Bio 110
fossil record:
fossil record: -sedementary rocks -lakes, swamps, oceans -preserves organisms with hard shells -"gaps" in record due to a lack of organisms like bacteria found in fossils
"hard evidence"
fossils
Each water molecule is joined to _____ other water molecules by ____ bonds.
four, hydrogen
controlled burns:
get rid of underbrush but still protect trees
The bacterium Streptococcus pneumoniae is the organism responsible for bacterial pneumonia. It has a cell-wall that is predominately made of peptidoglycan and no outer membrane. Based upon these characteristics, this bacterium is __________________. It has the ability to take up DNA from its environment; this ability is known as __________________.
gram positive/ transformation
Which property of water allows dogs to cool themselves by panting?
high heat of vaporization
water:
high specific heat doesn't change temp easily
What determines the cohesiveness of water molecules?
hydrogen bonds
Some patients with Parkinson's disease have a more uncommon genotype at the ACT gene. They are homozygous for a form of that protein in which there is an alanine at position 15 rather than a threonine. This substitution results in a protein that is:
less hydrophilic
Lipoproteins
lipid combines with proteins HDL- more protein, less cholesterol LDL-less protein, more cholesterol
carbon based molecules
lipids, carbs, proteins, and nucleic acids
carbon based macromolecules
lipids, proteins, carbs, nucleic acids, Water
polypeptide
long string of amino acids
The Hawaiian Bobtail squid (Euprymna scolopes) is a small nocturnal marine invertebrate. It is best known for its light organ, which contains only one species of bacteria (Vibrio fischeri). The squid acquires these bacteria from the water shortly after hatching. These bacteria produce bioluminescence, which obscures the shape of the squid to help it avoid predators. The squid provides nutrients for the bacteria. The relationship between the squid and the bacterium is:
mutualism
Prokaryotes
no nucleus or other membrane bound orgnelles
introns:
non-coding region of DNA (found in archaea) regulatory factors, used to be called "junk"
evolution canyons:
north and south sides are very different african slope vs european slope
which monomers make up RNA?
nucleotides
Eukaryotes
nucleus, membrane bound organelles
Lipids are predominantly hydrophobic because
of their hydrocarbon chains
chemoheterotroph
organic molecules and chemical sources
photoheterotroph
organic molecules, sunlight
Which component of a water molecule is most electronegative?
oxygen is highly electronegative
amino acids are joined by:
peptide bonds
transduction
phages (virus) pass genes between bacteria
Rhodobacter sphaeroides is a purple bacteria. It usually gets its energy from sunlight and its carbon from organic molecules. If there is no sunlight, it can obtain energy from organic molecules. Therefore, this bacterium is:
photoheterotroph, chemoheterotroph
conjugation
physical connection between 2 bacteria
The unequal sharing of electrons within a water molecule makes the water molecule _____.
polar
In this molecule, what type of bond is found between the oxygen and hydrogens?
polar covalent
polymers:
polysacharides -energy storage molecules -starch, glycogen -cellulose- structure in plants -chiten-fungi and animals
The molecule in the center, surrounded by water molecules is most likely...
positively charged
which polymers are comprised of amino acids?
proteins
Which level of protein organization describes the interaction of more than one polypeptide chain to make a functional protein?
quaternary
During digestion, various enzymes are secreted into your digestive tract to break down macromolecules. This process:
requires water molecules (because hydrolysis)
saturated fats vs unsaturated fats
saturated: no double bonds, solid at room temp unsaturated: at least one double bond, liquid at room temp
best source of fossils
sedimentary rock
polypeptides
several amino acids together
functions of proteins
skin coloration digestion oxygen transport
All of the following are functions of proteins EXCEPT _____________.
storage of genetic info
smokey bear effect:
suppression of forest fires that has led to dense forests of trees and undergrowth in the southwestern United States.
where will the oldest rocks and fossils come from?
the bottom of the mountain
Animals and plants are both living, eukaryotic organisms. What is different about the ability of animals to respond to stimuli?
