Populations and Ecosystems
The FOSS Populations and Ecosystems Course explores
ecosystems as the largest organizational unit of life on Earth, defined
by its physical environment and the organisms that live in the physical
environment. Students learn that every organism has a role to play in
its ecosystem and has structures and behaviors that allow it to
survive. Students raise populations of organisms to discover
population dynamics and interactions over a range of conditions. They
learn that food is the source of energy used by all life forms in all
ecosystems to conduct life processes. Reproduction, including limiting
factors, heredity and natural selection are explored as ways to
understand both the similarity and the variation within and between
species.
Web Sites
http://www.fossweb.com/modulesMS/PopulationsandEcosystems/index.html
http://www.windows.ucar.edu/tour/link=/earth/ecosystems.html&edu=elem
http://www.usoe.k12.ut.us/curr/science/sciber00/7th/classify/living/quiz/livingqu.htm
http://www.saburchill.com/questions/lanlt001.html#FOSSIL
http://www.biology.ualberta.ca/facilities/multimedia/uploads/alberta/Ecosystem.html
http://ology.amnh.org/marinebiology/workthesystem/index.html
http://www.nhptv.org/natureworks/nwepecosystems.htm
http://edugreen.teri.res.in/explore/life/ecosys.htm
http://members.tripod.com/recalde/ch5.html
Concepts
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An organism is any living thing.
An organism’s habitat is where it lives-the place where it can meet all of its
requirements for life.
A kind of organism that is different from all other kinds of organisms is called
a species.
An individual is one single organism.
A population is all the individuals of one kind (one species) in a specified area
at one time.
A community is all the interacting populations in a specified area.
An ecosystem is a system of interacting organisms and nonliving factors in a
specified area.
Biotic factors are living elements in an ecosystem; abiotic factors are
nonliving elements.
Mono Lake is an example of an alkaline lake ecosystem.
The sequence of organisms that eat one another is a food chain.
All the feeding relationships in an ecosystem define the food web for that
ecosystem.
The Mono Lake ecosystem is defined by the interactions among the organisms
and physical factors that exist in the Mono Lake Basin.
Food is energy-rich organic matter that organisms need to conduct their life
processes.
Energy in food is measured in kilocalories.
Photosynthesis is the process by which energy-rich molecules (food) are made
from water, carbon dioxide and light.
Feeding relationships define trophic levels:
producers, consumers, and
decomposers
Reproductive potential is the theoretical unlimited growth of a population over
time.
A limiting factor is any biotic or abiotic component of the ecosystem that
controls the size of a population.
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Similar ecosystems occur in areas of similar abiotic conditions on Earth
An ecosystem is a group of interacting organisms and nonliving factors in a
specified area.
All ecosystems have characteristics in common, such as trophic levels –
producers, consumers, and decomposers.
An adaptation is any trait of an organism that enhances its chances of
surviving and reproducing in its environment.
A feature is a structure, characteristic, or behavior of an organism, such as eye
color, fur pattern, or timing of migration.
A trait is the way a feature is expressed in an individual organism, such as
brown eyes, small spots, or early migration.
Variation is the range of expression of a feature within a population, such as
all the different eye colors, all the different fur patterns, and all the dates on
which migration starts.
The individuals in every population vary from one another in their traits.
Heredity is the passing of information from one generation to the next.
Chromosomes are structures that contain hereditary information and transfer it
to the next generation; they occur in nearly identical pairs in the nucleus of
every cell.
Genes are the basic units of heredity carried by chromosomes. Genes code for
features of organisms.
Alleles are variations of genes that determine traits in organisms; the two
alleles on paired chromosomes constitute a gene.
Alleles can be dominant or recessive. Dominant alleles exhibit their effect if
they are present on one chromosome; recessive alleles exhibit their effect only
when they are on both chromosomes.
An organism’s particular combination of paired alleles is its genotype; the
traits produced by those alleles result in the organism’s phenotype.
A gene composed of two identical alleles (e.g. both dominant or both
recessive) is homozygous; a gene composed of two different alleles (i.e. one
dominant and one recessive) is heterozygous.
Environmental factors put selective pressure on populations.
Natural selection is the process by which the individuals best adapted to their
environment tend to survive and pass their traits to subsequent generations.
Members of a species are all the same kind of organisms and are different
from all other kinds of organisms.
Abiotic:
Nonliving
Adaptation:
Any trait of an organism that increases its chances of surviving and
reproducing.
Alkaline lake: A salty lake where the pH is greater than 7.
