Upload
others
View
1
Download
0
Embed Size (px)
Citation preview
Bellringer-1/21/16
On a sticky note, brainstorm 3
important lab safety rules that must
be followed in a classroom lab.
Independent vs. Dependent Variable
Independent Variable- is changed or controlled in a scientific experiment to test the effects on the dependent variable.
Dependent Variable- Something that depends on other factors. It is what is being tested and measured in a scientific experiment.
Example: Does brightness of light have any effect on moth attraction?
Light Level= Independent
How moth reacts=Dependent
Bellringer-1/22/16 1. What is Biology?
2. What characteristics classify something as living?
3. A bird watcher records the movement of migrating birds. In which part of the scientific process is the bird watcher participating?
a) Controlling variables
b) Experimenting
c) Observing
d) Hypothesizing
Introduction
to Biology What is Life?
Biology Biology is the study of living
organisms
“Bio” means “life”
What do you think it means
to be living?
The Characteristics of Life Living organisms…
Are made of cells
Obtain and use energy
Grow and develop
Reproduce
Respond to their environment
Adapt to their environment
We are going to look at all of
these characteristics this
semester!
The study of ecosystems
• Ecosystems are communities of living organisms in
relation to all the nonliving components within them
• These are called biotic and abiotic factors
• Nutrients are recirculated through organisms and their
surrounding environments
• Energy cycles within ecosystems include:
• Carbon Cycle
• Nitrogen Cycle
•Water Cycle
• But first we’re going to look at how energy cycles
through an ecosystems…
• Autotrophs-make their own food using CO2 to make glucose
(sugar) producers
• Heterotrophs-have to eat other organisms to gain energy
consumers
• Think about it: What adaptations do carnivores have for
survival? Herbivores? Omnivores?
Omnivores eat both
meat and plants
(Ex. Human, bear)
Herbivores eat only
plants (Ex.
Grasshopper,
rabbit, cow)
Carnivores eat only
meat(Ex. Owl,
shark, tiger)
• Decomposers-break down dead, organic matter
Notice in this food chain,
bacteria serves as the
decomposer when the
organisms die. Other
examples include fungi
(like mushrooms) and
earthworms.
FOOD CHAIN
• One pathway of energy flow
FOOD WEB
• All the possible pathways of
energy flow
• Energy flows through ecosystems
• Food chains and food webs show how energy originating in the
sun travels through organisms
• Arrows always point in the direction of energy flow!
• The energy that travels from the sun is called radiant energy
• This travels in the form of electromagnetic waves. The sun is a natural
source of radiant energy!
• Plants then use photosynthesis to convert radiant energy from
the sun to chemical energy in the form of glucose (sugar)
• Autotrophs are a crucial part of the food web! Without them, we could
not gain energy!
• Think about it: What is the difference between radiant energy
and thermal energy?
• Radiant energy travels directly from the sun via waves. Thermal
energy is energy that comes from heat. The two can be related, but
are not the same!
• During the transfer of energy, only 10% is stored as
you move through each level. The rest is lost to
respiration, digestion,etc.
• Think about it: Is the sun part of the food chain?
• Yes, it is the energy source of the food chain. But remember, the first
organism in the food chain is always an autotroph (producer)!
Radiant energy of
the sun is the
ultimate source of
energy on Earth!
Autotrophs use
sunlight to make
their food.(radiant
energy converts to
chemical)
Heterotrophs will now gain energy
by consuming other organisms.
Decomposers will
break down dead
material.
1. Imagine you ate steak for lunch. Explain how the energy
you got from that steak originated in the sun!
2. In the food chain below, identify at least 1 example of each
of the following: autotroph, heterotroph, herbivore,
carnivore
3. What could you add to this food web to make the frog an
omnivore?
1. Radiant energy from the sun must be converted into
chemical energy that allows organisms like us to
survive. What key component of the food chain
converts that solar energy into chemical energy?
