BTE101 L2 Cell Biology Review

Flashcards covering the principles of cell theory, organelle functions, differences between prokaryotic and eukaryotic cells, and plasma membrane structure based on lecture notes.

Theodor Schwann & Matthias Schleiden (1839)

The scientists credited with the cell theory principle that "all living things are made of cells."

Rudolf Virchow

The scientist who, 50 years after Schwann and Schleiden, stated that "all cells come from cells."

Principles of Cell Theory

1. All living things are made of cells. 2. The smallest living unit of structure and function of all organisms is the cell. 3. All cells arise from pre-existing cells (discarding spontaneous generation).

Cytosol

The liquid component of the cytoplasm that surrounds intracellular organelles.

Cytoplasm

All contents of a cell except the nucleus, including all organelles as well as the cytosol.

Common Features of All Cells

DNA (genetic material), Plasma membrane (phospholipid bilayer), Cytoplasm (including cytosol and organelles), and Ribosomes.

Prokaryotic Cell Size

Generally small, ranging from $1-10\,\mu m$.

Eukaryotic Cell Size

Generally large, ranging from $5-100\,\mu m$.

Prokaryotic Genome

DNA with nonhistone protein; the genome is located in a nucleoid and not surrounded by a membrane.

Eukaryotic Genome

DNA complexed with histone and nonhistone proteins in chromosomes; contained within a nucleus with a membranous envelope.

Nucleolus

A condensed region within the nucleus where ribosome synthesis occurs.

Rough Endoplasmic Reticulum

Part of the endoplasmic reticulum associated with ribosomes; it makes secretory and membrane proteins.

Smooth Endoplasmic Reticulum

Part of the endoplasmic reticulum that makes lipids.

Golgi apparatus

The cellular organelle responsible for modifying proteins.

Mitochondria

The organelles that produce energy for the cell.

Lysosome

An organelle found in animal cells that digests food and waste materials.

Plasmodesmata

Channels that connect two plant cells.

Central Vacuole

A plant cell organelle filled with cell sap that maintains pressure against the cell wall.

Chloroplast

The site of photosynthesis in plant cells and some algae.

Integral membrane proteins

Proteins that are permanently embedded within the plasma membrane, including transmembrane proteins and integral monotopic proteins.

Transmembrane proteins

Integral membrane proteins that span the entire plasma membrane.

Peripheral membrane proteins

Proteins only temporarily associated with the membrane; often involved in cell signalling and can be easily removed.

Cell Type Diversity

The range of different cell types that comprise a tissue or organ, arising from differential gene expression.

Differential gene expression

The process where specific genes are activated in some cells but not others; for example, hemoglobin genes are activated in red blood cells but not brain or muscle cells.

Histone

A protein associated with DNA that provides structural support; DNA wraps around these complexes to help it fit into the nucleus in a compact shape.

Peptidoglycan

The material found in the cell walls of organisms in the Kingdom Eubacteria.

Chitin

The material found in the cell walls of organisms in the Kingdom Fungi.