2. Define and describe science and the scientific method.

• The scientific method is a series of procedures and techniques designed to acquire reliable knowledge about how the universe and all it contains works. The principle components are observations, development of testable hypothosis, experimental design, conducting experiments and collecting data, and data analysis and write-up. Frequently it takes more than one pass through those components before new knowledge is acquired.

3. What are Newton's laws of motion? Where do they apply?

• Newton developed three "laws" of motion:
1. Objects in motion tend to remain in that state unless an external force is applied to them.
2. The relationship between an object's mass m, its acceleration a, and the applied force F is F = ma.
3. For every action there is an equal and opposite reaction, this is also known as the "seatbelt law".
• Newton's "laws" apply everywhere, from the most distant planets in the universe as they orbit their stars to the molecules that make-up proteins as they fold.

4. What is a chaotic system? Where are they found in nature?

• A chaotic system, also known as a dynamical system, is one that is extremely sensitive to the initial conditions. The classic example of a chaotic system found in nature is weather, Lorenz first discovered this in the early 1970's while developing weather simulations. His paper popularized the expression "the butterly effect".

5. List and describe as many different kinds of energy as you can.

• The two most general forms of energy are:
1. Potential, e.g. energy stored in an object on a high shelf.
2. Kinetic, e.g. energy in a car speeding down the road.
• These in-turn can be used to describe energy in many other forms:
1. Light, that is photons moving through space (kinetic).
2. Chemical, e.g. energy that is stored in coal or in a magnet (potential).

6. Explain the statement "energy always goes from more useful to less useful forms".

• This is the second law of thermodynamics. While energy is always conserved (the first law of thermodynamics) it always moves from more concentrated (more useful) to less concentrated (less useful) forms. The universe trends towards entropy, that is disorder.

7. Heat moves from place to place by either _________, __________, or _________. Fill-in the blanks and describe each of them.

1. Convection moves heat through the bulk motion of warmed materials such as water in a pot on a stove or the air above the sidewalk on a sunny day. As material closer to the heat source becomes warmer it seeks to move to a cooler place (trending towards entropy) thereby moving the heat.
2. Conduction moves heat through the collisions between atoms in an object such as a spoon in a bowl of hot soup. As the atoms in the soup become warmer they vibrate at an increased rate, causing their neighbors to vibrate more, and so on up the spoon until your hand finally burns.
3. Radiation is a form of invisible light that moves energy, for instance when you stand near a campfire and feel heat it reaches you via radiation.

8. Where do you find atoms? Where don't you find atoms? (At least in our universe.)

• Atoms are everywhere, at least on earth and in all the other matter in our universe. Dark matter and dark energy are two places in our universe that do not contain atoms.

9. Approximately what percentage of our universe is atoms today?

• About 5%. The rest is primarily dark energy and dark matter.

10. List and describe as many parts of an atom as you can.

• The nucleus, which is composed of protons and neutrons, and electrons. The nucleus holds almost all of the mass of an atom but very little of its' volume. The electrons orbit around the nucleus and "occupy" the majority of the space but very little of the mass. The number of protons in the nucleus uniquely determines what type of atom it is, e.g. carbon has 6 protons and oxygen has 8 protons. In most atoms protons and neutrons are present in roughly equal numbers.

11. What is the primary fuel consumed by nuclear fusion in stars?

• Hydrogen.

12. How do scientists think our moon was formed? About when?

• The current consensus is that it was formed about 4.5 billion years ago when an object collided with the still young earth taking itself and some of the mantle into orbit where it formed the moon.

13. Which are the terrestrial planets in our solar system? What distinguishes them from the other planets?

• Mercury, Venus, Earth and Mars. Terrestrial planets are made out of rocks and/or metals, as opposed to say Saturn, one of the gas giants, which are composed of hydrogen, helium, and the like. My very eccentric mother just served us {nori, nachos, noodles, ...}

14. Is our universe expanding, contracting, or staying the same size? How do we know?

• Expanding. By measuring what's called redshift, the amount that the wavelength of light from (very distant) objects such as supernovae is stretched as it moves through the universe to observatories such as the Hubble space telescope, scientists can measure the changing distance to those objects.