2. Create a simple food chain of at least 4 organisms.
Using arrows, identify the direction that the energy
travels as it moves through the chain.
• Nitrogen cycles through the environment in various
chemical forms
•All organisms require nitrogen to live and grow
• 78% of nitrogen is in the atmosphere-it must be
converted to a usable form!
• Nitrogen Fixing Bacteria-Microorganisms that converts
nitrogen from the atmosphere into fixed nitrogen in the
soil (usable form) for other plants to use
Nitrogen Fixing Bacteria
• The nitrogen cycle mostly
takes place underground
• Nitrogen fixation: bacteria
(in soil or on plant roots)
convert N2 gas to
ammonia
• Ammonia is released in the
soil and transformed into
ammonium
• Nitrifying bacteria change
the ammonium to nitrate
• Decomposition returns
nitrogen to the soil!
Think about it: In what two
locations would you find nitrogen
fixing bacteria?
• Carbon circulates through the atmosphere and
organisms
• Plants take in carbon dioxide through photosynthesis
and release oxygen; animals inhale oxygen and
exhale CO2 through respiration
The Carbon Cycle
moves carbon dioxide
from the atmosphere,
through the food web,
and returns to the
atmosphere.
HUMAN PROCESSES
• Global climate change (human influenced increase in the greenhouse effect!)
• Humans release CO2 through a number of factors, including the burning of fossil fuels
NATURAL PROCESSES
• Volcanic Eruption-volcanoes naturally emit CO2 when eruptions occur
• Geological processes
• Carbon is a naturally occurring part of our
atmosphere-it is supposed to be there!
• The Greenhouse Effect-a naturally occurring effect that
keeps our Earth warm; we need it to survive!
• Global Climate Change-human activities (like burning
fossil fuels) are increasing CO2 levels
• Think about it: How is global warming related to the greenhouse effect, and what impact might this have on the carbon cycle? • The greenhouse effect is a natural warming of Earth. CO2 is one of
the gases that naturally traps heat to make life possible here on Earth. When humans add CO2 to the atmosphere, the warming is intensified.
• Think about it: How does the destruction of the ozone layer relate to global climate change? • CFC’s in the atmosphere contributed to ozone destruction. As a
result, we are getting less protection from UV rays.
How would the following scenarios impact the carbon cycle?
1. A city bulldozes ten acres of forest to develop a shopping mall.
2. A lumber mill plants two trees for every one that it harvests for wood.
3. Everyone in your neighborhood purchases and uses an additional, gas burning vehicle.
1. What is the difference between autotrophs and
heterotrophs? What role do autotrophs play in the
carbon cycle?
2. What types of environmental concerns are
associated with the burning of fossil fuels?
Hypothesize some methods to reduce these concerns.
• Adaptation-Any trait an organism acquires over time that helps
it survive in its environment
• Can be structural, behavioral, or reproductive
• Structural-Physical features an organism has that help it
survive
• Behavioral-Something an organism does to help it survive
• Reproductive-An organism chooses the “correct mate” to
reproduce and raise offspring
• Transport and Excretion-Organisms maintain balance;
move nutrients into cells and waste out
• In plants: Vascular and nonvascular
Vascular Plants Nonvascular Plants
Vascular tissue contains special
cells for transport of water and
nutrients
Lack of roots and stems means
plants must take water directly
through their cells
Mosses do not
have a vascular
system.
Ferns do have
a vascular
system. (Ex,
Gymnosperms
and
Angiosperms)
• Respiration-organisms take in and release gases (we
will discuss more later)
• Nutrition-feeding adaptations that allow organisms to
get nutrition
Autotrophic Heterotrophic
Organisms that gain energy
through making their own food
(ex. Plants)
Organisms that gain energy
through eating their food (ex. Us!!)
