MATTER AND ENERGY TRANSFERThe atoms we are built out of

cycle through the ecosystem constantly. Describe in words or labeled drawings how each of the following atoms/molecules cycles through our ecosystems:

Pictures of each of these can be found in the book. Understand CONCEPTS don’t worry about specific chemical changes

Cycles of matter (C, N, H, O)CarbonNitrogenWaterOnce in an organism, what are

these atoms used for?◦To build new cells

Moving matter and energyHow are these atoms passed from one

organism to the next?◦When we eat a plant the atoms that make

up the plant get digested and then our body uses them to build new cells for us.

How can these atoms be returned to the non-living parts of our ecosystem? ◦When we die all our atoms are returned to

the soil through decomposition or released into the atmosphere (CO2)

Can we make new matterNO….NO…..NOWe just recycle the matter that is

here. Living things today are made of the exact same atoms that living things were made of back in dinosaur times

What about energy?The initial source of all energy is the

SUN

How is this true even for strict carnivores? ◦The sun provides energy for the plants to photosynthesize. Herbivores eat the plant and energy gets transferred to them. Then the carnivores eat the other animals and the energy is transferred to them.

The energy pyramidThe shape of the pyramid implies there

is “less” at the top. “Less” what and why is this necessary for success of the ecosystem?

Less energy and less biomass (atoms!)

WHY?: because it is the lower levels that feed and support the upper levels. Need to have more food than eaters or else you run out.

What does a food web demonstrate?

Flow of energy and matter from the producers through the apex consumers

Impact of removal of a single species:Species that depend on the removed

species (predator) for food will decline in population

Species that the removed species consumes (prey) will become over populated causing a shortage of their (the prey’s) food source.

Amt of energy passed from one trophic level to the next

10% is passed from one level to the next

What happens to the rest?◦Ultimately becomes thermal energy

(heat)

Biologically, how do we extract energy from food?

Cellular respiration: ◦Key enzymes in the cell along with

the mitochondria break the glucose down into CO2 and Water and transfer the energy to ATP molecules.

◦Other foods, like protein and fats are first converted into types of sugars that can go through the same cellular respiration process.

Diagram of PS and Respiration

Three forms of energy in an ecosystem

Light – sunChemical – glucoseThermal – body heat released

after using energy

Two purposes of food:Energy (we make ATP)Building materials

◦We use atoms and rearrange them to make cells for “us”.

◦(also specific nutrients that are used directly like vitamins, amino acids, minerals)

Why does an organism NOT disintegrate when it is alive?A constant supply of energy

keeps our body maintainedWhen we die the energy supply

ceases and body processes no longer are maintained.

Interdependence of 2 or more Organisms

Symbiosis◦Three forms

Mutualism Commensalism Parasitism

Problem 1. In an experiment, chickens were fed grain that

contained a chemical marker in its proteins. The presence of the marker can be detected in organisms. Which of the following is the most reasonable prediction from this experiment? a. The marker will only be found in the grain. b. Both chickens and wolves will have the

markerc. Wolves will have

the marker, but chickens will not.

d. The marker will only be found in the animals’ wastes.

Problem 2What two things are passed from

one organism to another in the food chain? ◦Energy and Heat◦Matter and Atoms◦Energy and Matter◦Water and food

Problem 3Which types of organisms assist

in cycling atoms back into the soil?◦Producers ◦Primary consumers◦Apex consumers◦Decomposers

Problem 4

. Which hypothesis would most likely be tested using this setup?

A. Green water plants release a gas in the presence of light.

B. Roots of water plants absorb minerals in the absence of light

C. Green plants need light for cell division. D. Plants grow best in the absence of

light.

Problem 5At position Y, carbon is most

likely to be in which of the following forms?

A. protein B. carbon solid C. carbohydrateD. carbon dioxide

Problem 6Which of the

following diagrams correctly represents an energy pyramid from this web?

B

Part C InterdependenceDefine the following terms in relationship to their

position in the hierarchy of ecosystems Populations: all of one single species that lives in a

region

Communities: all of the living things in a region (multiple species combined)

Ecosystems: All of the living things AND the non-living things they depend on

Biomes: All the ecosystems at a particular climate

Biospheres: The entire region of the planet in/on which life can exist

Food WebsExplain how each organism in a

food web can be dependent on eachother.

They can depend on each other for food, reproduction, habitat selection; no organism can survive entirely on its own.

What does the term symbiosis mean?

Relationship between two organisms that is necessary for the survival of one or both the species.

