Cell Structure and Function

These flashcards cover the vocabulary related to cell structure and function, including definitions and key concepts from the lecture notes.

Cell

The basic structural and functional unit of every organism.

Prokaryotes

Cells that lack a nucleus, found in domains Bacteria and Archaea.

Eukaryotes

Cells that contain a nucleus and membrane-bound organelles.

Organelle

Membrane-bound structures in eukaryotic cells that perform specific functions.

Endomembrane system

A system of organelles that work together to modify, package, and transport lipids and proteins.

Plasma membrane

The boundary that separates the cell from its external environment, made of a phospholipid bilayer.

Nucleus

The organelle that houses chromosomes and is surrounded by the nuclear envelope.

Ribosome

A complex of RNA and proteins that synthesizes proteins.

Endoplasmic Reticulum

A network of membranous sacs and tubes involved in protein and lipid synthesis.

Rough ER

The region of the endoplasmic reticulum studded with ribosomes, involved in protein synthesis.

Smooth ER

The region of the endoplasmic reticulum that synthesizes lipids and detoxifies certain chemicals.

Golgi Complex

An organelle that modifies, sorts, and packages proteins and lipids for secretion or delivery.

Lysosome

A membrane-bound sac containing hydrolytic enzymes for digestion of macromolecules.

Vacuole

A large vesicle that stores substances and helps maintain turgor pressure in plant cells.

Mitochondria

Organelles known as the powerhouse of the cell, that generate ATP through cellular respiration.

Chloroplast

Organelles found in photosynthetic organisms that carry out photosynthesis.

Endosymbiont Theory

A theory that explains the origin of mitochondria and chloroplasts as engulfed prokaryotic cells.

Cytoskeleton

A network of fibers that provides structural support and facilitates movement within the cell.

Microtubules

Hollow rod-like structures that assist in the movement of organelles and chromosomes.

Microfilaments

Thin solid rods made of actin that help maintain cell shape and enable motility.

Intermediate Filaments

Fibrous proteins that maintain cell shape and anchor organelles.

Transport Vesicle

Membrane-bound sac that carries materials between organelles.

RNA Polymerase

An enzyme that synthesizes mRNA from a DNA template during transcription.

mRNA (messenger RNA)

A type of RNA that carries the genetic information from DNA to the ribosome.

Transcription

The process of synthesizing RNA from a DNA template.

Translation

The process of synthesizing proteins using mRNA as a template.

Hydrolysis

The chemical breakdown of a compound due to reaction with water, often catalyzed by enzymes.

Autophagy

The process by which a cell recycles its own organelles and macromolecules.

Osmotic pressure

The pressure required to prevent the flow of water across a semipermeable membrane.

Turgor pressure

The pressure of the cell contents against the cell wall in plant cells.

Cristae

The inner membrane folds of mitochondria that increase surface area for ATP production.

Thylakoids

Membranous sacs in chloroplasts where the light-dependent reactions of photosynthesis occur.

Stroma

The fluid-filled space surrounding thylakoids in chloroplasts, site of the Calvin cycle.

Cell wall

A rigid layer surrounding the cell membrane in plant cells, maintaining structure and support.