All of these are senses that animals have but plants do not. (light, up and down, sound)
anabolic reactions vs catabolic
Anabolic: build polymers (require energy) Catabolic: breakdown polymers (release energy)
binary fission
DNA replication (first) proteins produced cell growth (fast, every 20 minutes)
Domain System
Eukarya Archaea (closer related to eukarya then bacteria) Bacteria
You isolate a strain of bacteria and find that it obtains its carbon from carbon dioxide and its energy from complex carbon. It can be categorized as a ___________.
chemoautotroph
prokaryote morphology
coccus: round bacilli: rod spirilli:spiral
hydrophilic
water loving, strong affinity to water, Having an affinity for water
cohesion
water molecules stick to each other
adhesion
water molecules stick to other surfaces (must be wet)
radio carbon dating
-carbon half-life: 5,730 years -decays into daughter atom: 14 N -good for dating anything up to 50,000 years old -informative for recent human history
Why does ice float?
-the water molecules in ice are held further apart than the molecules in liquid water -less dense than liquid water -ice has stable hydrogen bonds (no longer forming and breaking)
You are an archaeologist who has just found an ancient fire ring containing charcoal fragments. You send these fragments to the lab for carbon-14 analysis. The report comes back that these fragments have 1/4 the amount of carbon-14, compared to modern wood. You use 5730 years as the half-life of carbon-14. You conclude the charcoal is about _____.
11,460 years old If only 1/4 of the C-14 remained (compared to modern charcoal), then this means that two half-life periods have occurred (i.e., at one half-life, 50% remains; in the second half-life, 1/2 of 50% remains=1/4) and each half-life is 5730 years. The answer is 5730 x 2 = 11,460. Be sure you could also answer this question if you were asked to date the sample if 12.5%, 50%, or 75% of C-14 remained.
how old is the universe:
13 billion years old
There are _________ amino acids that are used by organisms for protein synthesis.
20
amino acids
20 different R groups
Lipids
3 types: -dietary fats -phospholipids (make up all membranes) -steroids (all hydrophobic and not polymers)
How long ago did life show up/ evidence of organisms?
3.5 billion years ago
How old is Earth?
4.5 billion years old
Which of the following statements about the formation of polypeptides from amino acids is true?
A bond forms between the carboxyl functional group of one amino acid and the amino functional group of the other amino acid.
If two molecules of glucose (C6H12O6) are joined via condensation synthesis, the resulting molecule would have a molecular formula of _______________.
C12H22O11
The molecular formula for glucose is C6H12O6. What would be the molecular formula for a polymer made by linking three glucose molecules together by dehydration synthesis reactions?
C18H32O16
Which of the following hydrocarbons has a double bond in its carbon skeleton?
C2H4
chemoautotroph
CO2 and chemical sources
photoautotroph
CO2 and sunlight
The polar region of this phospholipid is indicated by the letter __
D
functions of cholesterol include:
It is a precursor molecule for steroidal hormones like estrogen. It is a molecule found in cell membranes. It enables the body to make Vitamin D. It is used to make the bile acids that are produced for digestion.
Which of these is not a function of cholesterol in your body?
It stores chemical bond energy that can be converted to ATP.
What was missing from the early atmosphere?
Oxygen
Primary Secondary Tertiary Quaternary
Primary: sequence of amino acids Secondary:alpha helix, hydrogen bonding, beta pleated sheets Tertiary:hydrophobic/hydrophilic interactions Quaternary:2 or more polypeptides join together to make a functional protein (ie. insulin)
The small naturally occurring fires that occurred before about 1900:
Removed undergrowth and small trees in the forest but left large trees and preserved habitat for wildlife.
A paleontologist is radiometrically dating three rocks from three different sites using the Potassium-Argon "clock", which has a half life of 1.25 billion years. The data she has obtained is shown in the table below. Based upon these data, which rock is the oldest? Rock being test Amount of parent element (Potassium) present Rock A 50% Rock B 12.5% Rock C 25%
Rock B
When water vaporizes, which bonds are broken?
