Bellringer-1/22/161. 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 BiologyWhat is Life?

BiologyBiology 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 energycycles 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, decomposer,

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!

• Carbon circulates through the atmosphere and

organisms

• Plants take in carbon dioxide through photosynthesis

and release oxygen; animals inhale oxygen and

exhale CO2

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 Warming-human activities (like burning fossil

fuels) are increasing CO2 levels

•How do you think this would affect the carbon cycle?

• Think about it: How does the destruction of the ozone layer

relate to global climate change?

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

• 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. Automatic behaviors, like moths traveling

toward the light or babies suckling, are

examples of what type of behavior? Why are

these behaviors important?

2. Explain Pavlov’s dog. How does this relate to

learned behavior?

3. Explain how this video clip relates to what you

have learned about behavior.

• 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

• 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

• Invasive species-not a natural part of the ecosystem

• Invasive species have no natural predators

• Reproduce out of control!

• Ex. The Kudzu vine

• Acid rain effects-pollution can react with the atmosphere to

produce acid rain; can affect many areas!-destroys plant life

• Beach erosion

• Urban development in Piedmont-leads to habitat destruction

• Waste lagoons on hog farms-hog waste contaminates streams

and drinking water

• 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?