Allele:
Variations of genes that determine traits in organisms; the two
corresponding alleles on two paired chromosomes constitute a gene.
Aquatic:
Of the water.
Autotroph:
Organisms that make their own food.
Biomass:
The total organic matter in an ecosystem.
Biotic:
Living organisms and products of organisms.
Carbohydrate: Food in the form of sugar or starch.
Carrying capacity: The maximum size of a population that can be supported by a given
environment.
Chromosome: A structure that transfers hereditary information to the next generation.
Community: All the interacting populations in a specified area.
Consumer:
An organism that eats other organisms.
Decomposer: An organism that consumes parts of dead organisms and transfers all the
biomass into simple chemicals.
Detritivore:
An organism that eats detritus, breaking the organic material into smaller
parts that a decomposer could use for food.
Detritus:
Small parts of organic material.
Dominant allele: A form of a gene that is expressed as the trait when a dominant allele is
present.
Ecosystem:
A system of interacting organisms and nonliving factors in a specified
area.
Environment: The surroundings of an organism including the living and nonliving
factors.
Exoskeleton: A tough, outer covering that insects and other organisms have for
protection.
Feature:
A structure, characteristic, or behavior of an organism, such as eye color,
fur pattern, or timing of migration.
Food chain:
A sequence of organisms that eat one another in an ecosystem.
Food pyramid: A kind of trophic-level diagram in the shape of a pyramid in which the
largest layer at the base is the producers with the firs-level, second-level,
and third-level consumers in the layers above.
Food web:
All the feeding relationships in an ecosystem.
Gene:
The basic unit of heredity carried by the chromosomes; code for features
or organisms.
Genotype:
An organism’s particular combination of paired alleles.
Herbivore:
An organism that eats only plants.
Heterotroph: An organism that cannot make its own food and must eat other organisms.
Heterozygous gene: A gene composed of two different alleles (a dominant and a
recessive).
Homozygous gene: A gene composed of two identical alleles (e.g., both dominant).
Incomplete metamorphosis: A process of gradual maturing of an insect (egg, nymphal
stages or instars, adult).
Individual:
One single organism
Instar:
An immature nymphal stage of an insect as it grows into an adult form.
Limiting factor: Any biotic or abiotic component of the ecosystem that controls the size
of the population.
Molting:
The process of shedding exoskeleton in order to grow.
Morph:
A form in a species that occurs in one or more forms (such as colors).
Natural selection: The process by which the individuals best adapted to their
environment tend to survive and pass their traits to subsequent
generations.
Omnivore:
A consumer that eats both plants and animals.
Organism:
A living thing.
Phenotype:
The traits produced by the genotype; the expression of the genes.
Photosynthesis: The process by which producers make energy-rich molecules (food)
from water and carbon dioxide in the presence of light.
Population:
All the individuals of one kind (one species) in a specified area at one
time.
Phytoplankton: A huge array of photosynthetic microorganisms, mostly single-celled
protests, that are free-floating in water.
Proboscis:
A tube like beak for sucking fluids from plants. True bugs have this
structure.
Producer:
An organism that is able to produce its own food through photosynthesis.
Recessive allele: A form of a gene that is expressed as the trait only when a dominant
allele is not present.
Reproductive potential: The theoretical unlimited growth of a population over time.
Species:
A kind of organism; members of a species are all the same kind of
organism and are different from all other kinds of organisms.
Terrestrial:
Of the land
Tertiary:
Third level
Trait:
The specific way a feature is expressed in an individual organism.
Trophic levels: Functional role in a feeding relationship through which energy flows.
Tufa tower:
A naturally occurring, gray, lumpy structure that forms under water in a
salt lake because of a chemical reaction between calcium and salt in the
water.
Variation:
The range of expression of a trait within a population.
Zooplankton: Microscopic adult animals and larval forms of animals found free-floating
in fresh water and seawater.
Family Activities
Fish Bowl Cake
Recipe Rating:
Prep Time: 25 min
Total Time: 4 hr 55 min
Makes: 12 servings
Nutrition Information
Kraft Kitchens Tips
Ratings and comments
You may also enjoy
1 pkg. (12 oz.) pound cake, cut into 1-inch cubes
1/2 cup jelly beans
2 cups boiling water
2 pkg. (4-serving size each) JELL-O Brand Berry Blue Flavor Gelatin
4 cups ice cubes
12 bite-size fish-shaped chewy fruit snacks
PLACE cake cubes in bottom of clean new 2-qt. plastic fish bowl; top with the jelly beans. Set
aside.
