( Chapter 4 - Structure & Function ) 09.16+18+23

Micrographia

A work by Robert Hooke published in 1665, where he observed small cork slices and introduced the term 'cell'.

Cell Theory

A fundamental theory stating that all organisms are made of cells and that cells are the basic unit of life.

Virchow's Tenet

The principle that cells come from preexisting cells, established by Rudolf Virchow in 1855.

LUCA (Last Universal Common Ancestor)

The most recent common ancestor of all current life on Earth, believed to be a single-celled organism.

Functions of a Cell

Three primary functions: make supportive molecules, transform energy, and replicate when necessary.

Prokaryotic Cells

Cells that lack membranous organelles, are smaller and simpler than eukaryotic cells, and reproduce via binary fission.

Eukaryotic Cells

Complex cells that contain a nucleus and membranous organelles, with linear DNA and undergo mitosis and meiosis.

Plasma Membrane

A phospholipid bilayer that forms the outer boundary of a cell, regulating the entry and exit of substances.

Nucleus

The double-membraned organelle that houses and protects the cell's DNA, regulating cell activities.

Ribosomes

Complexes of ribosomal RNA and proteins that function in protein synthesis, found free-floating or on the rough ER.

Endomembrane System

A cellular system comprising membranes and organelles that work together to synthesize and transport proteins and lipids.

Rough Endoplasmic Reticulum (RER)

A type of ER studded with ribosomes, crucial for synthesizing proteins destined for secretion or lysosomes.

Smooth Endoplasmic Reticulum (SER)

Type of ER without ribosomes, involved in lipid metabolism and detoxification processes.

Golgi Apparatus

An organelle that processes, modifies, and packages proteins and lipids for transport to their destinations.

Lysosomes

Vesicles containing hydrolytic enzymes that digest waste materials and cellular debris.

Phagocytosis

The cellular process of engulfing large particles, bacteria, or dead cell debris through lysosomes.

Apoptosis

Programmed cell death, allowing cells to dismantle controlled cellular components, facilitated by lysosomes.

Cytoskeleton

A network of structural elements within a cell, providing support, structure, and facilitating cell movement.

Microtubules

Small tubes composed of tubulin that maintain cell structure and aid in cell motility and organelle movement.

Microfilaments

Long filaments made of actin that support cell shape, allow muscle contraction, and enable cell migration.