Chapter 1
*An organ, such as the liver, is composed of ______
tissues
*The digestive system is a/an ______
organ system
*The two main types of cells are _____ & ______
prokaryotes and eukaryotes
*DNA is composed of building blocks called _____
nucleotides (4 kinds; A, T, C, G, their sequences encode the info in genes)
*In eukaryotic cells DNA has the appearance of ___
a double helix (2 long strands make it up)
*The use of DNA as the information storage molecule is common to _______
both prokaryotic cells and eukaryotic cells
*Competition is central to the theory of natural selection and happens because _____
organisms typically produce too many offspring and resources are limited.
*Based on the observation that only male crickets produce a song, you hypothesize that a male’s song is a form of communication to potential mates.You set up a simple experiment to test this hypothesis. In the laboratory, you place a male snowy tree cricket in enclosure A, which is adjacent to enclosure B. In enclosure B, you place other insects, one at a time, and observe their responses to the male's song. Placing a MALE SNOWY TREE CRICKET in enclosure B is part of the _____
control group
*Based on the observation that only male crickets produce a song, you hypothesize that a male’s song is a form of communication to potential mates.You set up a simple experiment to test this hypothesis. In the laboratory, you place a male snowy tree cricket in enclosure A, which is adjacent to enclosure B. In enclosure B, you place other insects, one at a time, and observe their responses to the male's song. Placing a FEMALE SNOWY TREE CRICKET in enclosure B is part of the _____
experimental group
*Based on the observation that only male crickets produce a song, you hypothesize that a male’s song is a form of communication to potential mates.You set up a simple experiment to test this hypothesis. In the laboratory, you place a male snowy tree cricket in enclosure A, which is adjacent to enclosure B. In enclosure B, you place other insects, one at a time, and observe their responses to the male's song. Placing a FEMALE FIELD CRICKET in enclosure B is part of the _____
control group
*In order for a hypothesis to be able to be used in science, what must be true?
it is testable and falsifiable
*Explain what a scientific theory is
it generates testable hypotheses, is supported by a large body of evidence, and is broad in scope
*The universal genetic language of DNA is common to virtually all organisms on Earth, however diverse. What is the best explanation for this fact?
All living things share a common genetic language of DNA because they share a common ancestry
*Is it possible to test hypotheses without conducting experiments?
Yes, such as hypotheses involving historic events.
*A localized group of organisms that belong to the same species is called a/an ______
population
*Once labor begins in childbirth, contractions increase in intensity and frequency until delivery. The increasing labor contractions of childbirth are an example of what type of regulation?
positive feedback
*Which branch of biology is concerned with the naming and classifying of organisms?
taxonomy
*What is this an example of? Hundreds of individuals of a species have been observed and are all photosynthetic; therefore the species is photosynthetic.
Inductive reasoning
*Near universality of the genetic code provides evidence of what?
the common ancestry of all life
*What is true of natural selection?
It requires genetic variation, results in descent with modification, and involves differential reproductive success
*Is an organism that dies after 5 days of life but leaves 10 offspring, all of whom survive to reproduce, likely to be successful in an evolutionary sense?
Yes
What is EVOLUTION?
the process of change that has transformed life on earth. It is the fundamental organizing principle of biology
What is BIOLOGY?
the scientific study of life
What are the unifying themes of biology?
Organization, information, energy & matter, interactions, evolution
Define REDUCTIONISM
Reduces complex systems into simpler components
What are the levels of biological organization, from biggest to smallest?
BIOSPHERE (all life on earth), ECOSYSTEMS (all living things in a particular area, along with the nonliving components they interact with), COMMUNITIES (all organisms inhabiting a certain ecosystem), POPULATIONS (all individuals of a species in a certain area), ORGANISMS (individual living things), ORGAN/ORGAN SYSTEMS (parts of complex forms that cooperate to do a function), TISSUES (group of cells working together to perform a function), CELLS (life's fundamental unit of structure/function), ORGANELLES (functional components present in cells), and MOLECULES (chemical structure of 2 or more atoms)
Define the EMERGENT PROPERTIES
properties that arise with each step upward in the hierarchy of life, due to the arrangement and interaction of parts as complexity increases
Define SYSTEMS BIOLOGY
the exploration of a biological system by analyzing interaction among its parts (used to study life at all levels)
Actions of organisms are based on the functioning of the smartest unit of organization, called the ______
cell
Every cell is enclosed by a membrane that regulates ______
the passage of materials between the cell and its surroundings
Define PROKARYOTIC and EUKARYOTIC cells
Prokaryotic - cells of single-celled microorganisms, bacteria and archaea, no nucleus or other membrane-enclosed organelles. Eukaryotic - make up all other forms of life, contains membrane-enclosed organelles
Define DNA
deoxyribonucleic acid, genetic material within chromosomes
What happens to DNA when a cell divides?
The DNA is replicated and each cell has chromosomes identical to the parent cell
Define GENES
units of inheritance, encode info to build molecules and establish a cell's identity and function. (DNA in chromosomes, genes in DNA)
Explain GENE EXPRESSION
Nucleotides in DNA are transcribed from genes to RNA, which translates into amino acids, the building blocks of proteins.
What is mRNA?
RNA molecules translated into proteins
How does DNA ensure inheritance of genetic info from generation to generation?
By carrying instructions for making proteins and RNA, and by replicating with each cell division
Define GENOME
The entire "library" of genetic instructions that an organism inherits
Define GENOMICS and PROTEOMICS
Genomics studying whole sets of genes in 1 or more species
Proteomics - studying sets of proteins and their properties
Define PROTEOME
Entire set of proteins expressed by a cell or group of cells
Genomic and proteomic approaches have become possible through technology. List 3 important research developments that are part of this technology.
