Cells Study Guide

Cell Theory:

  1. All organisms are made of cells

  2. Basic unit of living things

  3. Come from other cells


more volume = bigger cells

more surface area = smaller cells


Ways cells get around surface area issues:

  1. Folded membrane

  2. Be smaller

  3. More nuclei


People to know:

Zacharius Jansen - Invented the compound microscope

Anton von Leewenhoek - Discovers unicellular organisms

Robert Hooke - Discovers cells

Theodore Schwann - Realizes all animals are mad of cells

Mattius Schleiden - Realizes all plants are made of cells

Rudolf Virchow - Proposes all cells come from other cells


Microscopes:

Light Microscope - Focuses light and allows us to see objects up to the size of bacterium

Electron Microscope - Focuses electrons and can magnify quite small

Scanning Electron Microscope - Used to see the surface of an object

Transmission Electron Microscope - Allows us to see most in depth to magnify


The two domains of life that are both prokaryotes are Archaea and Bacteria


Kingdoms of Life:

Animalia - Mullticellular, heterotrophic organisms that consume other organisms for food

Plantae - Primarily Multicellular, photosynthetic organisms that produce their own food w/ photosynthesis

Fungi - Heterotrophic organisms that obtain nutrients by absorbing dead matter

Protista - A diverse group of mostly unicellular eukaryotes that don’t fit neatly into other groups


Phospholipids make up most cell membranes. The term for this is phospholipid bilayer


Ex. Organelles in Prokaryotic Cells:

  • Cell Wall

  • Cell Membrane

  • Capsule

  • Nucleoid

  • Plasmid

  • Pilus

  • Flagellum


Cell Walls:

  • Function: Support, Shape, and Protect

  • Structure: Made up of carbohydrates

  • Properties: O2 and CO2 can pass through

  • Found in: Prokaryotes, plants, fungi, and some protists


Cell Membranes:

  • Primary Function: Regulates what enters/exits the cell

  • Secondary Function: Protection and Support


The tendency of particles to spread out, due to random molecular motions is called diffusion.

Osmosis is the diffusion of water across a selectively permeable membrane


Hypertonic Solution: The solution the cell sits in has a higher concentration of solutes

Hypotonic Solution: The solution the cells sits in has a lower concentration of solutes

Isotonic Solution: The solution the cell sits in has the same concentration of solutes


The two types of passive transport are diffusion and facilitated diffusion