Biology Flash Cards Unit 1

Biology

The scientific study of life.

Cell

The smallest fundamental unit of structure and function in living organisms.

Stimulus

A change in the environment that causes an organism to react.

Homeostasis

Maintenance of a stable internal environment.

Metabolism

Cellular processes that use or release energy.

DNA/RNA

Nucleic acids that encode genetic instructions in living organisms.

Reproduction

The process by which cells and organisms produce new cells or offspring.

Growth and Development

The processes by which organisms increase in size and mature.

Science

A process for understanding the natural, material world.

Empirical

Observable, measurable, and experience-based evidence.

Scientific Method

A systematic approach that starts with a question and proposes hypotheses.

Hypothesis

A scientifically testable idea.

Null Hypothesis (H0)

States that there will be no change, difference, or that nothing will happen.

Alternative Hypothesis (Ha)

States that there will be a change, a difference, or that something will happen.

Direct Observation

Using our natural senses to gather information.

Indirect Observation

Using instruments like a microscope to gather information.

Biological Stains

Substances that make clear or translucent objects visible.

Experiment

A controlled, empirical procedure designed to test a hypothesis.

Variable

A feature of the experiment that can change.

Independent Variable

The variable that is being experimentally manipulated.

Dependent Variable

The feature that is being tested in an experiment.

Control Group

A group that does not receive treatment, serving as a baseline for comparison.

Statistics

The branch of mathematics that studies the gathering and analysis of data.

p Value

The probability of obtaining results based on random chance; if greater than 0.05, it favors the null hypothesis.

Chemistry

The scientific study of matter.

Atom

The basic unit of matter, composed of protons, neutrons, and electrons.

Electron

A negatively charged atomic particle.

Proton

A positively charged atomic particle.

Neutron

An atomic particle with no charge.

Chemical Bonds

Interactions that hold atoms together to form molecules.

Ionic Bond

A chemical bond that forms between ions of opposite charges.

Covalent Bond

A bond formed when two or more atoms share electrons.

Double Bond

A bond in which two atoms share two electrons.

Organic Molecule

Carbon-based molecules essential for life.

Organic Chemistry

The branch of chemistry dealing with organic molecules.

Hydrophilic

A substance that dissolves in water.

Hydrophobic

A substance that does not dissolve in water.

Carbohydrates

Organic molecules primarily functioning in energy storage.

Monosaccharides

Simple sugars that are single molecules composed of 5-6 carbons.

Cellular Respiration

The process by which cells convert food and oxygen into usable energy.

Glucose

A monosaccharide that stores energy and is used in cellular respiration.

Disaccharides

Two monosaccharides bonded together.

Sucrose

An example of a disaccharide.

Benedict’s Test

A test that indicates the presence of monosaccharides through color change.

Polysaccharides

Long chains of monosaccharides used for energy storage.

Starch

A polysaccharide that serves as an energy storage molecule in plants.

IKI Test

A test used to indicate the presence of starch.

Glycogen

A polysaccharide used for energy storage in animals.

Cellulose

A polysaccharide that forms the cell wall and is indigestible by most animals.

Lipids

Fats, oils, and waxes that are hydrophobic.

Triglycerides

A type of lipid consisting of a glycerol molecule and three fatty acid chains.

Glycerol

A component of triglycerides, bonded with three fatty acid chains.

Fatty Acid Chains

Long hydrocarbon chains that can be saturated or unsaturated.

Saturated Fat

Fatty acid chains with no double-bonded carbons.

Unsaturated Fat

Fatty acid chains with one or more double-bonded carbons.

Phospholipids

Modified triglycerides that form part of the cell membrane.

Steroids

Hydrophobic compounds characterized by four carbon rings.

Proteins

Macromolecules made of amino acids.

Amino Acids

The building blocks of proteins containing an amino and a carboxyl group.

Peptide Bonds

Bonds that form between the amino group of one amino acid and the carboxyl group of another.

Polypeptide Chain

A long chain of amino acids linked by peptide bonds.

Enzymes

Proteins that catalyze biochemical reactions.

Catalyst

A substance that speeds up a reaction without being consumed.

Substrate

The specific substance that an enzyme binds and acts upon.

Transport Proteins

Proteins embedded in membranes that facilitate the movement of substances.

Nucleic Acids

DNA and RNA that store genetic information.

Cellular Membrane

A phospholipid bilayer that surrounds the cell.

Phospholipid Bilayer

A double layer of phospholipids that makes up the cell membrane.

Passive Movement

Movement of substances that does not require energy.

Diffusion

The movement of ions and particles from an area of high concentration to low concentration.

Osmosis

The passive movement of water across a membrane.

Active Transport

Transport of substances that requires energy.

Cytoplasm

The jelly-like fluid where all organelles and cell components reside.

Cytoplasmic Contents

The materials and structures found within the cytoplasm, including organelles, ions, and proteins.

Prokaryotes

Cells that lack a nucleus, have DNA in the cytoplasm, and are typically very small (about 1 µm).

Cell Wall

A rigid outer layer made of peptidoglycan in prokaryotic cells, providing structure and protection.

Eukaryotes

Cells containing a nucleus that houses DNA and membrane-bound organelles.

Organelles

Membrane-bound compartments within eukaryotic cells, each with specific internal conditions and functions.

Nucleus

A double-membrane bound organelle that contains the cell's DNA and regulates gene expression.

Endoplasmic Reticulum (ER)

A series of membrane tubes connected to the nuclear envelope, with rough regions containing ribosomes and smooth regions involved in lipid synthesis.

Rough ER

Type of endoplasmic reticulum with attached ribosomes, involved in protein translation.

Smooth ER

Type of endoplasmic reticulum without ribosomes, involved in lipid synthesis and calcium ion storage.

Golgi Apparatus

A series of flat membrane-bound sacs that modify and route proteins and lipids received from the ER.

Mitochondria

Double-membrane bound organelles known as the powerhouse of the cell, where cellular respiration occurs.

Chloroplasts

Double-membrane bound organelles found in plant cells, responsible for photosynthesis.

Vacuole

A single membrane-bound structure in plant cells that can occupy up to 90% of the cell's volume, filled with cell sap.

Tissues

Groups of similar cells working together to perform specific functions.

Cell Specialization

Variations among cells in terms of nuclei count, organelles present, and specific functions.

Red Blood Cells

The most common cells in the human body, lacking nuclei and filled with hemoglobin for oxygen transport.

Skeletal Muscle Cells

Long, multinucleate cells with many mitochondria that contract to facilitate movement.

Fat Cells

Cells with one nucleus and large oil droplets, capable of increasing in size or number to store energy as fat.