Download HGSS Chapter 2: The Cell

Cell Wall
Endoplasmic
Reticulum
Ribosomes
Cytoplasm
Chromosomes
Nucleus
Mitochondria
Cell Division:
1) Mitosis-ordinary cell division
2) Meiosis-gamete cell division
Mitosis:
Ordinary cell division
Mitosis:
I. Chromosomes are expanded into long
structures in the nucleus and are invisible
under the light microscope.
Mitosis:
II. Chromosomes replicate and condense. With
appropriate staining, they can now be seen
under a microscope.
Mitosis:
III. The nuclear wall degrades, spindles form
and attach themselves to the chromosomes.
Mitosis:
IV. Spindles pull the chromosome pairs apart,
pulling them to opposite poles of the cell.
Mitosis:
V. Nucleus develops around each set of
chromosomes and the cell wall starts to form,
splitting the cell.
Mitosis:
VI. Nucleus and cell wall complete development
and chromosomes expand, giving two daughter cells.
Meiosis:
Cell Division
Generating Gametes
Meiosis:
I. As in mitosis, chromosomes
replicate and condense.
Meiosis:
II. Unlike mitosis, the maternal (solid) and
paternal (dotted) chromosomes pair up
and exchange genetic material.
Meiosis:
III. Spindles form, attach themselves and
pull the chromosomes to the poles of the cell.
Meiosis:
IV. The cell divides.
Meiosis:
V. Spindles form again and pull each
chromosome away from its partner.
Meiosis:
VI. Each cell divides again, reducing the number of
chromosomes to half that of the original cell.
Cell Workings:
Metabolism &
Catabolism
Key Concepts:
1) Lock & Key
2) Cut or Paste
1. Substrate and enzyme
substrate
2. bind together, forming a
substrate-enzyme complex.
enzyme
3. A chemical reaction occurs,
4. leaving a product when the
enzyme dissociates.
product
Tyrosine
tyrosine
hydroxylase
DOPA
(dihydroxyphenylalanine)
DOPA
decarboxylase
DA
(dopamine)
dopamine
b hydroxylase
NE
(norepinepherine)
Cell Communication:
Key Concepts:
1) Lock (Receptor) & Key (Hormones,
Neurotransmitters)
2) Turn on or turn off
The Neuron
Terminal
Dendrites
Cell
Body
Axon
Nucleus
Buttons
Glial Cell
Neurons
© DennisKunkel: www.DennisKunkel.com
Synaptic Button
Vesicle
Neurotransmitter
molecules
Receptor
Vesicle
1. Neuron fires.
2. Vesicles release
neurotransmitter which
exits the cell.
Neurotransmitter
3. Neurotransmitter
binds with receptor
initiating a cascade
of chemical events
in the next cell.
Presynaptic
Neuron
Enzyme
Presynaptic
Receptor
4. Excess neurotransmitter chewed up by enzymes
and/or taken back by the neuron
where it may also be degraded
Enzyme
by enzymes.
Postsynaptic
Receptor
Postsynaptic
Neuron
http://www.drugabuse.gov/pubs/teaching/teaching4/largegifs/slide10.gif
http://www.driesen.com/neurotransmitter_processes.jpg
Effects of
neurotransmission:
1) Short term = ion transfer
(changes polarity of postsynaptic neuron)
2) Long term = second messenger system
(changes proteins, turns genes on/off)
Ions
Neurotransmitter
Receptor
Enzyme
Activating
Ion Channel
Ion Channel
Ions
Neurotransmitter
Receptor
Scaffolding
Molecule
Ion Channel
Second Messenger Molecule
Signal to Cell