15. About how old is the universe?

• About 13.75 billion years, give or take a couple of days.

16. About how old is the earth?

17. Describe the rock cycle.

• The three main types of rocks, sedimentary, metamorphic, and igneous, are formed and re-formed by the processes beneath and on the surface of the earth. Volcanic activity, plate tetonics (principally subduction), the water cycle, and atmospheric conditions all contribute to these changes.

18. Describe the water cycle.

• Water in the oceans evaporates into the atmosphere, from the atmosphere it moves around the planet as clouds eventually condensing and returning to earth as rain or snow percipitation. On earth it is stored as snow, ice, or in the ground as liquid water, eventually making its way back to the oceans where the cycle starts again.

19. Define weather and climate.

• Weather is what we experience on a day-to-day, or short-term, basis. Climate is what the atmosphere and planet experience on a long-term basis.

20. What's an enzyme? How fast are they consumed when they do their work?

• An enzyme is an organic molecule, typically a protein, that promotes or regulates a reaction. Enzymes, and catalysts generally, are not consumed by the reactions they participate in.

21. Why is it that we are described as a "carbon based life form"?

• Carbon-carbon bonds form the basis for the molecules that make life. This carbon-carbon "chain" leaves free electrons on each carbon atom which can then be used to bond to other atoms making-up a wide variety of important biomolecules.

22. List and describe as many as the four molecules of life as you can.

• Carbohydrates, proteins, lipids and nucleic acids. Carbohydrates are energy, proteins are specially shaped tools for building things, regulating processes, etc., lipids are oily substances to build cells structures out of, and nucleic acids hold the instructions for making life.

23. List and describe as many of the parts of a cell (organelles) as you can.

• The Nucleus, DNA, mRNA, tRNA, ribosomes, mitochondria. The nucleus holds the DNA and is where mRNA is built. Ribosomes take mRNA and assemble the corresponding tRNA structures into chains of amino acids which then fold into proteins. Mitochondria provide the energy for all this.

24. What is DNA? What role does it play?

• DNA, or deoxyribonucleic acid, contains the genetic instructions which control the development and function of all (known) living things.

25. What are the different types of RNA? What roles do they play?

• mRNA, or messenger RNA, contains the instruction sequence for building one protein. It is made in the nucleus and moves to the ribosomes where it is used as "recipe". tRNA, or transfer RNA, each bind to one particular amino acid which are then used by the ribosomes to assemble the chains according to the instructions providing by the mRNA.

26. What shape does DNA take? How does it replicate itself?

• DNA is stored in a double helix, roughly like a ladder which as been held at one end while the other end is twisted. The rails of the ladder are phosphate-sugar chains, the rungs are built of nucleic acid base pairs, either A-T or G-C. DNA replicates itself by splitting in half between the base pairs and then assembling a mirror image of itself onto each half, thereby forming two copies of itself.

27. What does the expression "shape determines function" mean in the context of proteins?

• Proteins start-out as long chains of amino acids which then fold into complex shapes. The shape of a protein determines which other biomolecules it can bind to and therefore interact with.

28. What is the greenhouse effect? What is the most likely cause of it? What are the primary affects of it on the earth?

• The greenhouse effect is caused by carbon dioxide (and other so called greenhouse gases) being released into the atmosphere which in turn trap more of the heat that is radiated from the earth's surface thereby increasing the temperature on earth. The most likely cause is anthropogenic (i.e. human) activity, principally through the release of stored carbon from the burning of fossil fuels.

29. Describe the food web. Where does the energy for it come from? Where does it go? How does it move through the web?

• The sun is the principle source of energy for the food web. Plants convert that energy into carbohydrates and sugars which are then consumed by animals. Animals consume plants and/or other animals moving the energy through the food web.

30. Define, describe and compare/contrast repeatability and reproducibility in the context of science.

• Repeatabilty is the notion that a person or group can develop a prescribed set of steps which when followed will obtain the same results or data in successive trials. Reproducability is when those steps are documented and a second independent person or group can follow them to obtain the same results or data in succesive trials.