Download the cell lab2 part 1 and 2

Human Biology
Practical part
Technical college of health
Human biology
First year
Part 1
The cll
Lab.2
cell
A cell is the smallest unit that is capable of
performing life functions.
Discovery of Cells:
_ Robert Hooke (mid-1600s)
– Observed sliver of cork
– Saw “row of empty boxes”
– Coined the term cell
Cell Theory
• (1839)Theodor Schwann & Matthias
Schleiden
“ all living things are made of cells”
• (50 yrs. later) Rudolf Virchow
“all cells come from cells”
Cell Size:
Plasma Membrane
Plasma Membrane: consist of double layer of phospholipids and
proteins
Membrane Proteins:
1. Channels or transporters
– Move molecules in one direction
2. Receptors
– Recognize certain chemicals
3. Glycoproteins
– Identify cell type
4. Enzymes
– Catalyze production of substances
Cell Walls:
• Found in plants, fungi, & many protists
• Surrounds plasma membrane
Lab experiment and activity
1- Preparing direct and indirect stained slides for different type
of cell including human skin, mouth swab, and plant cell
2. Examining the checking egg under microscope
3. Drawing the both animal and plant cell in the lab
Human Biology
Practical part
Part 2
Movement Across the
Plasma Membrane:
Lab.2
Movement Across the Plasma Membrane:
-A few molecules move freely: Water, Carbon dioxide,
Ammonia, Oxygen
– Carrier proteins transport some molecules
– Proteins embedded in lipid bilayer
– Fluid mosaic model – describes fluid nature of a
lipid bilayer with proteins
Diffusion
Diffusion through Cell Boundaries
• Particles move from an area of high concentration to an area of
lower concentration
• No energy is required
Osmosis
• Diffusion of water through a
selectively permeable
membrane
Isotonic
"ISO" means the same
Concentration of solutes (salts)
is the same inside and outside
of cell.
• Water flows in and out in equal
amounts
• No effect on cell
Hypertonic
“Hyper” means more Concentration of solutes is more outside the cell than
inside
• Water flows out of cell
• The cell shrivels and may die.
• This is why it is dangerous to drink sea water
• This is also why "salting fields" was a common tactic during war, it would kill
the crops in the field, thus causing food shortages.
Hypotonic
"HYPO" means less Concentration of solutes is less outside the cell than in
• Water flows in
• The cell swell with water and becomes “turgid”
Active Transport
• Carried molecules by protein pumps found in the membrane
• Energy is required
Lab experiment and activity
1- Preparing normal saline, hypertonic and hypotonic solution.
2. Demonstrating the cell in the hypertonic and hypotonic
solution.
3. Drawing plasma membrane of the cell in the lab.
Any questions