Lecture 1-5 Flashcards
Defining characteristics of life (6).
1) exhibit order/pattern
2) process energy
3) respond to environment/stimuli
4) reproduce, grow, and develop
5) regulate internal conditions
6) adapt and evolve
What are the basics of evolution by natural selection?
- individuals of a population vary in their traits
- heritable traits are passed down from parents to offspring
- a population produces more offspring than can survive
- individuals with traits best suited for the current local environment will survive and reproduce
- suitable traits will become more and more common in the population
Important statement regarding natural selection of living organisms and their various forms/functions.
Form fits function.
Name the 10 levels of biological organization (in order).
1) Biosphere
2) Ecosystem
3) Communities
4) Populations
5) Organisms
6) Organs and organ systems
7) Tissues
8) Cells
9) Organelles
10) Molecules
Why are organisms grouped from Domain to Species?
to show relatedness and similarities
Steps of hypothesis testing.
1) observation
2) hypothesis
3) prediction
4) experiment
* if result doesn’t match the original hypothesis, repeat!
Hypothesis vs theory?
hypothesis: a proposed explanation for a phenomenon
theory: a broad scope, supported by a large body of evidence that generates testable hypotheses
What are the indigenous people’s biological knowledge and how does it relate to biologists today?
1) botany for medicines and agriculture
2) zoology for hunting, fishing and aquaculture
3) ecology for interactions and interconnectedness among organisms
Biologists: observing, classifying, monitoring, etc
Describe the polarity of water.
- covalent bond (sharing electrons)
- oxygen is more electronegative than hydrogen
- asymmetrical arrangement
- oxygen has partial negative charge
- there is cohesion between other water molecules (stick together)
- hydrogen bonding between other water molecules
Why is cohesion of water important in plant biology?
- walls of plant vessels have partial charges
- water molecules are cohesive and adhere to these walls
- stick, move up, stick, move up, stick (movement of water against gravity)
Why does hydrogen bonding of water molecules create surface tension?
- water molecules have a higher attraction to each other than to air
- creates a film
- spider can walk on water
Describe the physical states of water.
liquid to ice:
- temperature decreases
- molecules slow down
- h bonding is more ordered
liquid to gas (evaporation):
- water has to absorb more heat than an equal amount of other liquids to change physical states
- high energy water molecules move away from surface
- hydrogen bonds broken
- heat required
Why does ice float on liquid water?
ice is a solid with a larger volume and is less dense
What would happen to a lake in winter if liquid water was less dense than ice?
- freeze, sink, freeze, sink until the whole lake is frozen from top to bottom
How does water act as a solvent?
- each ion is surrounded by hydration shell (cation/anion)
- forms hydration shells around large polar molecules
What adaptations of animals in cold regions have been proven to lower the freezing point of their body fluids?
by increasing their solute concentrations
Which has a lower freezing point? Seawater or freshwater and why?
seawater due to the presence of a high solute concentration that lowers the freezing point of aqueous solutions
As pH lowers, [H+] ___ and [OH] ____ .
As pH increases, [H+] ___ and [OH] ___ .
increases, decreases
decreases, increases
If there is a pH unit change of 1, how much does this increase? A 2 pH unit change?
10 fold
10^2 = 100 fold
Identify the properties of the pH scale.
0-7 is acidic
*donates a proton to solution, increasing H+ concentration of solution
7-14 is basic
*accepts a proton from solution, decreasing H+ concentration of solution
Explain the effects of acidification of biological systems.
- decrease in pH = increased [H+]
- H+ reacts with carbonate (component in shells of aquatic organisms), decreasing ability to make shells
Explain the role of buffers.
- minimize changes in concentrations of H+ and OH- in a solution
- consists of an acid-base pair that reversibly combines with H+
How does mammal blood buffering (natural buffering) work?
H2CO3 ----- (HCO3-) + (H+) -when H+ produced, pH decreases (HCO3-) + (H+) ----- H2CO3 -reaction occurs and removes excess H+ - when H+ is used, pH increases H2CO3 ----- (HCO3-) + (H+) -adds H+ back, pH is restored
Describe the hydrocarbons.
- has only carbon and hydrogen
- stored and oxidized later to release energy
