Book 3 Unit 1

Cells

The smallest functional and structural unit of all living organisms

Cell Theory: Lists three basic characteristics of all cells and organisms
- All Organisms are made up of one or more cells
  - Unicellular Organisms: Made up of one cell
  - Multicellular Organisms: Made up of many cells
    - Cells often have specialized functions
- The cell is the basic unit of all organisms
- All cells come from existing cells
- Creators of the Cell Theory
  - Matthias Schleiden - Theory 1
  - Theodor Schwann - Theory 1, Theory 2
  - Rudolf Virchow - Theory 3
  - Anton van Leeuwenhoek - Theory 1
What cells have in common
- Cell Membrane: A protective layer that covers a cell's surface
- Cytoplasm: The region enclosed by the cell membrane that includes fluid and other organelles
- Organelles: A small body in a cell's cytoplasm that is specialized to perform a specific function
- DNA: Deoxyribonucleic Acid
  - In some cells, DNA is contained in the nucleus
Two Types of Cells
- Prokaryote: A single-celled organism that doesn't have a nucleus or membrane-bound organelles
  - DNA is located in the cytoplasm
- Eukaryotic: An organism made up of cells that contain their DNA in a nucleus
  - Most are multi-cellular

Basic particles

A group of atoms that are held together by a chemical bond

Import Molecules in cells
- Lipid: A fat molecule
- Proteins: A molecule made of smaller molecules known as amino acids
- Carbohydrates: Sugars, starches, and fiber
- Nucleic Acids: A molecule that carries information in cells
Phospholipid: A lipid that contains phosphorous
Form the cell membrane and allow water to pass through
Osmosis: The process in which water moves through the cell membrane

Mitochondria: A place where cellular respiration occurs
Ribosomes: The organelle that makes proteins by putting together chains of amino acids using instructions coded in the cell's DNA
Endoplasmic Reticulum: A system of membranes near the nucleus
- Assists in production, processing, and transport of proteins
Golgi Complex: The membrane-bound organelle that packages and distributes materials

Cell wall: A rigid structure that surrounds the cell membrane
Large Central Vacuole: A fluid-filled vesicle found in cells of most animals, plants, and fungi
Chloroplasts: Organelles in which photosynthesis occur

Lysosomes: Organelles that contain digestive enzymes, which break down worn-out or damaged organelles, waste material, and foreign invaders

Cells
- Multicellular
- Unicellular
Tissues: A group of similar cells that perform a common function
Organs: A structure made up of a collection of tissues that carry out a specialized function
Organ System: A group of organs that work together to perform body functions

Function: What the structure of a cell, tissue, or an organ determines
- Structure determines function

Unicellular
- Must perform all functions
  - Get nutrients
  - Exchange gases
  - Removing wastes
Multicellular
- Have different cell types to perform functions
- Delivering Nutrients
  - Break food mechanically and chemically
- Delivering Oxygen
  - A function of the respiratory system
- Removing Wastes

The maintenance of a constant internal state in a changing environment

Exchanging Materials
- Passive Transport
  - Diffusion: The movement of molecules from high concentrations to low levels
  - Osmosis: The diffusion of water through a semi-permeable membrane
- Active Transport: The movement of particles against a concentration gradient and requires the cell to use energy
Endocytosis: The process by which a cell uses energy to surround/enclose a particle in a vesicle to bring the particle into a the cell
Exocytosis: The process when particles are enclosed in a vesicle and released from a cell

Photosynthesis: The process when plants use energy from sunlight, carbon dioxide, and water to make sugar
6CO2 + 6H2O + Light Energy -> C6H12O6 + 6CO2

ATP: Adenosine Triphosphate
- Powers many chemical reactions that enables the cell to survive
Cellular Respiration: The process of breaking down food to produce ATP
C6H12O6 + 6CO2 -> 6C2 + 6H2O + Chemical Energy (ATP)