Transcript 2.4.08 105K lecture

BIO105K tutoring
Thursdays 1:00 – 2:00
in the Fish Bowl = room 153 Science Building
Sam Giles
M
W
Day Date
1/14
1/16
Subject
To be read prior to this class period:
no class - Snow Day!
Evolution: Unity and Diversity
Chapter 1
M
W
1/21
1/23
no class – Rev. Martin Luther King, Jr. Day
Water and the Chemical Environment
Chapter 2 (except pp30-35)
M
1/28
Quiz #1 on Ch. 1 and parts of Ch. 2 and related lectures/handouts
(no make ups for missed quiz)
Cell Membranes
Chapter 6
W
M
1/30
2/4
Macromolecules
Macromolecules
W
2/6
Quiz #2 on Ch. 3 and 6 and related lectures/handouts
(no make ups for missed quiz)
The Cell
Chapter 7
M
W
M
W
M
2/11
2/13
2/18
2/20
2/25
Bioenergetics
Cell Respiration
no class - Winter Break
no class - Winter Break
EXAM I
Chapter 3 (except pp63-69)
Chapter 9
Chapters 1, 6,7, parts of 2, 3
Aquaporin protein makes a water channel through the cell
(plasma) membrane.
The function of Aquaporin is to allow
the passive diffusion of water across
the cell membrane. The structure of
Aquaporin is a donut and water goes
through the donut hole.
Aquaporin increases the rate of
osmosis.
Chapter 3 is about protein structure and function.
In Chapter 3, the material on pages 63 -69 is not really covered
until after the first test. That means you need to read it now but
you don’t need to study it until after the first test. Also, I will
talk about this material in class but not until after the first test.
The example will we use is the protein Aquaporin.
Major Sites of Expression and Function of Human Aquaporin
Aquaporin-0 Eye: lens fiber cells
Fluid balance within the lens
Aquaporin-1 Red blood cells
Osmotic protection
Kidney: proximal tubule
Concentration of urine
Eye: ciliary epithelium
Production of aqueous humor
Brain: choriod plexus
Production of cerebrospinal fluid
Lung: alveolar epithelial cells
Alveolar hydration state
Aquaporin-2 Kidney: collecting ducts
Mediates antidiuretic hormone activity
Aquaporin-3 Kidney: collecting ducts
Reabsorbtion of water into blood
Trachea: epithelial cells
Secretion of water into trachea
Aquaporin-4 Kidney: collecting ducts
Reabsorbtion of water
Brain: ependymal cells
CSF fluid balance
Brain: hypothalamus
Osmosensing function?
Lung: bronchial epithelium
Bronchial fluid secretion
Aquaporin-5 Salivary glands
Production of saliva
Lacrimal glands
Production of tears
Aquaporin-6 Kidney
Very low water permiability; function?
Aquaporin-7 Testis and sperm
Aquaporin-8 Testis, pancreas, liver, others
Aquaporin-9 Leukocytes
Aquaporin creates a channel
through the cell membrane
that only
lets H 2O
through.
membrane traffic in cells
Some examples of endocytosis and exocytosis:
1) Aquaporin-2 in human kidney cells
2) neurotransmitter vesicles in all human nerve cells
3) phagocytosis of bacteria by human white blood cells
4) receptor-mediated endocytosis and
cholesterol traffic in humans
membrane traffic in cells
Some examples of endocytosis and exocytosis:
1) Aquaporin-2 in human kidney cells
2) neurotransmitter vesicles in all human nerve cells
3) phagocytosis of bacteria by human white blood cells
4) receptor-mediated endocytosis and
cholesterol traffic in humans
membrane traffic in cells
Some examples of endocytosis and exocytosis:
1) Aquaporin-2 in human kidney cells
2) neurotransmitter vesicles in all human nerve cells
3) phagocytosis of bacteria by human white blood cells
4) receptor-mediated endocytosis and
cholesterol traffic in humans
membrane traffic in cells
Some examples of endocytosis and exocytosis:
1) Aquaporin-2 in human kidney cells
2) neurotransmitter vesicles in all human nerve cells
3) phagocytosis of bacteria by human white blood cells
4) receptor-mediated endocytosis and
cholesterol traffic in humans
Low-density lipoprotein (LDL) belongs to the lipoprotein particle family.
Diameter is about 22 nm,
Mass is about 3 million Daltons (one Hydrogen atom = 1 Dalton)
But vary in size (A few large LDL are healthier than many small LDL.)
Each LDL contain:
1) one B-100 protein molecule (It’s big: 4536
amino acid residues) B-100 binds to the
LDL receptor on cells.
2) a highly-hydrophobic core consisting
of linoleate, a fatty acid, and about
1500 cholestrol molecules
3) surrounded by a shell of phospholipids