STIR boiling water into dry gelatin mixes in large bowl until completely dissolved. Add ice cubes;
stir until gelatin begins to thicken. Remove any unmelted ice. Pour thickened gelatin into fish bowl.
ARRANGE fruit snacks in gelatin to resemble fish swimming in a fish bowl. Refrigerate 4 hours or
until gelatin is set. To serve, scoop out the gelatin and cake with a large spoon. Store leftover
dessert in refrigerator.
KRAFT KITCHENS TIPS
Where to Buy a Fish Bowl
You can find a plastic fish bowl at any pet store or party store. Be sure to thoroughly wash and dry
the fish bowl before using.
Family Fun
Try using a combination of bite-size fish-, shark- and octopus-shaped chewy fruit snacks.
Easy JELL-O® Terrarium
Recipe Rating:
Prep Time: 10 min
Total Time: 55 min
Makes: 16 servings, about 2/3 cup each
Nutrition Information
Kraft Kitchens Tips
Ratings and comments
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2 cups boiling water
1 pkg. (8-serving size) or 2 pkg. (4-serving size each) JELL-O Brand Berry Blue Flavor Gelatin
2 cups cold water
16 OREO Chocolate Sandwich Cookies, finely crushed
44 NILLA Wafers, crushed
16 NUTTER BUTTER Peanut Butter Sandwich Cookies, coarsely crushed
2 cups thawed COOL WHIP Whipped Topping
STIR boiling water into dry gelatin in large bowl at least 2 min. until completely dissolved. Stir in
cold water. Pour into large glass bowl.
REFRIGERATE 45 min. or until set.
TOP gelatin with a layer each of crushed OREO Cookies, NILLA Wafers and NUTTER BUTTER
Cookies to resemble a terrarium. Top with whipped topping for "snow."
Aquarium Cups
Recipe Rating:
Prep Time: 15 min
Total Time: 1 hr 15 min
Makes: 4 servings, about 1/2 cup each
Nutrition Information
Kraft Kitchens Tips
Ratings and comments
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3/4 cup boiling water
1 pkg. (4-serving size) JELL-O Brand Berry Blue Flavor Gelatin
Ice cubes
1/2 cup cold water
1/2 cup chopped strawberries
4 bite-size fish-shaped chewy fruit snacks
STIR boiling water into gelatin in medium bowl at least 2 minutes until completely dissolved. Add
enough ice cubes to cold water to measure 1-1/4 cups. Add to gelatin; stir until slightly thickened.
Remove any unmelted ice. If mixture is still thin, refrigerate until slightly thickened.
PLACE fruit on bottom of 4 clear plastic cups. Pour thickened gelatin evenly over fruit. Suspend
fruit snacks in gelatin.
REFRIGERATE about 1 hour or until firm.
KRAFT KITCHENS TIPS
Great Substitute
Substitute your favorite fruit for the strawberries.
Under-the-Sea Cake
Recipe Rating:
Prep Time: 35 min
Total Time: 5 hr 35 min
Makes: 16 servings
Nutrition Information
Kraft Kitchens Tips
Ratings and comments
You may also enjoy
1 pkg. (2-layer size) white cake mix, any flavor
2 cups thawed COOL WHIP Whipped Topping, divided
3/4 cup boiling water
1 pkg. (4-serving size) JELL-O Brand Berry Blue Flavor Gelatin
2 cups ice cubes
10 NILLA Wafers, crushed
2 chewy fruit snack rolls
15 jelly beans
4 TEDDY GRAHAMS Honey Graham Snacks
Decorating gel
7 bite-size fish-shaped chewy fruit snacks
PREPARE and bake cake batter in greased foil-lined 13x9-inch baking pan as directed on package.
Cool completely. Invert cake onto large platter; remove pan and foil. Use a serrated knife to cut
1/2-inch-wide strip off each side of cake. Cut each strip in half lengthwise; set aside.
SPREAD cake with 1-1/2 cups of the whipped topping. Stack cake strips around outside edges of
cake to make a rim. Spread rim with remaining 1/2 cup whipped topping. Refrigerate until ready to
use.
STIR boiling water into dry gelatin mix in large bowl at least 2 min. until completely dissolved. Add
ice cubes; stir until gelatin begins to thicken. Remove any unmelted ice. Pour thickened gelatin
into center of cake as shown in photo. Refrigerate 4 hours or until gelatin is set. Decorate with
remaining ingredients to resemble an aquarium. Store in refrigerator.