THREE TYPESMutualism – win/winCommensalism – win/no effectParasitism – win/lose

Human Impact on EnvironmentList five activities and explain HOW

◦Excessive use of fossil fuels – build up of CO2; traps extra heat; global warming

◦Over developing wooded areas – destroys habitats of organisms; impacts the food chain

◦Deforestation – removes trees which reducing oxygen production and CO2 removal

◦Excessive use of chemicals like CFC’s – depletion of the ozone layer; more harmful UV rays hitting earth

◦Pollution of lakes and rivers – damages water life; contaminates water supply

When left alone (naturally)How does an ecosystem balance

itself to keep all the organisms at the top of the food chain from wiping out all the organisms below?◦As a consumer increases the food supply of that consumer decreases; eventually there will not be enough food and the consumers will die off; As the consumers die, the food supply is rebuilt and so on

Problem 1

1.Which of the following is most likely to lead to an increase in the number of foxes over time?

A.a decrease in owls

B. an increase in hawks C. an increase in mountain lions D. a decrease in raspberry bushes

Problem 2If many trees are removed from a

forest, what is the most immediate effect on the carbon cycle in that forest?

A. increased rates of decomposition B. decreased use of atmospheric CO2

C. decreased combustion of fossil fuels D. increased production of organic compounds

Heredity and ReproductionOrganisms reproduce, develop,

and have predictable life cycles. Organisms contain genetic

information that influences their traits, and they pass this on to their offspring during reproduction.

Heredity and Reproduction1. Genes are segments of DNA molecules located in

the chromosome of each cell. DNA molecules contain information that determines a sequence of amino acids, which result in specific proteins.

2. Inserting, deleting, or substituting DNA segments can alter the genetic code

3. An altered gene may be passed on to every cell that develops from it. The resulting features may help, harm, or have little or no effect on the offspring’s success in its environment.

4. Sorting and recombination of genes in sexual reproduction result in a great variety of possible gene combinations in the offspring of any two parents

Basic InformationAccording to the central dogma of all living things: _DNA__contains the master copy of all our information.

This information is broken up into sections, or recipes,

called ___genes__.

Each gene contains the directions to make a single __protein_____ by linking together the proper sequence of _amino acids__.

Before building a protein, a temporary copy of the single recipe must be made. This copy is called __RNA_.

Ultimately it is the __protein_ that gives you the traits that we have and the __genes/DNA_ that teaches us how to make them.

DNAKept in the NUCLEUS

Wound up DNA:◦Chromosomes

MutationChange in the DNA

What problems does it cause?◦Since the DNA contains the directions to make proteins, changing the DNA could change the protein; Can cause diseases, can have no effect or can improve the function of a protein;

What types of changes are considered mutations?

Insertions – add a nucleotide; Deletions – remove a

nucleotide; Substitution – swap one

nucleotide for another

ANY CHANGE IN DNA IS A MUTATION!

Effect of a mutation on future cells

Since all the DNA is copied before cell division, a mutation in the parent cell will be copied and passed to the new cells.

Mutations do not have to be negative. They can be helpful or have no effect.

What is genetic variation and why is it important?

Genetic variation is diversity within or between species because of their DNA differences.

IMPORTANCE: It is necessary to have variation so that natural selection can occur.

Differences give individuals different ability to survive and reproduce. This allows for evolution

Three things that increase genetic variation in a populationMutation

Sexual reproduction – mixing the DNA of two individuals

Recombination/crossing over – mixing up your own DNA to make various different reproductive cell

Migration – introduction of new alleles into a population from a different population

Genetic VariationWhich process listed above also

explains how one set of parents can seemingly have an infinite number of different children?

Recombination

Problem 1Fireflies produce light inside their bodies. The enzyme

luciferase is involved in the reaction that produces the light. Scientists have isolated the luciferase gene.

A scientist inserts the luciferase gene into the DNA of cells from another organism. If these cells produce light, the scientist knows that which of the following occurred?

A. The luciferase gene mutated inside the cells. B. The luciferase gene was transcribed and

translated. C. The luciferase gene destroyed the original genes of

the cells. D. The luciferase gene moved from the nucleus to the

endoplasmic reticulum

Problem 2Which of the following best describes

the result of a mutation in an organism's DNA?

◦A. The mutation may produce a zygote. ◦B. The mutation may cause

phenotypic change. ◦C. The mutation causes damage when it

occurs. ◦D. The mutation creates entirely new

organisms.

Problem 3The diagram shows

the positions of the genes for flower color and stem length in a pea plant.

For these two genes, what is the maximum number of different allele combinations that can be formed normally in gametes produced from this cell?

A.2B.4C.6D.8

PTPtpTpt

Problem 4If the DNA is mutated which of the following

statements is true?

◦ALL other cells in the body will have the same mutation.

