

Smooth ER function

Makes lipids and detoxifies.

Rough ER function

Makes and modifies proteins

Golgi apparatus function

Modifies, sorts, and ships proteins and lipids.

Vesicles

Small membrane sacs used to transport materials in the cell.

Lysosomes function

Contain enzymes that digest and recycle worn-out cell parts or invaders.

Mitochondria function

Produce ATP through aerobic respiration. They are the “powerhouse” of the cell.

Cytoskeleton

A network of protein fibers that give the cell shape, support, and movement.

Microfilaments function

Cell movement and shape