Chapters 1, 3, 8 & 9

Big Idea: Why am I Big & Full of

Energy?

Or

Why am I made of my grandma’s

feces?

What is Biology?

Biology – the study of

life

Involves many aspects:

ecology, cellular

biology, biochemistry,

molecular biology,

genetics, evolution,

zoology, botany, etc.

Francesco Redi Spontaneous generation – the idea, accepted

for centuries, that life appears

spontaneously

Redi, an Italian scientist, did an experiment

to try and disprove this

John Needham

English scientist who did an experiment

to dispute Redi’s results

Lazzaro Spallanzani

Assumed that

Needham didn’t

heat his broth

enough to kill

microbes

Louis Pasteur

French scientist

who finally

disproved idea of

spontaneous

generation (150

years after Redi)

Characteristics of Living Things

1. Cell or cells that function together

2. Based on a Universal Genetic

Code

Contain DNA or RNA

3. Reproduction

The production of offspring is not essential

to an individual organism, but for the

continuation of a species

Can be sexual or asexual

4. Grow and Develop

Growth results in an

increase in the amount of

living material and the

formation of new

structures

Development is all of the

changes that take place

during the life of an

organism

5. Respond to Environment Environment – an organism’s surroundings, including

air, water, weather, temperature, and many other

factors

Stimulus – anything in an organism’s external or

internal environment that causes the organism to react

Response – reaction to a stimulus

6. Maintain a stable internal

environment

Homeostasis – regulation of an organism’s

internal environment to maintain conditions

suitable for survival

Done by using energy

7. Evolve

Evolution –the gradual change in a species through adaptations over time

Review

What is biology?

What are 4 characteristics of living things?

How are living things organized?

Which characteristic of living things is essential to a species, but not to an individual?

Give an example of a stimulus and response in nature?

What is homeostasis?

What is evolution?

What is Ecology?

Ecology – the

scientific study of

interactions among

organisms and their

environments. Reveals relationships

among living and

nonliving parts of the

world

Levels of Organization in Ecology Organism - anything that possesses all

the characteristics of life

Population – a group of organisms of one species that interbreed and live in the same place at the same time

Ex: All the bass in Utah Lake, the elk near Hardware Ranch

They may compete for resources, mates, etc. if there are limitations

Community – a collection of interacting populations

Ex: everything alive in Utah Lake or near Hardware Ranch

Communities may also compete for resources, or may even be dependent on each other for food, needed gasses, etc.

Levels of Organization in Ecology

Ecosystem – made up of the interactions among the populations in a community and the community’s physical surroundings, or abiotic factors

Three Kinds: terrestrial, freshwater aquatic, saltwater aquatic (marine)

Biome – similar ecosystems that share a similar ecosystem

Biosphere – the portion of Earth that supports life

Coral Reefs are a rich,

diverse and productive

ecosystems

A coastal wetland on Lake

Superior, Wisconsin.

Photo by K. Rodriquez

Review

What is ecology?

List the 5 levels of study in ecology (in order)

Explain population in ecology and give an example.

Explain community in ecology and give an example.

Explain ecosystem in ecology and give an example.

How Organisms Obtain Energy

All energy originates from

the sun

Autotrophs – organisms

that use the energy from

the sun (photoautotrophs)

or energy stored in

chemical compounds

(chemoautotrophs) to

manufacture their own

nutrients

Heterotrophs Organisms that cannot make their

own food and must feed on other organisms

Herbivores – feed on autotrophs

Carnivores – eat other heterotrophs

Omnivores – feed on both autotrophs and other heterotrophs

Scavengers – eat animals that have already died

Decomposers – break down and absorb nutrients from dead organisms (not eating, absorbing)

Food Chains Matter & energy flow

through organisms in

ecosystems (law of

conservation of energy)

Food Chain – a simple

model that shows how

matter and energy move

through an ecosystem

(what eats what) Give me an example

There is less energy at each

successive step of the food chain

Food Web Expresses all the possible

feeding relationships at each trophic level in a community

More realistic than a food chain because organisms depend on more than one other species for food

As you draw a food web, the arrows represent the direction of energy flow

Pg. 51 of book

Trophic Levels

Each organism in a food chain represents a feeding step, or a trophic level, in the passage of energy and materials

1st trophic level – autotrophs

2nd trophic level - 1° heterotrophs Herbivores, omnivores, decomposers, scavengers

3rd trophic level - 2° heterotrophs Omnivores, carnivores, decomposers, scavengers

4th trophic level - 3° heterotrophs Omnivores, carnivores, decomposers, scavengers

Ecological Pyramid Shows how energy flows through an

ecosystem

10% Rule: only about 10% of all energy can

be passed from one trophic level to the next

Producers (1025 Joules)

2° Consumer (11 Joules)

3° Consumer (1 Joule)

Pyramid of Energy

1° Consumer (98 Joules)

Pg. 52

Review What is the difference between a photoautotroph

and a chemoautotroph?

What are the 5 types of heterotrophs?

Give an example of a food chain with at least 4 organisms.

What is the difference between a food chain and a food web?

What is a trophic level?

What is the 10% rule?

What shape are ecological pyramids?

You & the Web of Life

Assignment

Bottle Ecology

ATP - Life’s Energy

Adenosine triphosphate

ATP stores energy in the

bonds between adenosine

and three phosphates (which

are charged).