◦All proteins in the cell will be mutated

◦Any proteins, RNA or cells that come from the mutated DNA will have the mutation

◦The cell will fix the mutation and nothing will happen.

Problem 5Which of the following populations is likely to

have a high degree of genetic diversity? ◦ An asexual population of bacteria with a very low

mutation rate (asexual = NO VARIATION)

◦ Sexually reproducing species where crossing over is frequent

◦ A population of sheep created by cloning (NO VARIATION)

◦ A very small population of sexually reproducing species. (SMALL POPULATIONS HAVE LOW NUMBER OF VARIATIONS)

EVOLUTION AND DIVERSITYSometimes, differences between

organisms of the same kind provide advantages for surviving and reproducing in different environments.

These selective differences may lead to dramatic changes in characteristics of organisms in a population over extremely long periods of time.

KEY LEARNINGS1 New traits may result from new combinations of

existing genes or from mutations of genes in reproductive cells within a population

2. Molecular evidence (e.g., DNA, protein structures, etc.) substantiates the anatomical evidence for evolution and provides additional detail about the sequence in which various lines of descent branched

3. The principles of evolution (including natural selection and common descent) provide a scientific explanation for the history of life on Earth as evidenced in the fossil record and in the similarities that exist within the diversity of existing organisms 

Key Learnings4. Evolution occurs as a result of a combination

of the following factors:

A. Ability of a species to reproduce

B. Genetic variability of offspring due to mutation and recombination of genes

C. Finite supply of the resources required for life

D. Natural selection, due to environmental pressure, of those organisms better able to survive and leave offspring

Evolution is defined as:How a population changes

over long periods of time

What key scientist is credited with the bulk of our understanding about evolution? ◦DARWIN

Physical or molecular features used to support evolution and shared common ancestors:DNA/Protein structures (molecular) – more

similar the sequences or structure the more closely related two organisms are

Anatomy – similar body structures can provide information about relationships and ancestry

Embryonic development – the stages we go through during development can be informative

Fossils – can tell us approximately how long ago an organism lived

How does natural selection work?Requires presence of variation!Environmental stress (limited food and/or

other resources) must be presentCompetition for resources occurs - and

because they are different some are better at competing that others

Survival of the fittest – the organisms best adapted win the competition and increase their chances of surviving and reproducing

Descent with modification – winners reproduce more and the next generation consists of more individual’s with the “winner’s” traits that the “loser’s” traits.

How does genetic variation promote evolution?

Allows organisms to be on different playing fields as far as competition goes.

Increases the chances that there is a “super” trait out there than will give the organism a survival advantage

Does evolution = new species?No. EVOLUTION = a shift in

the frequency of certain alleles (variations of genes) or traits

A population does NOT have to become a separate new species (or split and become two species) in order for it to be “evolving”.

Problem 1Thousands of years ago, giraffes with short necks

were common within giraffe populations. Nearly all giraffe populations today have long necks. This difference could be due to:

 A. giraffes stretching their necks to keep their heads

out of reach of predators B. giraffes stretching their necks so they could reach

food higher in the trees C. a mutation in genetic material controlling neck

size occurring in some skin cells of a giraffe D. a mutation in genetic material controlling

neck size occurring in the reproductive cells of a giraffe.

Problem 2Scientists have concluded that snakes evolved

from an ancestor with legs. Which of the following statements provides the best evidence for this conclusion?

 A. Most species of snakes live on land. B. Snakes move extremely fast to catch their prey. C. Snakes have a well-developed backbone and

muscular system. D. Some species of snakes have limb buds

during their embryonic development ◦ The limb buds indicate that ancestors may have had

limbs

Problem 3Which of the following best explains how the fossil

record provides evidence that evolution has occurred? (need to look for an answer that talks about change over time = def of evolution)

◦ A. It indicates that forms of life existed on Earth at least 3.5 billion years ago.

◦B. It indicates the exact cause of structural and behavioral adaptations of organisms.

◦C. It shows how the embryos of many different vertebrate species are very similar.

◦D. It shows that the form and structure of groups of organisms have changed over time

Problem 4

On island chains like the one shown above, animal populations that spread from the main island to the other islands can evolve into separate species.

 CHOOSE THE STATEMENT ON THE NEXT PAGE THAT best explains what favors speciation in these situations?

Problem 4 (cont)◦A. Predators on the main island can easily

migrate to follow the populations to the other islands.

◦B. Lack of disease on the other islands enables the populations to grow and change without limit

◦C. The physical separation of the islands limits gene flow and interbreeding between the populations.

◦D. The climatic conditions of the islands allow the populations to breed all year and produce several generations

WE ARE FINISHED!

Problem 1 answers:

Problem 6