Introduction to Biology and Fundamental Life Processes

Flashcards covering key vocabulary from the Introduction to Biology, including Scientific Method, Basic Chemistry, Molecules of Life, Cell Structure, Membrane Function, Metabolism, Cell Respiration, and Photosynthesis.

Biologist

A scientist who distinguishes living organisms from non-living things based on several distinct characteristics.

Genetic Material

The carrier of genetic instructions within an organism, essential for biological inheritance.

Producer

An organism that introduces energy into an ecosystem; interrelated with consumers and decomposers in the flow of energy.

Consumer

An organism that participates in the flow of energy by consuming producers or other organisms.

Decomposer

An organism that cycles materials through an ecosystem by breaking down organic matter.

Ultimate source of energy

The sun, which provides the primary energy for most life forms on earth.

Five-kingdom system

A classification system used to describe the primary kingdoms of living organisms.

Classification Categories

The hierarchical order of organisms from greater to fewer: kingdom, phylum, class, order, family, genus, species.

Scientific Method

A systematic method of investigating a problem through steps like observation, hypothesis, and experimentation.

Observation

The initial step of the scientific method involving the act of noting facts or occurrences.

Problem

A specific question or issue developed from preliminary observations in the scientific method.

Preliminary Information

The collection of data and existing knowledge gathered before formulating a hypothesis.

Hypothesis

A proposed explanation or tentative answer to a problem formulated during the scientific method.

Experiment

A designed test used to investigate a hypothesis and gather data.

Data

The information and measurements collected during an experiment.

Discussion

A step in the scientific method where experimental results are analyzed and interpreted.

Conclusion

The final step of the scientific method where results are summarized to support or refute the hypothesis.

Variable

The specific factor that is changed or tested within an experiment.

Theory

A well-substantiated explanation that is broader in scope than a hypothesis and supported by evidence.

Law

A descriptive statement or equation that reliably predicts events under certain conditions, distinguished from a theory.

Experimental Group

The group in a study that receives the variable being tested.

Control Group

The group in an experiment that does not receive the variable and serves as a baseline for comparison.

Matter

Anything that has mass and takes up space, contrasted with energy.

Energy

The capacity to do work or cause change, compared with matter.

Atom

The basic unit of a chemical element, consisting of protons, electrons, and neutrons.

Molecule

A group of atoms bonded together, representing the smallest fundamental unit of a chemical compound.

Atomic Number

The number of protons in the nucleus of an atom.

Atomic Mass

The mass of an atom, typically expressed in atomic mass units.

Proton

A subatomic particle with a positive charge found in the nucleus of atoms and ions.

Electron

A subatomic particle with a negative charge that can absorb or release energy.

Neutron

A subatomic particle with no charge found in the nucleus of atoms and ions.

Covalent Bond

A chemical bond involving the sharing of electron pairs between atoms.

Ionic Bond

A chemical bond formed through the electrostatic attraction between oppositely charged ions.

Hydrogen Bond

A weak chemical bond that plays a significant role in the properties of water and molecular structures.

Acid

A substance characterized by high hydrogen ion concentration and a low $pH$ value.

Base

A substance characterized by low hydrogen ion concentration and a high $pH$ value.

$pH$ Scale

A scale used to specify the acidity or basicity of an aqueous solution, important to living organisms.

Organic Molecule

A molecule that contains carbon atoms and is typically found in living organisms.

Hydroxyl (Alcohol)

A functional group consisting of an oxygen atom bonded to a hydrogen atom.

Carboxyl

A functional group containing a carbon double-bonded to an oxygen and single-bonded to a hydroxyl group.

Amino

A functional group consisting of a nitrogen atom bonded to two hydrogen atoms.

Phosphate

A functional group important in energy transfer, consisting of a phosphorus atom bonded to four oxygen atoms.

Methyl

A functional group consisting of one carbon atom bonded to three hydrogen atoms.

Monomer

A small organic molecule that can be bonded to other similar molecules to form a polymer.

Polymer

A large macromolecule composed of repeating structural units (monomers).

Dehydration Synthesis (Condensation)

The process of assembling monomers into polymers by removing a water molecule.

Hydrolysis

The chemical breakdown of a polymer into its basic subunits by the addition of water.

Carbohydrate

A molecule used for energy and structure, defined by its basic subunits such as monosaccharides.

Monosaccharide

The simplest form of carbohydrate and the basic molecular subunit of more complex sugars.

Disaccharide

A carbohydrate formed when two monosaccharides are joined by a glycosidic linkage.

Polysaccharide

A complex carbohydrate composed of long chains of monosaccharide units.

