What is Life?

A “little” history… theory

7 MUST HAVE Characteristics of Living Things: 1. It obtains and uses energy 2. It grows and develops 3. It reproduces 4. It responds to the environment including movement 5. It breathes/respires (exchange of gasses) 6. It produces waste 7. It is made up of cells

Is it made up of cells? Cells Eukaryotes (has a nucleus) Unicellular Ex. Protists Multicellular Ex. Plants and Animals Prokaryotes (No Nucleus) Ex. bacteria

A View of the Cell Cell Features

Discovering the Cell Robert Hooke – used a microscope to study cork; coined the term “cell” b/c they looked like cells in a monastery where monks lived! Anton van Leeuwenhoek – first person to record looking at water under a microscope

Matthias Schleiden – Observed that plants are composed of cells Theodor Schwann – Observed that animals are composed of cells Rudolph Virchow – Determined that cells come from other cells; cells are not spontaneously generated.

I. Introduction to the Cell Cell Theory – All living organisms are made up of one or more cells. – Cells are the basic unit of structure & function in organisms. – All cells come from preexisting cells.

Cells are the building blocks of you. Cells form tissue Tissue forms organs Organs form systems Systems form organisms

Reflection: Why is this important? It helps us to understand how we are made and how we are similar.

Success is: Listening and taking good notes Coloring the cells correctly

Cell Shape—they can all be different! The shape of a cell depends on its function.

– Most cells contain a variety of membrane- bound ORGANELLES - cell parts that PERFORM SPECIFIC FUNCTIONS FOR THE CELL Internal Organization

– A Large Organelle near the Center of the Cell is the NUCLEUS. IT CONTAINS THE CELL'S GENETIC INFORMATION (DNA) AND CONTROLS THE ACTIVITIES OF THE CELL. – The nucleus is covered by the NUCLEAR MEMBRANE which controls what comes in and out of the nucleus “BRAIN” of the cell

DNA – Genetic material that contains information to make new cells and organisms – “Blueprint” of the cell – Chromosomes hold the DNA

Other Organelles MITOCHONDRIA – this bean-shaped structure is the cell’s energy center. It turns sugars into chemical energy. “Powerhouse” of the cell

Other Organelles GOLGI APPARATUS – processes, packages and secretes proteins Comparable to a Factory or Post Office in the real world

Other Organelles LYSOSOMES – Break down larger food molecules into smaller molecules - Digest old cell parts - Rid the cell of waste materials and protect from “foreign invaders”

Other Organelles ENDOPLASMIC RETICULUM– Transportation system to distribute proteins to other parts of the cell. “intracellular highway" RIBOSOMES – Make proteins! Positioned along the rough ER

Other Organelles CYTOPLASM – jelly-like substance that support/protects the organelles VACUOLE – storage area for water and other substances, plant cells usually have one large central vacuole (animal cells have 2-3 small vacuoles)

Protein Production The cell is like a factory. It’s end product is protein which goes to the body to serve different functions. The nucleus contains the DNA. 1. DNA has the instructions to build the protein 2. These instructions are sent to the ribosomes on the Rough ER 3.The ribosomes build the protein from amino acids and send it through the smooth endoplasmic reticulum via transport vesicles to the golgi apparatus. 4.The proteins are delivered to the golgi apparatus where they are completed and “tagged” for export outside the cell

Protein Pathway Nucleus Ribosomes (DNA) (On Rough ER) Build the proteins Golgi apparatus Smooth ER Other organelles inside and outside the cell

CELL MEMBRANE Selectively permeable (semi-permeable) ; it regulates what comes into the cell and what leaves the cell Provides support and protection Similar to our skin

Have additional structures CELL WALL – surrounds the membrane and provides additional support CHLOROPLASTS – contain green pigment called Chlorophyll, used in photosynthesis CENTRAL VACUOLE – large water container in the center of the cell Plant Cells