Biology Praxis II 5235
Exam 2023
taxonomy categories in order? - Answer-Domain, kingdom, phylum, class, order, family,
genus, species
Did King
... [Show More] Phillip Cry Out "For Goodness Sakes!"
human taxonomic levels? - Answer-Animalia, chordata, Mammalia, primatae,
hominidae, homo sapiens
"All cool men prefer heavy sideburns"
phases of mitosis? - Answer-Interphase, prophase metaphase, anaphase, telophase
I-PMAT
7 characteristics of all animals? - Answer-movement, reproduction, sensitivity, growth,
respiration, excretion, nutrition
MRS GREN
cation verses anion? - Answer-Cations are PAWsitive, anion stands for "a negative ion"
what do cells do in a hypotonic solution? - Answer-In a hypOtonic solution, the cell will
swell up like an "O"
when a cell is in a hypERRRRtonic solution, it shrivels and moans "ERRRRRR
OIL RIG? - Answer-Oxidation Is Loss Reduction Is Gain
What are the six stages of fertilization? - Answer-Contact, Entry, Blocks to polyspermy,
Activation of cell, restart of Mitosis, and Amphimixis
NADPH or NADP is in photosynthesis? - Answer-NADPH - P stands for photosynthesis
hypertonic solution? - Answer-high concentration of solutes in proportion to solvent
think: lots of sugar makes you hyper
which bases are pyrimidines? - Answer-Cytosine, Uracil and Thymine are PYrimidines
because you CUT a pie and are a single ring like a pie
INtrons verses EXtrons in gene expression? - Answer-Introns are "IN THE WAY" and
need to be removed; EXtrons are Expressed
what does phloem transport? - Answer-Ph stands for food - phloem transports food and
flows down from the leaves
11 human body systems? - Answer-SLIC MEN R RED
Skeletal
Lymphatic
Integumentary
Circulatory
Muscular
Endocrine
Nervous
Respiratory
Reproductive
Excretory
Digestive
mammalian vertebrate from top to bottom? - Answer-7 - 12- 5 - 1 - 1
7 cervical, 12 thoracic, 5 lumbar
and then of course, it's 1 sacrum, 1 coccyx
biological redox reactions? - Answer-oxidation is usually accompanied by a loss of
protons (hydrogen ions) and reduction is accompanied by a gain of protons
cellular respiration mnemonic? - Answer-Glycolysis slits carbs into PYs (pyruvates) to
make lemon Krapes (citric acid cycle aka krebs cycle) and lots of ATP; in the ETC,
oxygen accepts tired H+ and forms water
glycolysis summary? - Answer-Glucose splits into two molecules of a 3-C sugar (in
cytoplasm). In the process, 2 ATP, 2 pyruvic acid and 2 NADH are produced (final e'
acceptor). Glycolysis can occur with or without oxygen. In the presence of oxygen,
glycolysis is the first stage of cellular respiration. Without oxygen, glycolysis allows cells
to make small amounts of ATP. This process is called fermentation.
Krebs cycle summary? - Answer-mnemonic: Kreb kills carbs and loves lemons; and he
lives in the mitochondria matrix. Forms NADH, ATP and FADH2 and spits out CO2.
-pyruvate converted to acetyl CoA. Through a series of intermediate steps, several
compounds capable of storing "high energy" e's are produced along with 2 ATP. These
compounds, (NAD) and (FAD), are reduced in the process. These reduced forms carry
the "high energy" e's to the ETC. The Citric Acid Cycle occurs only when oxygen is
present but it doesn't use oxygen directly.
what are major molecules in Krebs cycle? - Answer-PACO = pyruvate to Acetyl CoA to
citric Acid to oxaloacetic acid
ETC of cellular respiration and role of oxygen in cellular respiration? - Answer-Electron
Transport requires oxygen directly. The ETC is a series of e' carriers in the membrane
of the mitochondria in eukaryotic cells. Through a series of reactions, the "high energy"
e's are passed to oxygen. In the process, a gradient is formed, and ultimately ATP is
produced.
-Oxygen accepts de-energized Hydrogens and forms water
Universal Blood Recipient? - Answer-AB can get Anybody's Blood
-transfusion of any blood type possible because AB blood lacks antibodies for A and B
order of white blood cells from most abundant to least abundant? - Answer-Neutrophils,
Lymphocytes, Monocytes, Eosinophils, Basophils
NEVER LET MONKEYS EAT BANANAS
Universal dONor? - Answer-type O blood is the universal dOnOr
purpose of light reactions of photosynthesis? - Answer-Make ATP and NADPH+ that will
energize the Calvin cycle (dark reactions) which is when glucose is formed from carbon
dioxide molecules
where do light reactions take place in the chloroplast? - Answer-on the thylakoid
membrane of the chloroplast
light reactions summary? - Answer-1.Light reactions occur on the membranes of
thylakoids
2.Photon absorbed by psII (P680 - chlorophyll b)
3.E excites an e' that is passed from e'-accepting molecule to molecule (ETC) until it
reaches PSI
4.The lost e' in PSII is replaced by photolysis - splitting of water into H+ and O - the H+'s
are kept inside the thylakoid and the O bonds with another O and is released as O2
5.As the e' travels down the ETC (or electron transport system) H+'s are pumped into
the thylakoid
6.Electron from PSII eventually reaches PSI (P700 - chlorophyll a) where it is excited by
another photon; the e' travels down the ETC and converts NADP+ to become NADPH
7.Also, H+ from the photolysis of water are used to generate ATP
Photolysis of water in light reactions? - Answer-2H2O --> 4 e' (replace lost ones in PSII)
+ 4H+ + 2O
Oxidation and reduction of PSII? - Answer-PSII is oxidized when it loses its e' and then
PSII is reduced when it retrieves an electron from water which returns PSII to its
unexcited state.