Lipid

A class of organic molecules that includes triglycerides, steroids, phospholipids, and waxes.

Triglyceride

A lipid molecule made of three fatty acids and one glycerol, acting as a primary energy source.

Saturated Fatty Acid

A fatty acid with no double bonds between carbon atoms, typically solid at room temperature.

Unsaturated Fatty Acid

A fatty acid with at least one double bond, typically liquid at room temperature.

Protein

A macromolecule composed of amino acid building blocks, essential for various cellular functions.

Amino Acid

The building block of proteins, containing a central carbon, amino group, carboxyl group, and an R group.

Peptide Bond

The covalent bond formed between two amino acids through dehydration synthesis.

Primary Structure

The unique sequence of amino acids in a polypeptide chain.

Secondary Structure

The localized folding or coiling of a protein chain, such as alpha helices or beta sheets.

Tertiary Structure

The overall three-dimensional shape of a single protein molecule.

Denaturation

The process in which a protein loses its specific shape and function due to factors like temperature or $pH$.

Nucleic Acid

A macromolecule, such as DNA or RNA, that plays a role in carrying genetic information.

Prokaryotic Cell

A cell that lacks a nucleus and membrane-bound organelles.

Eukaryotic Cell

A cell that contains a nucleus and membrane-bound organelles.

Chloroplast

The organelle where photosynthesis occurs, specializing in converting light to chemical energy.

Mitochondrion

The organelle responsible for aerobic respiration and producing $ATP$.

Fluid Mosaic Model

A model describing the plasma membrane as a flexible layer of lipid molecules and proteins.

Hydrophilic

The 'water-loving' part of the plasma membrane, typically referring to the polar heads of phospholipids.

Hydrophobic

The 'water-fearing' part of the plasma membrane, typically referring to the non-polar tails of phospholipids.

Diffusion

The movement of molecules from an area of high concentration to an area of low concentration.

Osmosis

The diffusion of water across a selectively permeable membrane.

Concentration Gradient

The process of particles moving through a solution from an area with a higher number of particles to an area with a lower number.

Facilitated Transport

Passive movement of molecules across a membrane via specific transmembrane integral proteins.

Active Transport

The movement of molecules across a cell membrane against their concentration gradient, requiring energy.

Exocytosis

The process by which cells move materials from within the cell into the extracellular fluid.

Endocytosis

A cellular process in which substances are brought into the cell.

Phagocytosis

A type of endocytosis where a cell engulfs large particles or whole cells (cell eating).

Pinocytosis

A type of endocytosis where a cell takes in liquid from the surrounding environment (cell drinking).

Hypotonic Solution

A solution with a lower solute concentration than the cell, causing the cell to take in water and swell.

Isotonic Solution

A solution with the same solute concentration as the cell, resulting in no net water movement.

Hypertonic Solution

A solution with a higher solute concentration than the cell, causing the cell to lose water and shrink.

First Law of Thermodynamics

The law stating that energy cannot be created or destroyed, only transformed.

Second Law of Thermodynamics

The law stating that energy transformations increase the entropy (disorder) of the universe.

Exergonic Reaction

A chemical reaction that releases free energy.

Endergonic Reaction

A chemical reaction that requires an input of energy to proceed.

Catalyst

A substance, like an enzyme, that increases the rate of a chemical reaction without being consumed.

Enzyme

A protein that acts as a biological catalyst to speed up metabolic reactions.

Substrate

The specific reactant molecule upon which an enzyme acts.

Product

The substance formed as a result of a chemical reaction between an enzyme and substrate.

$$ATP$$

The primary energy carrier in cells, formed and broken down to power metabolic processes.

Cell Respiration

The process of breaking down glucose and other energy sources to form $ATP$, occurring in aerobic or anaerobic pathways.

Anaerobic Pathway

A metabolic pathway for glucose that does not require oxygen.

Aerobic Pathway

A metabolic pathway for glucose that requires oxygen to produce energy.

Alcoholic Fermentation Pathway

An anaerobic process that converts pyruvate into ethanol and carbon dioxide.

Lactate Fermentation Pathway

An anaerobic process that converts pyruvate into lactic acid.

Photosynthesis

The process by which autotrophs use light energy, carbon dioxide, and water to produce glucose and oxygen.

Autotrophic

A mode of nutrition where organisms make their own food from inorganic substances.

Heterotrophic

A mode of nutrition where organisms obtain food by consuming other living things.

Light-dependent Reactions

The first stage of photosynthesis that requires light and involves photosystems $I$ and $II$ to produce oxygen.