Transcript NATURE OF SCIENCE

Introduction to Ecology
Objectives:
• I will be able discuss the interdependence of biotic
and abiotic factors.
• I will be able to discuss the laws of thermodynamics.
Ecology Defined
Ecology is the study
of interactions
between organisms
and their
environment.
Abiotic vs. Biotic Factors
The environment includes 2 types of factors:
1. Abiotic factors – the nonliving parts of the
environment.
Examples: water, oxygen, light, temperature, rocks,
minerals, energy
1. Biotic factors – the living parts of the
environment.
Examples: plants, animals, bacteria, fungi, and protists
The Laws of Thermodynamics
• The First Law of Thermodynamics states that energy
(or matter) cannot be created or destroyed, but can
change forms.
• The Second Law of Thermodynamics states that every
energy transfer increases the entropy (amount of
disorder or randomness) = some energy becomes
unusable.
• In biology entropy is usually referred to as heat.
• Closed systems allow energy to enter but matter
cannot enter or leave; closed systems are rare in
biology.
• Each time energy or matter “changes form” energy is
conserved but the internal energy of a closed system
changes as heat is transferred in or out of it.
Abiotic and Biotic Interactions
Levels of Organization
Arrange the following terms from the smallest to the largest:
• Population
• Cell
• Organ System
• Tissue
• Molecule
• Ecosystem
• Community
• Organism
• Organ
• Biosphere
Levels of Organization
8
Levels of Organization
• Population – a group of organisms of the same
species that live together in a certain area.
• Community – a group of populations of different
species living close enough to interact.
• Ecosystem – all living and nonliving components in
a certain area.
• Biosphere – the entire portion of the planet that
supports life.
Review Vocabulary
Habitat =
• Place where an organism lives.
• What is the habitat of a mushroom?
Niche =
• Ecological role and space that an organisms fills in the
environment (the way of life of a species).
• What is the niche of a sunflower?
MATH CONNECTION
The biomass (biological material from living or recently
living organisms) of a deciduous forest is 50% carbon.
Additionally, the biomass increases annually at a rate of
2.7 x 105 kg/hectare. Calculate the mass of carbon
accumulated and stored in 1.0 hectare of this forest in
one year. Give your answer to the nearest hundredth of
105 kg.
Note: 1 hectare = 10,000 square meters or 2.5 acres
Summary:
• In your own words, paraphrase key points of the lesson.
• Focus on the concepts you do not understand well; thinking and
writing will help you master them.
• You need to have a minimum of five sentences.
• Example of a good summary sentence: “There are biotic/living
components in environments, such as organisms, and many
abiotic/non-living components, such as water and rocks”.
• Example of a terrible summary sentence: “Today I learned about
laws of thermodynamics.” This sentence only lists the topic and
does not show what you know. Please never start with “Today I
learned about…” Instead, dive into the explanations right away.
There is no space for introductory sentences in your summary
sections of notes.