• Reproduction, Growth, and Development-Organisms have
adaptations to distribute their population
Sexual Asexual
Reproduction involving sex
(needs a male and female)
Reproduction without sex (can
be 1 organism)
Example: Seeds have a hard protective coating that allows them to survive some harsh
conditions; some are small/prickly to allow transport
• Behavioral adaptations can be innate or learned
• Innate=“hard-wired;” you are born knowing how to
do this
• Learned=learned behavior either by interacting with
the world or being taught!
• Suckling-Babies are born knowing how suckle;
adaptation allows them to be nourished
• Taxes/Taxis-movement of an organism in response to a
stimulus (ex. Light or food)
• Migration-seasonal movement of animals in response
to resource availability
• Estivation-dormancy during the warm season
• Hibernation-dormancy during the cold season
• Habituation-an animal stops responding to a stimulus after too
much exposure
• Imprinting-Baby recognizes something as parent/objet of trust
• Classical conditioning-Learning a new behavior through
association (ex. Pavlov’s dog)
• Trial and Error-Animal associates behaviors with the
consequences they produce
1. Explain how this video clip relates to what you
have learned about behavior.
2. Explain Pavlov’s dog. How does this relate to
learned behavior?
3. Automatic behaviors, like moths traveling
toward the light or babies suckling, are
examples of what type of behavior? Why are
these behaviors important?
• Atom
• Biome
• Biosphere
• Cell
• Community
• Ecosystem
• Molecule
• Organ
• Organ System
• Organism
• Population
• Tissue
1. Atom
2. Molecule
3. Cell
4. Tissue
5. Organ
6. Organ system
7. Organism
8. Population
9. Community
10. Ecosystem
11. Biome
12. Biosphere
• Predator/Prey-one organism hunts and kills another
organism for food
• Ex. The lion (predator) hunts the gazelle (prey)
• Competition-two organisms compete over a common
resource (food, territory, etc.)
• Symbiosis = organisms living together
• 3 Types of symbiotic relationships
•Mutualism
•Commensalism
• Parasitism
• Mutualism = benefits both organisms in relationship
https://www.youtube.com/watch?v=Xm2qdxVVRm4
• Commensalism = one organism benefits and the other
is unaffected
Note: There is debate that commensalism is just early mutualism! Maybe we don’t understand all
the benefits?
• Parasitism = one organism benefits and the other is
harmed
• PARASITES (like viruses) don’t immediately kill
host… use it first – sometimes kill it later!
https://www.youtube.com/watch?v=qN2XMyxAs5o
• Communication within society using pheromones-bees, ants, and
wasps!
• Ex. Ants use pheromones to determine family members, to
summon for attack/defense, and even to warn other ants when
they are squashed
• Ex. Bees use pheromones to communicate and maintain
organization in their colony
• Courtship Dances-animals sometimes have rituals (may be a
dance, vocalization, or display of beauty/power) in order to
select a reproductive partner
• Territorial Defense-animals may defend their territory against
other organisms, in or outside of their species
• Ex. Male fighting fish will build a nest and maintain that
territory during breeding season, acting particularly
defensive against other males
1. In the animal kingdom, there are numerous species
interactions. Label the following examples as either
predator/prey, competition, or symbiosis. If it is
symbiosis, further categorize as mutualism,
commensalism, or parasitism.
a) A hawk and a fox are fighting for the same food source: rabbits.
b) A hummingbird picks up pollen for a flower and carries it to other
flowers while it is getting nectar.
c) The lion chases down and kills the gazelle for food.
d) Barnacles attach themselves to whales and carry out their lives. The
whale is unaffected.
e) A tick sucks the blood of a dog.
Imagine you have a population of cheetahs and
gazelles.
1. If a disease struck the cheetah population causing a
drastic decline in number, what would happen to the
gazelle population. Explain your answer.
2. If the cheetah population experiences an increase in
birthrate, what would happen to the gazelle population?
Explain your answer.
3. Describe a scenario that would cause an increase in the
gazelle population.
