1. How can we account for life’s dual nature of unity and diversity?
All forms of life have common unifying features yet are amazingly diverse. Both of these facts are a result of our DNA.
All life has commonalities, while still being unique. For example insects all have a hard exoskeleton and numerous legs, but they all have different rolls to play on earth, as well as different shapes and sizes. Another good example is humans. We're all built with the same general composition, but each of us are unique within those boundaries.
2. While waiting at an airport, Neil Campbell once overheard this claim: "It's paranoid and ignorant to worry about industry or agriculture contaminating the ...view middle of the document...
This non-covalent bond is known as a hydrogen bond. Water is strongly cohesive because each molecule may make four hydrogen bonds with other water molecules in a tetrahedral configuration. Surface tension is a result of the cohesion of water molecules at the surface of a body of water. The ability of some insects to float on water is accounted for because of this property. Conversely, the adhesive property of water (water bonding to a molecule other than water) allows for capillary action to occur such as trees transporting water from the ground to the topmost branches.
Adhesive: water molecules are attracted to other materials. For example, if you place a capillary glass tube open ended into a container with water, you will observe a concave up curve as a result of water molecules attracted to the polar glass capillary tube.
Cohesive: water molecules are attracted to other water molecules. For example, if you place a capillary glass tube open ended into a container with mercury, you will observe a concave down curve because the glass is polar which doesn’t attract with mercury. As shown in the figured.
Ability to Modern Temperature
Water's Absorption of Heat
Water is able to resist temperature changes due to hydrogen bonding. Specifically, in order for water to increase in temperature hydrogen bonds must break giving rise to the relatively high boiling point of water. Conversely, hydrogen bonds must form before the temperature of water may be lowered. This property allows Earth's bodies of water to maintain temperatures by storing heat from the sun and releasing heat when cooler conditions arise.
High Specific Heat
Water has a high specific heat (the measure of heat energy required to increase the temperature of a unit quantity of a substance by unit degree) of 4.1813J/(g·K) and a high heat of vaporization (heat energy required to evaporate one unit quantity of a substance) of 40.65 kJ·mol−1. The consequence of this is that water is an excellent temperature regulator, being able to absorb and store a significant amount of heat before increasing in temperature and thus accommodate for environmental temperature changes and those caused by exothermic reactions within the body.
During the evaporation of water, fast-moving water molecules constantly collide and eventually escape from the surface. These escaping molecules carry heat along with their escape, causing the slower moving water molecules left behind to cool. Sweating is an example of this property, as the water molecules in sweat absorb the heat from the body and move faster, allowing them to vaporize.
Commonly describes as the "versatile solvent", water is a substance that can dissolve almost anything. Because of this, water in nature and in use is rarely pure, and may have some properties different from those in the laboratory. Salts such as sodium chloride dissolve in water by dissociating as each ion becomes surrounded (spherical...