HUMANBIOLOGY_CHAPTERONE

Cell

The smallest unit of life that can function independently.

Organism

A single living individual; organisms consist of one or more cells.

Atom

A particle of matter; composed of protons, neutrons, and electrons.

Molecule

Two or more atoms joined by chemical bonds.

Organelles

A membrane-bounded structure with a specific function inside a cell.

Tissue

Group of cells that interact and provide a specific function; multicellular life only.

Organ

Two or more tissues that interact and function as an integrated unit; multicellular life only.

Organ System

Two or more physically or functionally linked organs; multicellular life only.

Population

A group of the same species of organism living in the same place and time.

Community

All populations that occupy the same region.

Ecosystem

The living and nonliving components of an area.

Biosphere

Part of Earth where life can exist.

Multicellular

Having or consisting of many cells.

Unicellular

Consisting of a single cell.

Primary Producer

Species forming the base of a food web by extracting energy and nutrients from nonliving sources; an autotroph; plants, microbes, and some bacteria.

Consumers

Organisms that eat other organisms; heterotrophs; living or dead.

Decomposers

Organisms that consume wastes and dead organic matter, returning inorganic nutrients to the ecosystem.

Homeostasis

A state of internal constancy in the presence of changing external conditions.

Asexual Reproduction

Offspring arise from only one parent.

Sexual Reproduction

The combination of genetic material from two individuals to create a third individual.

Evolution

Genetic change over time in a population.

Adaptation

Inherited trait that permits an organism to survive and reproduce.

Taxonomy

The science of describing, naming, and classifying organisms.

Scientific Method

A systematic approach to understanding the natural world based on evidence and testable hypotheses.

Hypothesis

A testable, tentative explanation based on prior knowledge.

Prediction

Anticipated outcome of the test of a hypothesis.

Observations and Questions

Initial observations and questions that lead to hypotheses and predictions.

Experimental Design

A careful plan to test a hypothesis.

Variable

Any changeable element in an experiment.

Independent variable

What is manipulated; a factor that is hypothesized to influence a dependent variable.

Dependent variable

What is measured; the response that may be under the influence of an independent variable.

Standardized variable

Held constant for all subjects.

Control

Untreated group used for comparison.

Placebo

Inert substance sometimes administered to a control group.

Sample size

Number of subjects in each treatment and control group.

Statistically significant

Unlikely to be attributed to chance; the probability that results arose purely by chance is low.

Theory

Well-supported scientific explanation.

Fact

A repeatable observation that everyone can agree on; a collection of facts by itself does not explain anything.

Technology

The practical application of scientific knowledge.

Tree of Life

Image

How many domains does the Tree of Life have?

Three domains: Bacteria, Archaea, and Eukarya.

What are Bacteria and Archaea under?

The two prokaryotic domains of life

True or False: Bacteria and Archaea are unicellular.

True

What domains lacks nuclei and other components?

Bacteria and Archaea

What are the four major kingdoms within the domain Eukarya?

Protista, Fungi, Plantae, and Animalia.

Protista

A diverse group of eukaryotic organisms, mostly unicellular, that do not fit into the other eukaryotic kingdoms.

Fungi

Eukaryotic organisms, including yeasts, molds, and mushrooms, characterized by their absorption of nutrients from their environment.

Plantae

The kingdom comprising multicellular organisms that produce their own food through photosynthesis, such as plants.

Animalia

The kingdom comprising multicellular, heterotrophic organisms that typically ingest their food, such as animals.

The scientific method

The process of science, though it varies depending on the situation, generally adheres to an organized sequence of steps.

Scientific Method Steps

1. Hypothesis

2. Experiment

3. Analysis

4. Conclusion and Reporting

Pillbugs (Rollie Poly)

omnivores, the feed on decaying matter.

How do pillbugs detect food? (smell, taste, touch, sight, sound)

smell

Pillbug: Positive Response?

movement toward a stimulus

Pillbug: Negative Response?

movement away from it

Pillbug: Defense (neither + or -)?

rolling up

choice chamber

two circular chambers with a channel in between. the first chamber has a control substance and the second chamber has a test substance.