Transcript GHSGT Science Review

GHSGT
Science Review
Day 1-Biology
Mrs. M. Davis
Mrs. K. Rigdon
GHSGT Science Review—2006
Animal Cell
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Plant Cell
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Homeostasis

The maintenance of a stable internal
environment, by regulating substances
traveling into and out of the cell.
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Passive Transport
Osmosis = the unregulated movement of
water across the cell membrane
 Does not require energy to take place
 Cellular response in 3 types of solutions:

– Isotonic = same conc. materials as the cytoplasm
– Hypertonic = greater conc. of materials than the
cytoplasm
– Hypotonic = lesser conc. of materials than the
cytoplasm
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Examples—Animal cell
GHSGT Science Review—2006
Example—Plant Cell
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Organic Compounds
Carbohydrates = used for short-term
storage of energy and fuel (converted to
ATP)
 Fats = used for long-term storage of energy
and fuel (also eventually converted to ATP)
 Proteins = used for growth and repair of
cells and tissues. Many proteins function as
enzymes, allowing physiological reactions to
occur (no reaction = NO LIFE!)
 Nucleic acids (DNA, RNA) = store
information for reproduction of cells
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DNA
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
DNA = deoxyribonucleic acid
shape = twisted ladder (double helix)
– Backbone (sides of ladder) = alternating sugars
and phosphates
– Rungs of ladder = nitrogen bases (C, G, A, and T)
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DNA vs. RNA

DNA = A, T, G, C,
double helix
– A bonds to T, G
bonds to C

RNA = A, U, G, C,
single strand
– RNA bonds to
DNA to read the
genetic code
– A bonds to U, G
bonds to C
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DNA Replication

Replication = DNA copies itself during
mitosis, meiosis
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DNA Replication con’t.
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Genetics
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
Gene = sequence of 3
base pairs in DNA,
controls traits in all
living things
Can be one of two types
(alleles):
– Dominant = always
expressed in phenotype
– Recessive = only
expressed when there is
no dominant gene
present


Homozygous = 2 of
the same allele (RR, rr)
Heterozygous = 1 of
each type of allele (Rr)
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Genetic Crosses

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R
r
Punnett Square =
R RR Rr 3 red (RR, Rr)
allows prediction of
traits in offspring from r Rr rr : 1 white (rr)
parent’s known traits
RT Rt rT rt
Monohybrid cross =
shows offspring that
RT RRTT RRTt RrTT RrTt
would results from 2
Rt RRTt RRtt RrTt Rrtt
heterozygous parents
for 1 trait
rT RrTT RrTt rrTT rrTt
Dihybrid cross = 2
rt RrTt Rrtt rrTt rrtt
parents heterozygous
9 red/tall : 3 red/short :
for 2 traits
3 white/tall : 1 white/short
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Cellular Reproduction

Mitosis
-somatic (body)
cell reproduction
-conserves original
chromosome
number (diploid)
-produces
daughter cell
identical to parent
-Interphase is a
period between
cell divisions for
resting & growth.
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Cellular Reproduction

Meiosis
– occurs in reproductive organs
– produces gametes
(sex cells)
containing ½ the
chromosome
number (haploid)
of the parent cell
– requires two cell
divisions in order to
reduce original
chromosome
number by ½
(haploid)
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Classification
Taxonomy = study of how
organisms are named and
classified.
 System is from most general
to most specific: Kingdom
PhylumClassOrder
FamilyGenusSpecies
“King Phillip Comes Over
For Great Spaghetti.”
 Binomial Nomenclature =
scientific name for organism;
consists of Latin genus &
species designations
ex: humans = Homo sapiens
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Crossing Over

crossing over = varies the genetic
information of the offspring
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Five Kingdoms
Mushrooms,
Yeast
Athlete’s foot
Bread Mold
Euglena,
paramecium
Bacteria, virus
blue-green algae
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Biomes (Ecology)

Aquatic = marine (saltwater) and freshwater
– Majority of world’s oxygen produced by
phytoplankton here

Terrestrial (from coldest to warmest)
–
–
–
–
–
Tundra = temp never above zero
Taiga = coniferous forest (think Canada)
Grassland = prairies and savannah
Desert = arid (very dry)
Temperate = deciduous forest (trees lose leaves)
Think Georgia!
– Tropical = Rain forest, lots of rain, 80 degrees
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Biomes
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Resources

Non-Renewable = any resource that is
used faster than it can be replaced
– Fossil fuels (coal, oil, natural gas)
– Metal ores (copper, aluminum, iron)
– Building materials (rock, such as granite,
limestone, sandstone, marble)

Renewable = any resource that can be
continually replaced or used
– Solar/wind/geothermal/nuclear energy
– Plants and animals (biomass)
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Communities
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Niche = role an organism plays in its environment
Habitat = where the organism lives
Feeding Relationships
– Producers:
• Autotrophs = makes its own food (plants)
• Heterotrophs = must obtain food elsewhere
(animals)
– Consumers:
• Herbivore = eats autotrophs
• Carnivore = eats herbivores
• Decomposer = breaks down organisms
• Omnivore = eats everything above
 Predation = one organism kills another in order to consume
them for energy (animal-animal relationship)
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Communities, con’t.
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Living relationships
– Commensalism = one organism benefits, the
other is unaffected
– Mutualism = both organisms benefit
– Parasitism = one organism benefits, the other is
harmed
• Kudzu is a parasite
In 2000, the City of Tallahassee implemented a program that uses sheep to “mob-graze” kudzu, an
efficient and effective method of eliminating the invasive vine. The program is saving hundreds of
acres of native plants and trees from destruction without using pesticides or heavy labor.
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Energy Flow (Ecosystem)
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