Warm Up #1How did the Chapter 23 test compare to

Chapter 1?

Starting with cells, name as many the levels of organization as you can (going up from smallest to largest)

What, to you, mean that something is “living?” What attributes does this thing/person need to have?

Ecology, Ecosystems and Foodwebs

Chapter 4

What’s Life, Anyway?

Checklist of categories:

Enable Growth and Change

Survival

Reproduction

Step 1: Life is made of cellsCells – basic units of life

Discovered by Hooke (cork)

Can be unicellular (bacteria) or multi-cellular (humans)

Each cell contains genetic material (DNA/RNA)

HIV – a beautifully simply viral cell

Step 2: Life has DNADNA =

deoxyribonucleic acid

Instructions for new cell production

Origination of life = RNA (ribonucleic acid)?

Also code for proteinsWhich came first, the DNA or the RNA? Either way, this soup looks pretty gross.

Steps 3 and 4: Life is homeostatic and evolves over timeHomeostasis =

balance internal conditions (negative feedback loop)

Adjusts to changes in outside environment

Evolution – change in genetic composition over time

Step 5: Life “does it”…reproduces that is..Asexual

reproduction (mitosis) – producing identical cells of the parent cell

Sexual reproduction (meiosis) – producing daughter cells with traits of male and female parent cells.

A benefit to asexual reproduction – you never need to worry about the “let’s just be friends” card

Step 6: Life takes matter and makes energy (food. Mmmm, food)Metabolism –a set

of chemical reactions that converts matter into usable energy for the cell

The Virus Question: is a virus alive?

“is butter a carb?”“…yes.”

Warm Up #2Approximately how many calories did you eat in

one day, based on the data collected in Friday’s Energy Diet Activity? Would you say this was accurate? If not, do you think you eat more or less than that a day?

Where are most of your energy (calories) coming from in your food, carbs, protein or fat?

In a particular ecosystem, the soil is very nutrient-rich at a pH of around 6.9. Acid rain caused by fossil fuel burning starts to affect the soil. How will this affect the ecosystem? Why do you think so?

Ecosystems and Food Webs

What is an Ecosystem?Ecosystem – community

of different species interacting with one another and with nonliving environment of matter and energy.

Shares same climate – long-term weather

Matter – anything that takes up space and has mass

A lake ecosystem, what is that hawk

diving for?

Ecosystem: Non-Living Factors

Abiotic Factors – non-living components of an ecosystemRocks, water, soil“A-” = not; “Bio-” =

living

Abiotic factors affecting environment:TemperatureSalinity of waterpH of soil/waterPrecipitation

Setting Ecosystem Boundaries

Ecotone – a transitional zone from one ecosystem to another

Contains mixture of species from both ecosystems

Revisiting: Riparian Zones, why are they important? Mangrove Forests –

Florida’s dying ecotone

Real Life Drama: Mangroves in Florida

Mangrove – a tree found on coastal regions of FloridaObtains freshwater from

saltwater

Estuary - partly enclosed coastal body of water with one or more rivers or streams flowing into it, and with a free connection to the open sea

Human activity = less mangroves

Effects on Loss of MangrovesRange of Tolerance –

Amount of physical and chemical change to an environment an organism can handle (Stress Zone)

Limiting Factor Principle – abiotic factor that can limit/prevent growth of species

Mangroves Salinity = amount of salt in water

Precipitation is the limiting factor in this

example. What are other limiting factors you can

think of?

Quick Quiz #2You are in a desert. Give two examples of

abiotic factors and two examples of biotic factors in a desert.

Why are estuaries, like mangrove forests, important?

We used salinity in the Mangrove Forest example. Name some other examples of limiting factors? Give an example of how one of those limiting factors can influence the tolerance of an environment.

Warm Up #6Scenario: A storm has hit a certain area of Eastern

Pennsylvania, with a large amount of rainfall. Surprisingly crops begin to die as a result. When ecologists tested the soil of the affected area, they found the pH to be more acidic than they had thought.

1.List the abiotic factors in this particular scenario?

2.What is the limiting factor in this scenario? How do you know?

3.Using the terms “tolerance” and “stress” in your answer, why were crops dying with this acid rain?

Energy Flow Within an Ecosystem

Here Comes the Sun…THE SUN

Main energy source for life on Earth (1.7 million Calories!!)

Makes energy Nuclear Fusion4 hydrogen atoms 1 helium atom + ENERGY

Other Energy Source: Chemical CompoundsFound underground/in VERY deep water

Review: PhotosynthesisProducers – make

their own energy (Autotrophs)

Photosynthesis Equation:H20 + CO2 + Light Energy

Glucose and Oxygen

Light MUST BE present

What about when NO light is present?

Chemosynthesis: Extreme CircumstancesTypically used by

remotely-located bacteria (volcanoes, hot springs)

No light present

CO2 + H20 + Sulfide Compounds + Chem Energy Carbs

CONSUMERS

Also known as Heterotrophs – obtain energy from other organisms

Types:Herbivores – Eat only plants (cows)

Carnivores – Eat only animals (dogs)

Omnivores – Eat both plants and animals (humans)

Detritivores/Decomposers - Eat dead organic matter (earthworms, fungi)

Feeding RelationshipsEnergy Flow = ONE

DIRECTION!

Different levels = Trophic Levels

Sun/Inorganic Compounds Autotrophs Heterotrophs

OR

Sun Producers Consumers

Two TypesFood Chain – A series

of steps in which organisms transfer energy by eating and being eaten

Food Web – A feeding network of complex interactions among various organismsMore Realistic!

Energy PyramidEcological

Efficiency - % of energy available at each trophic level90% of energy lost

going up trophic level!!

Biomass – Amount of living tissue within trophic level 98.8% of energy

from sun is NOT used

Should We Be Vegetarians?Herbivores =

Vegetarians

Vegetarians eat 90% more biomass than meat eaters

Grasshoppers, Humans and Frogs (Oh my!)

1 %

10 %

100% available energy

Vegetarian

Quick Quiz #3As you go up each trophic level, 90% of the

energy in the previous trophic level is lost. Where is this energy going? Is this an ecologically efficient process?

How do carnivores differ from omnivores?

Under what circumstances would an autotrophic organism use chemosynthesis rather than photosynthesis? Give an example of a location that requires chemosynthesis.

Different Diets Out ThereAtkins (emphasis on Fats/Proteins…little to no

carbs)

Okinawa (emphasis on fish, balanced diet)

Vegetarian/Vegan (no meat, can be cooked)

Cabbage Soup Diet (cabbage soup, lemon, tobasco sauce)

Raw (nothing cooked)