Wk1 Lectures 1+2 Ch 1.1, 1.6, 1.2, 1.3, 1.4, 1.5, 7.1, 7.2, 2.2, 2.5 Flashcards
What is an organism?
A life form, something that’s alive and made of one or more cells.
What are the 5 characteristics of life?
- Cells/Organization
2.Reproduction/Replication - Information
- Energy Use/Metabolism
- Biological Evolution
What is a theory?
A broad explanation of some aspect of the natural world supported by a LARGE BODY OF EVIDENCE - extremely likely to be true, but can never be proved true
What are the 3 unifying ideas of biology?
- The Cell Theory
- The Chromosome Theory of Inheritance
- The Theory of Evolution
What question does the cell theory address?
What are organisms made of, and where do they come from?
What question does the chromosome theory of inheritance address?
How is hereditary information transmitted from one generation to the next?
What question does the theory of evolution address?
How are organisms related to one another?
Who is Robert Hooke and what did he discover?
A microscopist that discovered cells using a 30x microscope.
Who is Antony van Leeuwenhoek?
A Dutch scientist that developed more powerful microscopes (300x). Discovered animalcules (microorganisms) by using his own teeth samples before/after drinking hot coffee.
What are cells?
The basic structural and functional unit of all organisms. A highly organized (plasma) membrane bound compartment It also contains concentrated chemicals in an aqueous solution.
What is the cell theory?
All organisms are made of cells, and all cells come from preexisting cells.
What is a hypothesis?
A TESTABLE statement that explains something observed. Used when referring to explanations for more tightly focused questions.
What is an experiment?
Allows researchers to test the effect of a factor on a particular phenomenon.
What is a prediction?
A measurable or observable result that must be correct if a hypothesis is valid.
What was Louis Pasteur’s hypothesis?
Cells arise from cells, and that cells do not arise by spontaneous generation
What were Louis Pasteur’s experiments to test his hypothesis? What were the results?
Two flasks were used that differed in stem shape: straight and swan necked. Both flasks had broth and were boiled for identical times to kill organisms. After sterilization, only microorganisms were found in the straight necked flask, which corroborated the all-cells-from-cells hypothesis.
Where did the first cells come from?
Chemical evolution
What 2 claims did Charles Darwin and Alfred Russel Wallace make regarding the natural world?
- All species (a distinct organism) are related by common ancestry.
- Characteristics of species can be modified from generation to generation (variation/diversity)
What is evolution?
A change in the characteristics of a population over time => species are related to one another and can change through time
What is a population?
A group of individuals of the SAME species, living in the SAME area, at the SAME time.
What does natural selection explain?
Natural selection
is a process that explains how evolution occurs.
What two conditions must be met for natural selection to occur?
- Individuals within a population must vary in characteristics that are heritable–can be passed on
- In a particular environment, certain versions of these heritable traits help individuals survive better and reproduce more than other versions.
What happens if certain heritable traits lead to increased success in producing offspring?
These traits become more common in the population over time.
What does natural selection act on?
Individuals
What does evolutionary occur in?
Populations
When does speciation occur?
When populations diverge to form new species.
What is the theory of evolution?
All species are related and gradually change over time
What do cell theory and theory of evolution by natural selection imply?
- All species come from preexisting species
- All species trace their ancestry back to a single common ancestor (LUCA)
What does L.U.C.A stand for?
Life’s Universal Common Ancestor
What is fitness?
An individual’s ability to reproduce compared to others in the population. Individuals with high fitness produce many surviving offspring.
What is an adaptation?
Any heritable trait that increases the fitness of an individual in a particular environment relative to individuals lacking that trait.
What is the tree of life?
A family tree of organisms [that describes the genealogical relationships among species with a single ancestral species at its base.]