Cell Biology cells the basic unit of all

Cell Biology cells: the basic unit of all life on earth.

Characteristics of Life Nutrition Metabolism Growth Response Excretion Homeostasis Reproduction

Text Stem Cells do the homework!

Prokaryotes 3. 8 Billion years old No nucleus Exist everywhere Diverse Archaea and Eubacteria

cocci bacilli spirillum

Plague

One of the most devastating pandemics was the Black Death (1346 to 1361), which is believed to have been another outbreak of bubonic plague caused by the bacterium Yersinia pestis. This bacterium is carried by fleas living on black rats. The Black Death reduced the world’s population from an estimated 450 million to about 350 to 375 million.

Bacteria are also our friends Help us make cheese mmmmm cheese yogurt mmmmm yogurt bioremediation mmmmm bioremediaton

Prokaryotic Reproduction Binary Fission

Eukaryotes are much more modern they introduce the concept of compartmentalization

Let’s start with the Endomembrane System

Endomembrane System Nuclear envelope endoplasmic reticulum Glogi apparatus Lysosomes Vesicles Vacuoles Plasma membrane

Nuclear Envelope DOUBLE MEMBRANE! omg phospholipid surrounding nucleus

Just look at that double membrane

Endoplasmic Reticulum

Smooth E. R. —-no ribosomes attached Enzymes inside are involved in phospholipid synthesis Steroid synthesis (including the ole sex hormones) Detoxification of “the drugs” Barbiturates & Alcohol Storage of Ca 2+ during muscle contraction Carbohydrate metabolism

Rough E. R. -Yes, Ribosomes! Proteins meant for secretion Threaded into LUMEN (new word) Manufactures membrane

Golgi Apparatus Shipping and receiving stack of flattened sacs vesicles that bud from ER join to cis face of Golgi vesicles add their membrane and their contents to Golgi

More Golgi Flattened stacks are called Cisternae Glycoproteins have glyco part modified Manufactures some carbs—pectin in plants

Still more Golgi! Golgi products are sorted into VESICLES Current model is that these vesicles have surface molecules that act as markers to direct them to the plasma membrane or other organelles ya

Lysosomes lyse—to break apart -some—body Digestive compartments Hydrolytic enzymes acidic p. H Some white blood cells have lysosomes.

Vacuoles Diverse maintenance compartments Food vacuoles form from endocytosis (new word) Contractile vacuoles squeeze excess water out of freshwater unicellular eukaryotes In plants they store water—-CENTRAL VACUOLE Plants can have vacuoles with nasty chemicals to protect from predators

A final word about the Endomembrane system As membranes move from ER to Golgi and then on to other organelles, their composition, functions, and contents are modified