"high-throughput" technology that can analyze biological samples rapidly, bioinformatics (computational tools that store and analyze data), and the formation of interdisciplinary research teams (such as mathematicians, engineers, etc)
Define PRODUCERS and CONSUMERS
Producers - photosynthetic organisms
Consumers - organisms that feed on producers and other consumers
How are chemicals used in an ecosystem?
They are recycled through the ecosystem (ex: plant absorbs from air/soil, passed to animal that eats plant, returned to environment by decomposers, available to plant again)
What types of interactions are there among organisms?
Mutually beneficial (help both organisms) (ex; fish cleans turtle by eating parasites on turtle), sometimes both are hurt (ex: two plants compete for soil that is in short supply), sometimes one is hurt and one is helped (ex: lion eating a zebra).
Define FEEDBACK REGULATION and what types there are
When the output of a process regulates that very process. Negative feedback- output negatively regulates process. Positive feedback - end product speeds up production.
What is the core theme of biology?
Evolution - the theory that organisms living on earth today are modified descendants of common ancestors.
What is TAXONOMY?
Taxonomy names and classifies species based on similar characteristics
What is the broadest classification in taxonomy?
Domain (Bacteria, Archaea, and Eukarya)
Briefly describe the 3 domains.
Bacteria and Archaea are prokaryotic (single celled microorganisms) and Eukarya are eukaryotic (multi celled). The 3 kingdoms of multicellular eukaryotes are PLANTAE (produce own food with photosynthesis), FUNGI (absorb nutrients), and ANIMALIA (eat and digest other organisms).Single-celled eukaryotes called PROTISTS are split into several kingdoms under Eukarya.
Define "DARWINISM"
The idea of evolution that came with Charles Darwin's book "On the origin of species by means of Natural Selection" in 1859.
What were the 2 main points of Darwin's book?
Species arose from differing ancestors ("descent with modification"), and that natural selection is the mechanism of descent with modification.
Darwin developed his theory of natural selection based on what observations?
Individuals of a population vary in traits (some of which are hereditary), population can produce more offspring than can survive and reproduce, and species suit their environments.
Define NATURAL SELECTION
The best organisms survive and reproduce, the environment "selects" certain traits in the population.
What animal did Darwin study on the Galapagos Islands? What did he discover about them?
Finches - he discovered that they split up onto different islands after the volcano and adapted to their environments. On the finch "tree of life", all finches share one common finch ancestor.
Define SCIENCE
The approach to understanding the natural world (derived from a latin word that means "to know")
Define INQUIRY and the PROCESS OF INQUIRY
Inquiry - Search for information and explanations of natural phenomenon ("at the heart of science")
Process of inquiry - making observations, forming logical & testable explanations (hypotheses), and testing them. From these tests more observations occur and the process continues.
Define OBSERVATION and DATA
Observation - gathering of information
Data - recorded observations. Can be QUALITATIVE (descriptions) or QUANTITATIVE (numbers)
Define INDUCTIVE REASONING and DEDUCTIVE REASONING
Inductive reasoning - deriving generalizations from a large number of observations (big ideas coming from small ideas)
Deductive reasoning - logic flowing from a general premises to specific results. (small ideas coming from big ideas)
Define HYPOTHESIS
A tentative answer to a well-framed question
Define EXPERIMENT
A scientific test carried out under controlled conditions
Define DEDUCTIONS
predictions of results that will occur if a hypothesis is correct ("if... then" logic)
What are the two key points about the use of hypotheses in science?
The initial observations can lead to multiple hypotheses and we can never prove that a hypothesis is true, we can only support it.
Do scientists use the scientific method?
They use the general process but not in such a structured form
What is the core activity of the scientific process?
Forming and testing a hypothosis
What 3 things (other than forming and testing a hypothesis) are included in the flexible scientific process?
Exploration & discovery - inspire hypotheses, asking questions, observing nature
Community analysis and feedback - interactions within the scientific community influence which hypotheses are tested and how, provoke reinterpretations of test results, etc
Societal benefits and outcomes - societal need inspires flurry of hypotheses and studies, well-supported hypotheses affect society and inspire new scientific questions.
Define VARIABLES
factors that vary in an experiment
Define a CONTROLLED EXPERIMENT
compares an experimental group with a controlled group (the groups should only differ in one factor)
Define the INDEPENDENT VARIABLE and the DEPENDENT VARIABLE
Independent variable - the variable that is manipulated
Dependent variable - the variable that is measured
Define the CONTROL GROUP and the EXPERIMENTAL GROUP
Both groups are part of the independent variable. The control group is not changed in any way (natural), the experimental group is changed based on the one variable that is being tested.
How do scientists check one another's claims?
They repeat experiments and confirm observations
What happens if something new that relates to an old theory is discovered in science?
The old theory is revised to be accurate, or it is completely rejected
Define a MODEL ORGANISM
a species that is easy to grow in the lab and works well for questions that are being investigated.
Compare the GOAL OF SCIENCE and the GOAL OF TECHNOLOGY
The goal of science is to understand natural phenomena (discovering), the goal of technology is to apply scientific knowledge for a specific purpose (inventing).
Are science and technology interdependent?
Yes - science helps to improve technology and technological advances help to discover more in science.
What drives science and what drives technology?
Science is driven by curiosity (CAN we do it) and technology is driven by societal need (SHOULD we do it)
Explain how society is linked to science and technology
Society should be informed of how science works and of the risks & benefits of technology.
What does the scientific community reflect?
the cultural standards and behaviors of society (ex: more women are scientists now because women take a bigger part in society)