Lecture 2 Cells

Nerve cells

form nervous tissue excitable, conduct electricity

Muscle cells

form muscle tissue excitable, contractile

Epithelial cells

line the body, protects the body from the outside

"Blast" cells

build connective tissue

Plasma (cell) membrane

controls entry into and out of cell

Cytoplasm

contains organelles

Nucleus

contains genetic info (chromatin) largest organelle 2 bilayers pores allow molecules to exit site of ribosome assembly (nucleolus)

Phospholipids

75% form barrier keeps insides in, outsides out

Cholesterol

20% helps keep ridged keeps from falling apart

Glycolipids

5% help ID cells and bind to neighbors

Peripheral proteins

only on one side of the membrane

Integral (transmembrane) proteins

goes all the way through the membrane transport channels

Glycoproteins

help ID cells and bind to neighbors

Cytosol

fluid and dissolved substances in cytoplasm

Organelles

functional part of cell

Non-Membrane Bound Organelles

ribosomes, cytoskeleton, centrioles

Membrane-Bound Organelles

endoplasmic reticulum, golgi apparatus, lysosomes, peroxisomes, mitochondria

Rough endoplasmic reticulum

directly connects to nuclear membrane studded w/ ribosomes make, fold, package proteins makes proteins that will leave the cell

Smooth endoplasmic reticulum

no ribosomes makes lipids (fatty acids, phospholipids, and steroids) detoxifies cells (alcohol, drugs, antibiotics) lots of SER found in liver cells, plasma cells, pancreas calcium storage (muscle)

Golgi apparatus

process products (proteins and lipids) for delivery some carbohydrate synthesis membrane stacks are not connected "package" passes through each membrane each membrane makes slight changes to package, then sends it away

Lyososome

round membrane-enclosed acid-filled 50 digestive enzymes "disinfects" worn out mitochondria, bacteria, virus, toxins, and waste from cell metabolism made by golgi

Mitochondria

powerhouse of the cell converts food molecules into CO2, H2O, and ATP huge consumers of O2 smooth outer and curled inner membrane have their own DNA, were likely absorbed in the past

Vesicles

small membrane sacs that specialize in moving products into, out of, and within a cell

Centrosome

microtubule organizing center

Centrioles

pair of barrel-shaped microtubular organelles at right angles to each other

Cilia

sweep materials across cell surfaces (brooms)

Flagella

moves cell itself (tail)