• Carrying capacity-the maximum population size an ecosystem
can hold
• Based on limiting factors like food availability, climate, water, territory
• Predator/Prey relations can help maintain stability
Think about it: What
happens to the
population when it is
over carrying capacity?
Under?
• What is the main difference between a population with an exponential graph vs. a logistic graph?
• Think about it: Under what circumstance(s) does an organism experience logistic growth? Exponential growth?
What happens to
prey populations
as prey increases?
Decreases?
Which population is growing fastest?
• What effect do you think the following would have on
the population?
• Birth/death rates
• Lack of resources
•Diseases (like AIDS or tuberculosis)
• Density Dependent Factors = factors in the ecosystem that can change as a result of the population density (# of organism in an area)
• Examples:
• Food
• Shelter
• Water
• Disease
• For example, more organisms might mean less food
• Think about it: How do the terms limiting factor and density dependent factor differ?
1. Draw a graph that illustrates a population that
experiences logistic growth.
2. Label
- The area of exponential growth
- Carrying capacity
3. List three limiting factors that can force a population
to stabilize.
1. Male peacocks spreading their feathers to impress a mate is
which type of adaptation?
a) Structural
b) Behavioral
c) Reproductive
d) Embryological
2. In a forest ecosystem, which is an abiotic factor?
a) The amount of rainfall
b) The size of the deer
c) The type of trees
d) The number of birds
• Humans have a large impact on ecosystems
• Population growth has led to destruction of habitats
•We use resources (trees, oil, coal, etc.)
•More humans=more waste
•Deforestation =human removal of trees; increased
CO2 leading to global warming
• Pesticide Use
• Bioaccumulation-as pollutants move through a food
chain, they tend to concentrate as they move from one
level to the next
Organism Name Total # of food in
stomach
Total # of toxic
food (red and
orange)
Percentage of Toxic
Food Consumed
1. Did the seal survive the toxins? Why or why not?
2. What percentage of the entire food chain died as a
result of the toxins?
3. Why did some animals survive the toxins?
4. In your own words, define “bioaccumulate.”
5. Oysters are animals that filter food particles like
plankton from the water. How could dining on oysters
during a harmful algae bloom, which produces the
toxins, affect a person’s health? Explain your answer.
• Invasive species-not a natural part of the ecosystem
• Invasive species have no natural predators
• Reproduce out of control!
• Ex. The Kudzu vine
• Think about it: What are some specific factors that influence NC
ecosystems?
1. Acid rain effects-pollution can react with the atmosphere to
produce acid rain; can affect many areas!-destroys plant
life
2. Beach erosion
3. Urban development in Piedmont-leads to habitat destruction
4. Waste lagoons on hog farms-hog waste contaminates
streams and drinking water
Deforestation
Impact: Increased CO2,
Increased Erosion
Solution: Replanting
Burning Coal
Impact: Increased CO2,
Global Climate Change
Solution: Alternative
Energy Sources
Using Oil
Impact: Increased CO2,
Climate Change,
Environmental Harm
Solution: Alternative
Energy Sources; bacteria
to clean up spills
Agriculture
Impact: Use of
pesticides, salinization
in soil
Solution: Good practice
(crop rotation)
• Habitat and species preservation
• “Endangered Species Act”
• Zoology and Reintroduction Programs
• Nature preserves
• Reaching Sustainability
• Using resources wisely
• “Reduce, Reuse, Recycle”
1. Explain why it is a poor idea to release your pair of
aquarium lionfish into the Currituck Sound.
2. Explain why parents should limit the amount of tuna
that young children consume.
3. Explain how acid rain is produced and why it is a
problem in areas outside of the origin of the
pollutant.
1. What could happen if the human population
continued to grow exponentially? Think about it in
terms of limiting factors, like natural resources.
2. What is an invasive species? Why are they a
concern?
3. What is bioaccumulation?