Untitled Flashcards Set

Energy

The ability of a living organism to perform work or cause change.

Kinetic energy

The energy an object possesses due to its motion.

Potential energy

An object's stored energy due to its relative position or internal structure.

Entropy

The measure of a system's thermal energy per unit temperature that is unavailable for doing useful work; it is also a measure of disorder or randomness within a system.

Energy coupling

Occurs when the energy produced by one reaction or system is used to drive another reaction or system.

Adenosine Triphosphate (ATP)

The molecule that stores energy for cellular processes.

ADP (Adenosine Diphosphate)

The product formed when ATP loses a phosphate group.

Substrate

The molecule that the enzyme binds to and alters during a chemical reaction.

Active site

A region on an enzyme that binds to a protein or other substance during a reaction.

Enzyme

Proteins that help speed up chemical reactions in our bodies.

Activation energy

The minimum amount of energy required for a chemical reaction to occur.

Diffusion

The process in which a substance moves through a semipermeable membrane or in a solution without any help from transport proteins.

Concentration gradient

The difference in the concentration of a substance between two areas.

Passive transport

Transport that does not require energy, moving down the concentration gradient.

Active transport

Transport that requires energy, moving against the concentration gradient.

Facilitated diffusion

The diffusion of solutes through transport proteins in the plasma membrane, a type of passive transport.

Osmosis

The process by which water or other solvents move through a semipermeable membrane from a region of high concentration to a region of low concentration.

Solution

A homogeneous mixture made up of a solute dissolved within a solvent.

Solute

The substance that dissolves in another substance.

Solvent

A substance (molecule) with the ability to dissolve other substances.

Isotonic

Having the same concentration of solutes across a semipermeable membrane.

Hypotonic

Having a lower concentration of solute than another solution (e.g., more water than salt).

Hypertonic

Having a higher concentration of solute than another solution (e.g., more salt than water).

Exocytosis

The process of moving large molecules and waste OUT of a cell; it is a type of active transport.

Endocytosis

The process by which cells bring materials from outside the cell into the cell.

Phagocytosis

The process by which cells engulf and digest foreign substances, dead cells, or other debris.

Receptor-mediated endocytosis (RME)

A process that moves molecules into a cell by binding them to cell surface receptors.

Cytoskeleton

a network of protein filaments that gives a cell its shape and structure

Microtubules

Hollow tubes that help maintain cell structure, major components of the cytoskeleton, intracellular transport

Intermediate filaments

Protein strands that provide structure and stability to cells. Form an elaborate network in the cytoplasm of most cells, extending from a ring surrounding the nucleus to the plasma membrane

Microfilaments

protein filaments in the cytoplasm of eukaryotic cells that form part of the cytoskeleton, provides support and transport

Cilia

Many tiny hair-like structures that help move cells and substances.

Flagella

Antenna-like structures that help move cells through liquids.

Nucleus

The repository of genetic information and the cell's control center; involved in DNA replication, transcription, and RNA processing.

Ribosomes

Molecules that turn mRNA into proteins.

Rough Endoplasmic Reticulum (Rough ER)

Studded with ribosomes, synthesizes proteins destined to be secreted from the cell or incorporated into the cell membrane, conducts quality checks.

Smooth Endoplasmic Reticulum (SER)

Responsible for the synthesis of essential lipids such as phospholipids and cholesterol.

Golgi apparatus

Processes and packages proteins and lipids and sends them where they need to go.

Lysozymes

Natural defense mechanisms against bacteria by breaking down the peptidoglycan layer in bacterial cell walls.

Vacuoles

Major roles include storing nutrients and water.

Mitochondria

Organelles that generate energy for the cell by converting food into adenosine triphosphate (ATP).

Chloroplasts

Organelles that produce energy through photosynthesis and oxygen-release processes.

Endosymbiotic theory

Explains that mitochondria and chloroplasts originated from free-living prokaryotic cells engulfed by early eukaryotic cells.

Extracellular matrix (ECM)

Composed of collagen, proteoglycans, and glycoproteins; helps cells attach to and communicate with nearby cells.

Cell wall

Provides structural support, shape, protection, and functions as a selective barrier.