Biology: The Science of Life (Ch 1)
How do organisms maintain homeostasis?
By keeping the concentrations of most metabolites at steady state; it is maintained by chemical messengers called hormones (feedback loops)
What happens if homeostasis is not maintained?
Cells lose the ability to carry out normal functions; failure to maintain it leads to: diseased state or death
Three critical factors of the classification of organisms: 2. Cellular structure: What is a *eukaryotic" cell?
a multicellular organism which contains organelles and nuclei
What is a hypothesis?
a possible explanation for a natural event; based on existing knowledge, so it is more informed than a guess
What is a placebo?
a treatment that contains no medication but appears to be the same treatment as that administered to the test groups in a controlled study
How are living things organized?
all living things share basic levels of biological organization
the levels of organization: interacting populations in a particular area
community
Three critical factors of the classification of organisms: 1. Number of cells: What does it mean to be *multicellular*?
containing many types of cells
Three critical factors of the classification of organisms: 1. Number of cells: What does it mean to be *unicellular*?
containing one type of cell
Classification of living things: all living organisms are classified into three major groups called ___________.
domains
the levels of organization: community plus the physical environment
ecosystem
Which of the following partial sequences represents the hierarchy of biological organization from the most to the least complex level?
ecosystem, community, population, organism, cell, organelle
How can the *similarities* between organisms as well as *diversity* be explained?
evolutionary theory (natural selection)
definition: the maintenance of constant internal conditions despite external fluctuations
homeostasis
Which of the following factors is not critical for classifying an organism into one of the three domains?
how it responds to stimuli
Which of the following is true about the scientific method?
hypothesis is an educated guess as to the solution to a scientific dilemma
Science has ___________ the ____________ of life.
improved; quality
Three critical factors of the classification of organisms: 3. How food is obtained: What are the three ways?
ingested, made, absorbed
Researchers testing new drugs usually give the drug to one group of people and give placebos, "sugar pills," to another group. The group receiving the placebo:
is the control group
Three critical factors of the classification of organisms: 2. Cellular structure: What is a *prokaryotic" cell?
it is a unicellular organism that lacks organelles and nuclei (space is limited)
Biology is the study of ______?
life
What is the definition of randomized?
make unpredictable, unsystematic, or random in order or arrangement; employ random selection or sampling in
What are the four kingdoms of Eukarya?
protists (only unicellular), fungi, plants, animals
ability to understand and reason with basic scientific concepts; communicate those thoughts to others; integrate them Ito your decision making
scientific literacy
Overview of Domains: 1. Eukarya: size, number of cells, complexity, food
size: relatively large number of cells: both unicellular and multicellular complexity: eukaryotic food: both absorbed, ingested, and made
Overview of Domains: 1. Bacteria: size, number of cells, complexity, food
size: relatively small number of cells: unicellular complexity: prokaryotic food: ingest
Overview of Domains: 1. Archaea: size, number of cells, complexity, food
size: relatively small number of cells: unicellular complexity: prokaryotic food: absorbed (similar to bacteria but can be found in unique areas: can grow in extreme conditions)
the levels of organization: A group of similar, interbreeding organisms
species
what is a experimental variable?
the factor in a experiment that is being changed (independent)
What is a control group?
the group in an experiment or study that does not receive treatment; used as a benchmark or standard to measure how the other tested subjects do.
What is are *Cells*?
the smallest, most basic unit of life (although it is alive, it is made from nonliving organisms)
Science is....
the use of evidence to construct testable explanations and predictions of natural phenomena, as well as the knowledge generated through this process
What is a responding variable?
the variable that is observed and that changes in response to the manipulated variable (dependent)
Which of the following theories best explains the similarities as well as diversity amongst living organisms?
theory of evolution
the levels of organization: a group of cells with a common structure or function
tissues
Domain: What are the three groups:
1. Bacteria 2. Archaea 3. Eukarya
What are the levels of organization? (broadest to specific)
1. Biosphere 2. Ecosystem 3. Community 4. Population 5. Species 6.Organism 7. organ systems 8. organ 9. tissues 10. cells 11. molecules 12. atoms
What are the 3 misleading evidence which obscures the truth?
1. Pseudoscience (individuals make scientific sounding claims that are not supported by trustworthy, methodical scientific studies) 2. Anecdotal observations (based on only one or a few observations, people conclude that there is or not a link between two things) 3. superstitions
If there is so much diversity between living organisms, what do they have in common? *similarities despite diversity*
1. all organisms are made of cells 2. all cells have similar molecules 3. all cells do similar chemical reactions 4. all cells use the same genetic material (DNA)
What are the characteristics of living things? (6)
1. levels of organization 2. the ability to acquire materials 3. ability to maintain an internal environment (homeostasis) 4. ability to reproduce to stimuli 5. ability to reproduce and develop 6. ability to adapt and evolve to changing conditions
The classification of given organisms are based on what three critical factors?
1. number of cells 2. cellular structure (complexity of cells) 3. how food is obtained (ingested, made, absorbed)
What are the steps to the Scientific Method?
1. observation 2. hypothesis 3. Prediction 4. experiment 5. conclusion
You are classifying an organism and trying to determine to which domain it belongs. The organism absorbs its food, is unicellular and was collected from a person suffering from an infection. This organism probably belongs in the domain......
Bacteria
Viruses are not considered living organisms; do not contain cells; do not fit in any of the domains (cannot produce without invading cell)
How do viruses fit into this classification scheme?
Why is the maintenance of homeostasis important to all organisms?
It needs to be maintained in order to keep the body functioning
Limitations of Science
Science does not: 1. make moral judgements 2. make aesthetic judgements 3. tell you how to use scientific knowledge 4. draw conclusions about supernatural explanations
What are scientific theories?
System of ideas that explain many related observations and is supported by a large body of evidence acquired during scientific investigation (ACCEPTED EXPLANATIONS FOR HOW THE WORLD WORKS)
Which of the following is not a characteristic of all living things?
They are composed of at least two cells
What is the placebo effect?
a beneficial effect, produced by a placebo drug or treatment, that cannot be attributed to the properties of the placebo itself, and must therefore be due to the patient's belief in that treatment.
What is an observation?
a formal way of watching the natural world
What is a double-blind study?
When neither the patient nor the technician is aware of the specific treatment
Why is it important that an experiment include a control group?
Without a control group, there is no basis for knowing if a particular result is due to the variable being tested or to some other factor.
what is an *organism*?
a individual; complex individuals containing organ systems who exhibit properties of life
A population differs from an ecosystem because.....
an ecosystem contains a community; a population does not
the levels of organization: smallest unit of element
atom
What are the levels of biological organization? (specific to broad)
atoms, molecules, organelles, cells, tissue, organs, organism, population, community, ecosystem, biosphere
the levels of organization: Regions of Earth's crust, waters, and atmosphere inhabited by living organisms
biosphere
What are some human examples of conditions maintained by homeostasis?
blood sugar, pH of blood, temperature regulation, sweating when hot
levels of organization: the structural and functional unit of all living organisms
cells
the levels of organization: union of two+ atoms of the same or different elements
molecules
the levels of organization: composed of tissues functioning together for a specific task
organ
the levels of organization: composed of several organs working together
organ system
the levels of organization: complex individuals who contain organ systems
organisms
The people within one room compose a.....
population
the levels of organization: organisms of the same species in a specific area
population