1.
_____ is the oldest metabolic pathway and is used to degrade sugar in the absence of oxygen.: Glycolysis.
2.
All present day cells use _____ as their hereditary material.: DNA.
3.
All present-day cells use DNA as a hereditary material. Why? (6): 1. DNA based systems have advantages over RNA based systems.
2. DNA acts as a permanent repository of genetic information.
3. DNA is found principally in a double-stranded form which is more robust and stable.
4. If there is breakage, there is a repair mechanism that uses the intact strand as a template.
5. DNA templates can become more complex.
6. RNA continues to function in coding for proteins (mRNA) and catalysis (rRNA).
4.
Annelida: 1. Bilateral symmetry
2. Coelomate
3. Protostome
Ex. Segmented worms
5.
Arthropoda: 1. Segmented body
2. Jointed appendages
3. Exoskeleton
4. Bilateral symmetry
5. Coelomate
6. Protostome
Ex. Crustaceans, insects spiders
6.
Chordata: 1. Notocord
2. Nerve cord
3. Bilateral symmetry
4. Coelomate
5. Deuterostome
Ex. Lancelets, tunicates, vertebrates
7.
Cnidaria: 1. Gastrovascular cavity
2. Stinging cells
3. Radial symmetry
Ex. Hydras, jellyfish, sea anemones, corals
8.
Ctenophora: 1. Comblike jellies
2. Gastrovascular cavity
3. Radial symmetry
Ex. Comb jellies
9.
Echinodermata: 1. Bilateral symmetry
2. Coelomate
3. Deuterostome
Ex. Starfish, sea urchins
10.
Explain how prokaryotes evolved the ability to photosynthesize.: 1. Prokaryotes ate (enslaved) cyanobacteria which can make sugar from CO2 using light as an energy source.
2. A strong selective advantage would eventually be gained by organisms able to use carbon directly from the atmosphere.
11.
Explain the formation of polymers from simple organic compounds. (3): 1. Amino acids can join to form peptides.
2. Nucleotides can join to form RNA and DNA polymers
3. The need for containment is filled by amphipathic [property where one part of the molecule is hydrophobic and the other hydrophilic] molecules. (Amphipathic molecules readily form membranes. i.e. Phospholipids)
12.
How did the first prokaryotes make a living? Hint: Anaerobic fermentation. (4): 1. Glucose used for chemical energy and as a precursor for all organic molecules the cell requires
2. Glycolysis (the oldest metabolic pathway)
3. Degradation of sugar in the absence of oxygen occurs by glycolysis
4. Glycolysis is similar in all kinds of organisms (suggesting an extremely ancient origin)
13.
How were the earliest prokaryotes like present day bacteria? (5): 1. Simplest organisms
2. Spherical or rod shaped several microns long
3. Plasma membrane enclosing a single cytoplasmic compartment.
4. DNA, RNA, proteins and small molecules
5. Prokaryotes generally have no obvious internal structures
14.
In present-day cells, the amphipathic molecules used to make the cell membranes are primarily _____.: Phospholipids.
15.
Lophophorates: 1. Bilateral symmetry
2. Coelomate
3. Protostome
Ex. Bryozoans, lampshells (Brachiopods)
16.
Mollusca: 1.Foot/Visceral mass/Mantle
2. Bilateral symmetry
3. Coelomate
4. Protostome
Ex. Clams, snails squids
17.
Nematoda: 1. Unsegmented
2. No circulatory system
3. Bilateral symmetry
4. Pseudocoelomate
5. Protostome
Ex. Roundworms
18.
Platyhelminthes: 1. Dorsoventrally flattened
2. No segmentation
3. Gastrovascular cavity
4. Bilateral symmetry
5. No coelom
6. Protostome
Ex. Flatworms
19.
Porifera: 1. Colony of flagellated cells
2. Individual cells can potentially regenerate into a new individual
3. No symmetry
Ex. Sponges
20.
Rotifera: 1. Ciliated crown
2. No digestive system
3. Bilateral symmetry
4. Pseudocoelomate
5. Protostome
21.
T/F: During the first billion years on earth UV radiation was very high.: True.
22.
T/F: The earliest prokaryotes were like present day bacteria.: True.
23.
What are mitochondria? Why would prokaryotes enslave mitochondria? (5): 1. Similar to free-living prokaryotic cells
2. Resemble bacteria in size and shape
3. Contain DNA, make protein, and reproduce by dividing in two but do not have a complete genome and are dependent on the host cell
4. Without mitochondria eukaryotic cells would be anaerobic organisms
5. By engulfing mitochondria, internal oxygen concentrations are kept low
24.
What are the steps for the story of how we got the first cellular organism? (7): 1. Spontaneous or abiotically created molecules (CO2, CH4, NH3, H2, heat and electricity.)
2. Spontaneous polymerization of random polymers
3. Ribozymes
a. RNA polymers with a crucial property: the ability to catalyze reactions AND catalyze the production of copies of itself by complementary templating.
b. These became self-replicating RNA systems.
4. Family of mutually supportive catalytic RNA molecules.
a. One catalyzes the reproduction of the others.
5. Primary RNA/ protein systems.
a. Proteins with much greater catalytic capabilities that ribozymes
6. Membranes defined the first cell.
a. The development of an outer membrane was a crucial event.
7. Prokaryote cells - polypeptides (proteins) are from AA, polynucleotides (RNA and DNA)
a. Eventually, all catalysis are protein, with DNA as the main storage of genetic information.
25.
What are the steps of how we now have prokaryotes, animal eukaryotes, and plant eukaryotes?: 1. The first anaerobic bacteria
2. Atmospheric oxygen
3. Photosynthetic bacteria
4. Bacteria capable of anaerobic respiration
5. Endosymbiosis
6. Origin of eukaryotic cells with distinct organelles
7. Origin of animal eukaryotic cells
8. Origin of plant eukaryotic cells
26.
What were the conditions on Earth during the first billion years? (4): 1. No free oxygen, no ozone layer to absorb UV radiation
2. Atmosphere was comprised of CO2, CH4, NH3, and H2
3. Violent weather such as volcanic eruptions, lightning, torrential rains
4. Simple organic molecules are likely to have been produced under such conditions
27.
What were the laboratory 'created' molecules?: 1. Nucelobases
2. Sugars such as ribose
28.
When was the transition from relatively simple prokaryotic cells to larger more complex eukaryotic cells?: About 1.5 billion years ago.
