Intro to Biology and Scientific Method
What are the 7 characteristics of life?
composed of one or more cells, reproduction, maintain homeostasis, respond to stimuli, grow and develop, evolve/ adapt, metabolism
Which shell of an atom has the most potential energy? Why?
The outer shell/ valence shell has the most potential energy. The shells closer to the atomic nulcleus have electrons that are more attracted to the protons in the nucleus. The outer shell has electrons that are less strongly held, so it has more potential energy and is less stable.
What is the difference between hydrophilic and hydrophobic atoms and molecules?
Hydrophobic- any substance that does not mix with water- non-polar, non-ionic
Hydrophilic- any substance that does mix with water- polar and/ or ionic
What is the difference between inductive and deductive reasoning?
Induction is making generalizations based on a large number of specific observations. It is used in descriptive or discovery science (describes natural phenomenon and occurs by observation or data analysis).
Deduction is drawing specific conclusions from general premises. It is used in hypothesis-driven or explanatory science (explaining the natural phenomenon using a general statement- hypothesis).
What is the atomic number and mass number of Na (sodium)?
How many protons, neutrons, and electrons are in Na (sodium)?
Atomic number= 11
Mass number= 23
11 protons, 12 neutrons, 11 electrons
Why is carbon highly verstatile?
It has 6 electrons in total and 4 unpaired electrons in its valence shell. This allows it to form many covalent bonds by sharing of electrons. It can act as an integration point from which a molecule can branch off in up to four directions.
Does the following hypothesis have all the features of a good hypothesis?
If bacteria are repeatedly exposed to sub-lethal doses of antibiotics, they will develop resistance over time.
What is the difference between a hypothesis and a theory?
The statement has all the features of a good hypothesis: possible explanation, based on past observation/ data, testable, can be falsified but never proven.
A theory is a hypothesis tested over and over.
What is the strongest chemical bond and what are its two types?
What are some weak chemical bonds?
Strong bond: covalent bond- polar and non-polar
Weak bonds: ionic bonds, hydrogen bonds, hydrophobic interactions, van der waals interactions
What are the four main properties of water?
cohesion and adhesion, moderation of temperature, expansion of freezing, versatility of a solvent