Biology CST Review - 2012

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14 Δεκ 2012 (πριν από 4 χρόνια και 8 μήνες)

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Ecology

Physiology



ECOLOGY

How organisms relate to each other
and to their surroundings.




The total number of different species to inhabit one area.
The more the species, the more will survive in case of
disasters to the habitat.

Biodiversity

6a:
Students know
biodiversity is the sum total of different kinds of organisms and
is affected by alterations of habitats.




Natural ecosystems can undergo many alterations
and can make necessary changes to accommodate
them. Sometimes, alterations are too great and
nature cannot recover.


Climate



ice age, drought


Human activity


pollution, destruction


Nonnative species


organism that is not native to area,
usually has no natural predators & grows unchecked


Population size


too many deaths or births or migration

Ecosystem Changes

6b:
Students know
how to analyze changes in an ecosystem resulting from changes
in climate, human activity, introduction of nonnative species, or changes in
population size.



Succession


Order of life inhabiting an area


always smallest to
biggest

6b:
Students know
how to analyze changes in an ecosystem resulting from changes
in climate, human activity, introduction of nonnative species, or changes in
population size.




Population is the total amount of one species in
a given area. The change in the size of the
population is determined by four factors:


Birth rate


number of organisms born & surviving


Death rate


number of organisms dying


Immigration



number of organisms moving INTO
area


Emigration



number of organisms moving FROM
area

Population Size

6c:
Students know
how fluctuations in population size in an ecosystem are
determined by the relative rates of birth, immigration, emigration, and death.

Population
Size

BIRTHS

Immigration

DEATHS

Emigration




Biogeochemical Cycles

6d:
Students know
how water, carbon, and nitrogen cycle between abiotic resources
and organic matter in the ecosystem and how oxygen cycles through photosynthesis
and respiration.




Food Chains & Webs


What eats what?


Producers

(plants)


Consumers

(animals


herbivores, carnivores,
omnivores)


Decomposers

(bacteria, fungi)


eat any dead
organism


Producers, Consumers, Decomposers

6e: Students know a vital part of an ecosystem is the stability of its producers and
decomposers.




Organisms only obtain 10% of energy from what they eat.
90% is released as heat.


Source of all energy is the sun!

Energy Pyramid

6f:
Students know
at each link in a food web some energy is stored in newly made
structures but much energy is dissipated into the environment as heat. This
dissipation may be represented in an energy pyramid.



BIOTECHNOLOGY

Manipulating the genes of an organism to
produce different results.




Humans directly manipulating an organisms
genome, usually for the benefit of people


Ex: manufacturing human insulin for people with
diabetes


Ex: adding vitamin A to rice to prevent blindness

1.
Remove needed gene from human DNA

2.
Insert gene into bacterial DNA (plasmid)

3.
Insert hybrid plasmid into bacterium

4.
Bacteria undergoes transcription & translation to
produce desired protein

Genetic Engineering

Standard 5c:
Students know
how genetic engineering (biotechnology) is used to
produce novel biomedical and agricultural products.



PHYSIOLOGY

The study of how an organism functions
through its organ systems.



In with the Good, Out with the Bad

9a:
Students know
how the complementary activity of major body systems
provides cells with
oxygen
and
nutrients
and removes
toxic waste
products such
as
carbon dioxide
.


Circulatory
: transport
nutrients
,
wastes (
CO
2
),
hormones, and
gases
throughout body systems;
maintains homeostasis


Digestive
: extract & absorb
nutrients
from
food;
remove wastes; maintains water & chemical
balances


Excretory
: removes
wastes
from blood; regulates
concentration of body fluids


Respiratory
: move air into/out of lungs; controls
CO
2
/
O
2

exchange between blood & lungs


Nervous
: controls sensory & motor functions;
regulates behavior & organ systems


Muscular
: moves substances through body;
provides movement, structure, & support



Nervous System

9b:
Students know
how the nervous system mediates communication between
different parts of the body and the body’s interactions with the environment.


controls sensory functions



when 5
senses

(sight,
touch, taste, smell, hearing) get
stimulus

from
external
environment
, information goes up to
brain

through
nerves

and gets processed



regulates behavior & organ systems
-

if
response

is
required (swatting fly), information goes back down
nerves to responding organ system (muscular &
skeletal)



Feedback Loops

9c:
Students know
how feedback loops in the nervous and endocrine systems
regulate conditions in the body.


Feedback loops can be
positive

(
continue

response
that stimulus triggers) as in
childbirth
,
breast
feeding
,
blood clotting


Both
endocrine

(hormones) and
nervous

(brain &
nerves) systems
regulate

homeostasis by using
feedback loops

Stimulus

Regulated
Factor

Detector

Response

Brain

Skin Receptors

Sweating


Human body wants to
maintain

all systems via
process called
homeostasis

(staying same)



If homeostasis
disrupted
, will employ responses to
get back to
original state


Nearly all feedback loops are
negative

(
stop

response that stimulus triggers) as in
hunger

and
thirst
, and
temperature

changes

Hot 100
°
F
Day

Bleeding

Blood Clots

Blood Vessel
Receptors

Body
Temp.