The hydrogen bonds between water molecules
True or False. Bacterial conjugation is a form of sex.
True because all forms of sex, including conjugation, create a new combination of genetic material.
You are studying a sample extracted from a patient with a history of stomach ulcers and you suspect the cause is an infection due to Helicobacter pylori, a pathogenic species associated with this disorder. In this sample, you find cells with an outer membrane with lipopolysaccharides surrounding a thin layer of peptidoglycan. This species is most likely:
a gram negative bacteria
You find an ancient spear and apply dendrochronological methodology to discover that its growth ring pattern corresponds to 5,000 years ago. You are not satisfied with this single method and want to corroborate the date using another approach. You turn to carbon-14 methodology. If the dendrochronology data are correct, how much carbon-14 (compared to modern wood) should be present in the spear?
about 50%
Which property of water allows a paper towel to pick up a puddle of water?
adhesion to water molecules to other kinds of molecules
Which part of an amino acid is always acidic?
carboxyl functional group
Which of these individuals is likely to be most successful in an evolutionary sense?
an organism that dies after five days of life but leaves 10 offspring, all of whom survive to reproduce
Which of the following is not attached to the central carbon atom in an amino acid?
an oxygen
hydrophobic
avoid water, repells water
transformation
bacteria sharing genetic info by: picking up "naked " DNA from the environment
example of catabolism
breakdown of starch into simple sugars
The large diversity of shapes of biological molecules is possible because of the extensive presence of _____ in the molecules.
carbon
The Evolution Canyons found in Israel are natural laboratories for exploring evolution and adaptation because _________________________ when you compare organisms that live in both environments.
conditions on the south-facing (African) slope are much more variable than those on the north-facing (European) slope, so you expect to find organisms from the south-slope are better adapted to harsh climates
gram negative
doesn't retain dye thin peptidoglycon outer membrane lipopolysacharides virutent
absolute dating
drendrochronology, radiometric, more valuable and precise
The tendency of an atom to pull electrons toward itself is referred to as its _____.
electronegativity
evolution vs natural selection:
evolution: a change in the genetic structure of a population natural selection: differential reproduction (must be genetic variation in the population for this to occur)
You are collecting biological samples and bringing them back to the lab to determine the diversity of organisms present in the sample. Most of the species are already described, but you find one that you think is a new species. It is a prokaryote. Which of the following would you find if it is a member of the Archaea, not a bacteria?
there would be introns in some of its genes
Sweat plays an important role in thermoregulation due to the high heat of vaporization of water. That is, it takes energy to not only raise the temperature of water, but additional energy is required to make the phase change from water to gas. In individuals with HED (hypohidrotic ectodermal dysplasia), sweat gland numbers are reduced. Predictably, what symptoms occur in HED-affected individuals?
they would be prone to heat stroke
gram positive
thick peptidoglycon, retains dye
half-life
time taken to decay half of the parent element (radioactive) into a stable daughter product
dendrochronology
trees and their rings can tell the age of the tree as well as the past climate ( forrest fires, drought, hot, cold) - can go back to 9000 years
T or F Enzymes in the digestive tract catalyze hydrolysis reactions.
true
This image shows a triacylglycerol (a dietary fat). This is an example of a(n) ___________________ fat and fat comprised of only this type of molecule is expected to be _____________ at room temperature.
unsaturated: liquid
RNA's nitrogenous bases include ____________.
uracil and guanine
radiometric dating
uses radiometric isotopes that undergo radiometric activity -we know the half-life of the isotopes
The diversity of carbon compounds is largely due to carbon's ________________.
valence of 4
The change in beak size in this population of birds (seen on graphic on previous slide) happened because the birds with larger beaks:
were able to find more food. were able to raise more offspring. were able to survive through the drought. All of these are part of the process of natural selection that acted on this population.
