Transcript Lesson 2: Energy Flow Through Ecosystems

Lesson 2: Energy Flow
Through Ecosystems
Physical Aspects in an Ecosystem

BIOTIC FACTORS
Bio means “life”
Living organisms
Plants
Animals

ABIOTIC FACTORS
“A” means “not
Not living things
Rocks
Wind
Sun
Water
Dirt
Symbiotic Relationships
• Mutualistic: both partners benefit
• Commensalistic: one partner benefits and the other
partner doesn’t care
• Parasitic: one partner benefits and the other is
harmed
• Predatory: predator/prey…one partner is the dinner
for the other
10 % Rule
Only 10 % of the energy or biomass at one
trophic level is passed on to the next
Wheat
Mouse
Snake
Owl
A food chain, shown above, shows one path the
energy can take.
A food web is a
collection of
several food
chains, linked
together.
A food (or energy) pyramid is
another way to represent this
information. The pyramid
gets its shape from the fact
that the greatest amount of
energy in the ecosystem is
stored in the producers.
(There is more grass than
grasshoppers, and there are
more grasshoppers than
frogs.) There are very few
tertiary consumers in
ecosystems because it takes a
lot of energy feed one.
Toxins(poisons) can
build up in the food
chain. They are
the least
concentrated in
the producers, but
can build up in the
bodies of animals
as they feed. The
higher an animal is
on the food
pyramid, the more
poision he has
consumed.
Lesson 4: Viruses and Bacteria
Viruses
• ARE NOT LIVING!
• Only can reproduce inside host cell
• Cell Specific- will only bind to certain cells
– Polio virus only attaches to human nerve cells
Viruses
• Viral infection must run their course- NO
ANTIBIOTICS!
• There are vaccines that can prevent some
viral infections, like Hepatitis A or B,
influenza and chicken pox.
• An organism’s immune system is designed
to fight viruses with fever & antibodies.
Viruses destroy host cell!!
Viral diseases
• HIV/AIDS: Destroys Helper T cells of the
immune system
• Influenza and common cold: spread by
contact
Bacteria shapes
A. Coccus: round or spherical
B. Spirillum: spiral-shaped
C. Bacillus: rod-shaped
Coccus
Bacillus
Spirillum
Bacterial arrangements
Diplo- : paired cells
Staphylo- : grapelike clusters
Strepto- : long chains
Diplo-
StaphyloStrepto-
Bacteria
Good Types
• Used in Nitrogen cycle
(Rhizobium)
• In food (lactobacillus)
• In digestive system
(E. coli)
• Decomposers
Bad Types
• Cause disease
– Strep throat
– Diphtheria