1 Cells

Units Goals Analyze the nature of the relationships between structures and functions in living cells. Explain the role of cell organelles for both prokaryotic and eukaryotic cells. Including the cell membrane, in maintaining homeostasis and cell reproduction. Explain the impact of water on life processes. Osmosis and diffusion

All living things are made of small structures called cells. 2 What is a cell? All living things are made of small structures called cells.

HISTORY OF THE CELL

Robert Hooke 1665 One of the first people to see cells. 3 Robert Hooke 1665 English scientist One of the first people to see cells. Looked at Cork Cells. First to use the word cells- named them for the places that monks sleep in the monastery. cork

Concluded that all animals are made up of cells 5 1839 Theodor Schwann Concluded that all animals are made up of cells

Concluded that all Plants are made up of cells 6 1839 Matthias Schleiden Concluded that all Plants are made up of cells Clip

Cell Theory All living things are made up of cells 7 Cell Theory All living things are made up of cells Cells are the basic unit of structure and function in living things All cells come from pre-existing cells Clip

7 What is a cell made of? Cells are ~90% water.

Cell Composition 50% protein 60% H 15% carbohydrate 25% O 8 Cell Composition Of the dry weight: 50% protein 15% carbohydrate 15% nucleic acid 10% lipid 10% miscellaneous Approximate composition by element: 60% H 25% O 12% C 5% N

What are the two basic types of cells?

8 Prokaryotic & Eukaryotic

Prokaryotic Cells Are all singled celled organisms--ex: Bacteria 9 Prokaryotic Cells DO HAVE Cell membrane Ribosomes DNA DO NOT HAVE Organelles Nucleus Are all singled celled organisms--ex: Bacteria Thought of as more ancient life forms…they came first. They still carry out all of life’s functions!

Eukaryotic Cells Have organelles. 10 Eukaryotic Cells Have organelles. Believed to have evolved from prokaryotic cells (Theory of Endosymbiosis). Can be singled-celled or multi-cellular organisms. ex: plants, animals, fungi, protista

11 How big are cells?

Major Theme “Function dictates form” Humans have ~200 cell types All cells do not look alike Ex: Nerve cells long and spindly Cells that store fat are rounded &large Structural cells are square Animation

11 Size differences: Pro: .1-10 μm Eu: 10-100 μm Cells come in many different shapes & sizes.

How are cells organized? 12 How are cells organized?

The Cell Membrane (aka: plasma membrane) Basic Cell Structure The Cell Membrane (aka: plasma membrane) 13 The outside of all cells are surrounded by a membrane made of phospholipids. Nickname: “The gatekeeper”

14 about as fluid as salad oil Membranes are fluid Membrane molecules are held in place by relatively weak hydrophobic interactions. Most can drift laterally, but rarely flip-flop from one layer to the other.

Plant cell wall are made of Cellulose. 15 Plant and Fungi cells also have a cell wall outside of the cell membrane. Plant cell wall are made of Cellulose. Fungi cell walls are made of Chitin.

Cell walls can also be found in fungi and bacteria. 16 Cell walls can also be found in fungi and bacteria. The cell wall provides support and protection for these cells. In plants, the cell wall is made of the carbohydrate cellulose.

Inside of the cell The Cytoplasm 19 Inside of the cell The Cytoplasm The cytoplasm contains all of the organelles in eukaryotic cells.

The jelly-like insides of a cell is called cytoplasm. Cells are filled with organelles that each do something to keep the cell alive. The jelly-like insides of a cell is called cytoplasm. 20

Organelles in the Cytoplasm 21 Organelles in the Cytoplasm Each organelle has a specific function so that the cell can do its job. Each organelle has its own job! Remember: ONLY EUKARYOTIC CELLS HAVE ORGANELLES!!!!

What an organelle? Organelle means “tiny organ.” 22 What an organelle? Organelle means “tiny organ.” Organelles function together to help the cell carry out all of life’s activities!!

23 Organelles of the Cell

Nucleus-The Control Center 24 The “Brain” Contains the DNA DNA controls which proteins get made-and when! Where ribosomes are made

The nucleus has a phospholipid bilayer around it. The nuclear pores allow substances to move into and out of the nucleus. The DNA NEVER leaves the nucleus. 25

Ribosomes Not technically an organelles. Nickname: “protein maker” 27 Not technically an organelles. Nickname: “protein maker” Place where proteins are made. They help put the amino acids together to make proteins. Made of the nucleic Acid-RNA website

Endoplasmic Reticulum 29 Endoplasmic Reticulum Membrane system that’s function involves protein synthesis and transport. Can be thought of as a Highway and a place of protein synthesis.

Two types of ER Smooth Rough 30 No attached ribosomes

ER branches off from the nuclear membrane. 31 ER branches off from the nuclear membrane.

Golgi Apparatus Nickname: “UPS” 33 Golgi Apparatus p. 175 Nickname: “UPS” Packages molecules and sends them to their destination. Also checks to make sure the molecules are put together correctly, if not correct it sends them back to the ER. Website

Animation

35 Golgi w/vesicles Vesicles are packages of material that are being transported.