Chapter 1 Deck Flashcards
The Themes of Biology
What is the difference between an atom and an element?
An atom is the most basic unit of the element. An element is made up of atoms.
What are the 4 most common elements in living things?
Oxygen, Hydrogen, Nitrogen, and Carbon
What is a trace element? Give two examples and disorders caused by a lack of each element.
A trace element is needed in minute quantities. Lack of Fe(Iron) causes anemia, and lack of Iodine causes thyroid guiters.
What are Isotopes? Biological uses?
Isotopes are molecules with an unequal amount of protons to neutrons. They’re used for cancer treatment, radioactive dating fossils, and medical tracers.
Why are valence electrons important?
They determine the reactivity and the amount of bonds an atom.
How many p, n, e- does an atom of fluorine have?
P-9. N-10. E-9.
Describe the difference between polar and non-polar covalent bonds.
Polar bonds are unevenly shared and non-polar bonds are equally sharing.
What’s an ionic bond?
The transferring of electrons between 2 atoms.
What’s an ion?
A charged particle.
Name an example of one Cation and one Anion.
Ca+ and Cl-
Write a chemical equation. Label reactants, products, and where a catalyst would go.
Reactants ~(Catalyst)~ Products
What is a hydrogen bond?
A bond between hydrogen and an electronegative in another molecule.
What is a free radical?
It contains an uneven amount of electrons, and it damages membranes, proteins, and DNA.
What is an antioxidant?
Counteracts oxidation (by free radicals) in organisms.
Define the term electronegativity and give examples of the three most electronegative atoms.
The tendency to attract electrons. The most electronegative are F, O, and N.
What properties arise from water’s shape and bonding ability?
Polarity and surface tension.
Define cohesion and adhesion.
Cohesion- Water molecules bonding to each other. Adehesion- Water molecules bonding to other surfaces.
What is surface tension?
Film of water droplets on the top of water.
How do properties of water help water move up through a tree?
Adhesion lifts water up the xylem and cohesion lifts the water up.
Why is water said to act as a heat sink?
It has a high heat capacity.
How does sweating cool you off?
Sweat evaporates and leaves the surface cooler.
Why does ice float?
It’s less dense due to hydrogen bonds.
What do the terms hydrophobic and hydrophilic refer to? Which in general would refer to a polar substance and which would refer to a non-polar substance?
Hydrophobic means it doesn’t dissolve in water. Hydrophilic means it does. Hydrophilic is polar. Hydrophobic is non-polar.
What is the difference between an acid and a base?
The pH.