Relation btw ETC and Redox? - Answer-The ETC is a series of oxidation-reduction
reactions --> molecule is reduced by gaining the e' and then the molecule is quickly
oxidized by it losing the e'; the reduced molecule becomes the reducing agent for the
next molecule.
Role of plastoquinone (PQ) in the light reactions? - Answer-PQ's job is to bond with 2H+
in order to move the 2H+ ions from the stroma to the lumen inside the chloroplast. The
e' from PSII is passed to PQ and PQ bonds with the 2H+ and then this bigger molecule
diffuses through the thylakoid membrane and passes the e's to the next acceptor in the
ETC (cytochrome b6f complex); the 2H+ are released into the lumen (cavity of the
thylakoid membrane - think of thylakoid as flattened penne pasta)
So...PQ moves H+'s from the stroma into the lumen - space within the thylakoid, AKA
H+ pumping!
What molecule transfers e's from PSII to PS1? - Answer-Cytochrome b6f complex, a
pigment embedded in the thylakoid membrane, accepts the 2 e's from PQ; this occurs
after PQ releases the 2H+'s into the lumen that it pulled out of the stroma. Cytochrome
b6f complex passes the e's to plastocyanin.
What is the ONLY biological molecule capable of oxidizing water? - Answer-PSII - the
e's produced by the oxidation of water supply a steady source of e's for PSII!
What is the antenna complex of the light reactions? - Answer-The conglomeration of
pigment molecules and the "reaction center" which is where the photon is ultimately
absorbed by an e'
Role of NADP in light reactions? - Answer-NADP is the final e' acceptor in PS1 and is a
hydrogen ion acceptor - the stored E in NADPH will be used in the Calvin cycle.
Why build up H+ concentration in the lumen? - Answer-To generate ATP - the H+ pass
thru ATP synthase embedded in the thylakoid membrane which results in the
photophosphorylation of ADP
proton motive force? - Answer-build up of H+ in the lumen (created by the movement of
H+ from the stroma into the lumen by PQ) and then the movement of the H+'s thru ATP
synthase for the generation of ATP from ADP - the ATP will be used to energize the
dark reactions
How many ATP and NADPH formed in light reactions? - Answer-2 of each
Goal of the Calvin-Benson Cycle, aka dark reactions or light-INdependent reactions? -
Answer-Take the recently created NADPH and ATP and store their energy by
constructing sugars from CO2
•Where: in the stroma of the chloroplast
•Where does the CO2 come from? ◦The atmosphere - the leaf opens up its stoma and
lets CO2 in
◦When this happens, H2O is inadvertently released
phototaxis? - Answer-directional movement in response to light
summary of dark reactions (calvin cycle)? - Answer-1.CO2 is combined w/ RuBp (5C) to
form a 6C sugar via the enzyme RuBisCo.
2.6C immediately breaks down to form 2 PGA's (each 3C)
3.NADPH and ATP are used to convert PGA's into PGAL's (aka G3P)
4.PGAL's can form a 6 carbon sugar (glucose)
5.But... it takes 6 turns to generate enough carbon so that 12 molecules of PGAL are
formed 10 PGAL's are converted back to RuBP via E from ATP and 2 PGAL's combine
to make glucose
What does RuBP stand for and why is it called a CO2 acceptor? - Answer-Ribulose
biphosphate; called this because it bonds with CO2 - RuBP is carboxylated which is
catalyzed by Rubisco enzyme
Why is this called C3 carbon fixation? - Answer-Because the 1st products formed are 2,
3-C compounds (PGA)
Performed by more than 90% of angiosperms
Photorespiration is a problem
C4 carbon fixation pathway? - Answer-A 4-C compound is formed instead of a 3-C
compound; the 4-C compound is oxaloacetate. Adaptation to circumvent
photorespiration.
Plant leaf has Kranz anatomy - has bundle sheath cells which fix CO2 and have rubisco
but mesophyll cells don't so that photorespiration can be avoided.
what is Kranz anatomy? - Answer-plant leaves w/ bundle sheaf cells for photosynthesis
that avoids photorespiration
How does CO2 get to the bundle sheath cells in C4 plants? - Answer-CO2 bonds with
PEP to form OAA (oxaloacetate - a 4C compound) which converts to malate which is
shuttled to the bundle sheath cell where the CO2 is removed and used in the calvin
cycle. The remaining molecule is pyruvate which goes back to the mesophyll cell to be
converted to PEP.
Mostly in plants in hot, dry climates where C4 pathway is more efficient because CO2
has higher affinity for PEP carboxylase than rubisco at high temperatures; also corn and
sugar cane
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