Human Anatomy (205)

[Histology] [Organelles] [Cytology practice tests]

Cytology

Check out theVirtual Cell Webpage
Compounds of Cells
- Proteins, Lipids, Carbohydrates, and Nucleic Acids
- Water, solutes, pH & buffers
- Electrolytes
The Cell Membrane structure is a fluid mosaic model [phopholipids and proteins]
Phospholipids form bilayer sheet Function of plasma membrane proteins
as transport channels and receptors.
Movement Through Cell Membranes
- Diffusion [particles move through membrane from high concentration to low]
- Facillitated diffusion [particle through protein channel]
- Osmosis is passive transport of water. See more osmosis
- Filtration is movement of molecules by hydrostatic pressure
- Active Transport pumps solutes against diffusion gradients
- Endocytosis is a process in which membrane engulfs particles & large molecules
Cell Nucleus - see illustration
- Special double nuclear membrane on surface [nuclear envelope]
  - outermost membrane continuous with rough E.R.
  - nuclear pores form where inner and outer membrane touch
- DNA organized with proteins into chromatin
- Nucleolus is cluster of chromatin with genes that encodes for rRNA
- See Lab Interactive cell model
Cytoplasmic Organelles
- ER is made of membrane channels used to transport substances within the cell
  - Rough ER has ribosomes attached to the membranes
  - Smooth E.R. lacks ribosomes
- Ribosomes assemble amino acids into protein
- Golgi is involved in cellular secretion
- Mitochondrion has reactions that form ATP
- Lysosomes and Peroxisomes
- See Lab Interactive cell model
Cytoskeleton is a cytoplasmic network of protein filaments that supports and gives shape to the cell.
Three types of protein fibers make up cytoskeleton.
1. microtubules
  - are made of protein, tubulin molecules
  - also make up spindle that moves chormosomes during mitosis.
  - also function in movement of Cilia and flagella
  - also are found in centrioles
2. Intermediate filaments
3. microfilaments
The centrosome contains a pair of centrioles and each contains 9 microtubule triplets.
Cilia and Flagella contain a ring of 9 microtubule doublets + 2 central single microtubles.
Cell Cycle and Mitosis produces genetically identical cells
- photographs of Whitefish blastula mitosis,
- see mitosis animation
Meiosis reduces double set of chromosomes (diploid) in cell to single set

Crosssords, quizzes and cytology games

Crossword on cell organelles
Play Quia [ cell] [cell organelles] [mitosis]
Identify parts of the anatomy lab microscope
Identify organelles on Lab Interactive cell model or try cell structure & function Quiz

Dynamic Human
at McGraw-Hill

Human Anatomy
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Phospholipids form bilayer sheet	Function of plasma membrane proteins as transport channels and receptors.