Feedback Loop

Normal
Temp


Platelets



Electricity in the Body

9d:
Students know
the functions of the nervous system and the role of neurons in
transmitting electrochemical impulses.


Nervous system is made of nerve cells, also
called
neurons


Typical neuron contains
dendrites

(receive
messages),
cell body
(location of nucleus),
axon

(communication cable), &
axon
terminals
(send messages
)

Chemical (dendrites)

Electrical (body & axon)

Chemical (axon terminals)


Messages
or communication is transmitted
via
electrochemical impulses

o
Chemicals called
neurotransmitters

attach to dendrite
receptors

o
Electrical pulse
sent through cell body
down axon

o
Chemical neurotransmitters sent out
of
axon
terminals to other neurons at
synaptic cleft

(space in between two
neurons)



Neurons

9e:
Students know
the roles of sensory neurons, interneurons, and motor neurons
in sensation, thought, and response.


Nervous system divided into two
categories:


1.
central nervous system (CNS)
=
brain & spinal cord


Control center of body made of
interneurons

(neurons that gather
information from inside body
)


2
.
peripheral nervous system
(PNS)
= sensory neurons &
motor neurons


Sensory neurons
: send info
to
brain from
5
senses (up)


Motor neurons
: send info
from
brain to muscles or
organs to carry out
response
(down)



Infection and Immunity

10a:
Students know
the role of the skin in providing nonspecific defenses against
infection.


Skin (integumentary system)
is first line of
nonspecific
defense

in protecting body
against
any

foreign invader
(
pathogen
) that can cause
infection (usually viruses or
bacteria) since it provides a
barrier


Break in skin barrier allows
pathogen

to enter & infect


Second line of
nonspecific
defense

is
phagocytosis

(white blood cells that eat
invader)



Infection and Immunity

10b:
Students know
the role of antibodies in the body’s response to infection.


If phagocytes cannot prevent
pathogen

from infecting, body undergoes
specific
defense

in which it identifies and targets
specific
pathogen


Pathogen is now considered an
antigen

since it causes immune
response (usually a virus)


Body produces specific Y
-
shaped
proteins called
immunoglobulins

(
Ig
) or
antibodies

(
ANTI
-
body
) to kill
antigen

(
ANTIbody

GENerator
) using lock &
key mechanism (antigen = key, antibody
= lock)




Antibody is produced when
helper T
-
cell
(from Thymus)
causes
B
-
cells

(from Bone) to
construct
specific

antibody


Antibodies bind to antigen, now
phagocytes can eat and destroy
them


Entire process takes 7
-
10 days


Some B cells turn into
Memory B
cells
that will always be prepared
to
immediately

kill same antigen so
that individual never experiences
symptoms






Vaccines

10c:
Students know
how vaccination protects an individual from infectious
diseases.


A
vaccine

is an injection of
weakened

or
dead

antigen into the body


The immune response produces antibodies as body can’t tell it’s
harmless.


Antibodies with phagocytes destroy antigens


Memory
-
B cells permanently remember antigen so if body encounters it
again, immediate attack occurs
before disease symptoms develop

making individual
immune

from disease



Bacteria & Viruses

10d:
Students know
there are important differences between bacteria and viruses
with respect to their requirements for growth and replication, the body’s primary
defenses against bacterial and viral infections, and effective treatments of these
infections.


A
microbe

is anything too small to be
visible to the naked eye. Two types of
microbes are
bacteria

and
viruses
.


Viruses
may
have a spiny outside
layer, called the
envelope
. Viruses
have a core of genetic
material
(
DNA

or
RNA
),
but
cannot
reproduce
on their own. They
infect cells and take over their
reproductive machinery to
reproduce
.
They are not considered
living.


Bacteria

are single
-
celled
prokaryotic living organisms




Bacterial infections can be
treated with the
non
-
specific

immune
response

or
antibiotics
, medicines that
destroy prokaryotic bacteria
without harming eukaryotic
humans


Viruses cannot be treated
with any medicines, solely the
immune response




Compromised Immunity

10a:
Students know
why an individual with a compromised immune system (for
example, a person with AIDS) may be unable to fight off and survive infections
by microorganisms that are usually benign.


If the immune system is compromised
or not working, individual may not be
able to survive simple infections like
flus or pneumonia


In AIDS (Acquired Immune Deficiency
Syndrome), T
-
helper
cells are infected
by
HIV (Human Immunodeficiency
Virus),
thus weakening
immune
system


AIDS patient usually dies from
pneumonia