Scientific Method
What is the first step in the scientific method?
Observation
What is natural selection acting on - traits or individuals?
It is acting on traits in individuals, but it is populations that evolve over time.
Which four elements make up most of the human body?
Oxygen, Carbon, Hydrogen, and Nitrogen
What type of bond holds water molecules together?
Hydrogen bonds
What are the four classes of macromolecules?
Carbohydrates, Lipids, proteins, and Nucleic acids
What is the difference between an independent and dependent variable? What axis is each on?
The independent variable is manipulated (X-axis), while the dependent variable is measure (Y-axis).
What is adaptation?
A trait that improves survival or reproduction in a specific environment.
What type of bond is formed when sodium donates its valence electron to chlorine?
Ionic bond
Why does ice float on liquid water?
Ice is less dense; hydrogen bonds hold molecules apart
What type of reaction builds polymers by removing water?
Dehydration synthesis
Why must a hypothesis be falsifiable?
So it can be tested and potentially proven wrong; if it can't be tested, it is not useful in science.
What phrase did Darwin use to describe species changing over time from a common ancestor?
Descent with modification
What type of bond involves the sharing of electron pairs between atoms?
Covalent bond
What is the difference between cohesion and adhesion?
Cohesion = water to water
Adhesion = water ot other surfaces
What are the monomers of proteins called, and what type of bond links them?
Amino acids are the monomers of proteins and peptide bonds link them.
Give an example of a control group in an experiment testing plant growth under different light conditions.
A group of plants grown under normal light with no changes.
How can fossil records support the theory of evolution?
They show gradual changes in species over time and links to common ancestors.
Which property of oxygen leads to hydrogen bonding in water molecules?
High electronegativity
How does water's high specific heat help regulate coastal climates?
Oceans absorb/store heat, moderating climate
Why can humans digest starch but not cellulose?
We have enzymes that break alpha-glucose bonds (starch) but not beta glucose bonds (Cellulose).
How does scientific theory differ from a scientific hypothesis?
A hypothesis is a specific, testable explanation; a theory is a broader, well-supported by evidence, and explains many observations.
Why do Darwin's finches on the Galápagos islands have different beak shapes?
Their beaks are adaptations to different food sources.
What is an isotope, and how can isotopes be useful in medicine?
Atoms of the same element with different neutrons; used in imaging/cancer treatment.
Why is water called the "universal solvent"?
Because it dissolves polar/charged molecules
Nucleotides are the monomers of nucleic acids
The three parts are sugar, phosphate, and a nitrogenous base.