When a bond between

phosphates is broken,

energy is released

Stored by creating bond

Jan van Helmont

Planted a seedling

Measured the mass of soil

Five years later, measured

mass of soil and of tree –

soil mass was unchanged

Concluded that mass of

tree came from water

Joseph Priestly

Lit a candle, put a jar on it and fire went out

Lit a candle, put it under a jar along with a sprig of

mint and the flame continued for a few days

Concluded that there is something in the air

produced by plant - oxygen

Jan Ingenhousz

Showed Priestley’s

experiment only

worked when the

plant was exposed

to light

Photosynthesis

The process that uses the sun’s

energy to make simple sugars

These sugars are then converted into

complex carbohydrates

3 Things needed:

Water

Oxygen

Light

2 Things Produced

Sugar

Carbon Dioxide

6CO2 + 6H20 C6H12O6 + 6O2

The Chloroplast & Pigments

Membranes in chloroplast contain pigments –molecules that absorb specific wavelengths of sunlight

Chlorophyll is the most common pigment

Absorbs most wavelengths of light except green

Light-Dependent Reactions

Light excites (energizes) electrons in the membranes

This energy is used to form ATP from ADP (adenosine diphosphate), which will be used in the light independent reactions

Electrons then combine with some “stuff” to make something called NADPH, which will also be used in the light independent reactions

Why is Water Needed?

Chloroplasts constantly need new electrons

Plants split water to get molecules in a process known

as photolysis (2 electrons per water molecule)

Oxygen is released into the air through little holes in leaves

called stomata (who uses it?)

Light-Independent Reactions The Calvin cycle (Melvin Calvin) is a series of

reactions that use carbon dioxide to form sugars

Uses what was produced in light rxns & CO2 from

atmosphere (comes in through stomata)

To Summarize Light Dependent

Reactions make carbon

dioxide (which is

released), ATP and

NADPH (which store

energy and are used

next)

In the Calvin Cycle,

the energy in the ATP

and NADPH is used to

make glucose (which

plants use as food)

Section Review

Why do you see green when you look at a leaf?

Why do you see other colors in the fall?

What is produced in the light-dependent reactions?

How do the light-dependent reactions of photosynthesis relate to the Calvin Cycle?

What is the function of water in photosynthesis?

What is the end product of photosynthesis?

Is chlorophyll a reactant, product, or neither in photosynthesis?

Cellular Respiration

The process by which mitochondria break down food molecules to produce ATP.

Three stages:

Glycolysis

Citric acid cycle (Krebs cycle)

Electron transport chain

Glycolysis is anaerobic (no oxygen required)

The other two stages are aerobic

Glycolysis

Glycolysis is a series of chemical reactions

in the cytoplasm of a cell that break down

glucose in two

2 ATP are required

4 ATP are made

2 NADH are made

back BACK

Citric Acid Cycle Also called the Krebs cycle

A series of chemical reactions similar to the Calvin

cycle

Each pyruvate (pyruvic acid) loses a carbon and

makes an ATP “on the way” to the Krebs Cycle

Products per turn of cycle (2 turns per glucose)

3 NADH

2 CO2 - then breathed out

1 FADH2

1 ATP - Usable energy

back

FADH2

FAD+

ATP Totals from Aerobic

Respiration

10 NADH molecules = 30 ATP Each NADH leads to 3 ATP

2 FADH2 molecules = 4 ATP Each FADH2 leads to 2 ATP

2 ATP during glycolysis 4 ATP are made, but 2 are used

2 ATP during citric acid cycle 1 per pyruvic acid

GRAND TOTAL = 38 ATP per glucose

Ms. Lowe’s Video

Ms. Lowe’s Video

To Summarize:

Glycolysis:

Breaks down glucose from food

A little ATP is made that can used now

Other energy storing molecules made to be

used later

Krebs Cycle

Use oxygen and CO2 make more high energy

molecules

Electron Transport Chain

Uses energy in those molecules to make ATP

Fermentation Anaerobic process

Follows glycolysis and provides a means to

continue producing ATP until oxygen is

available again

2 major types:

Lactic acid fermentation (lactic acid produced -

in animals, for instance)

Alcoholic fermentation (ethanol & carbon

dioxide produced - yeast)

8

Comparing Photosynthesis and

Cellular Respiration

Occurs in ALL living cellsOccurs only in the presence

of chlorophyll

Doesn’t require lightRequires light

Produces CO2 and H2OProduces sugars from PGAL

O2 taken inO2 given off

Energy of glucose releasedEnergy from sun stored in

glucose

Food broken downFood synthesized

Cellular RespirationPhotosynthesis

Ms. Lowe’s Video

Section Review

How much ATP is made in glycolysis? In aerobic respiration? In anaerobic?

How do alcoholic fermentation and lactic acid fermentation differ?

How is most of the ATP from aerobic respiration produced?

Why is lactic acid fermentation important to the cell when oxygen is scarce?

Who will build up more lactic acid, a jogger or a sprinter?

Cycles of Nature Law of Conservation of Matter

www.BioEdOnline.orgBioEd Online

Water Cycle

www.BioEdOnline.orgBioEd Online

Carbon Cycle

www.BioEdOnline.orgBioEd Online

Nitrogen Cycle

Review

Tell me about the water cycle.

Describe one “path” through the carbon

cycle.

How do we get nitrogen from the ground

and into us?

Why MIGHT you eat your mom’s feces

for lunch today?