B/B Uworld MCAT

pKa amino acid group is ratio of protonated to deprotonated species is 1:1 usually. W A decrease in pH yields: A increase in pH yields:

Decrease pH: increased H+ conc (favors protonation) Increase pH: decreased H+ conc (favors deprotonation).

Reduced ventricular filling would lead to LESS blood being expelled from the ventricle with each contraction and ______ CO.

Decreased

Increase Ventricular filling -> Increased Stroke volume -> Increase cardiac input -> _____ Vascular Resistance

Decreased *Same for reversed

Infertility in patients with endometriosis can result from ectopic endometrial tissue deposits in:

canal, ovaries, fallopian tubes (not urethra)

What happens after you eat?

in an energy-rich state (eg, after a meal), leptin is released by white adipocytes to trigger appetite suppression via the hypothalamus. In contrast, in an energy-poor state, ghrelin is released by stomach gastric cells to trigger hunger and food-seeking behavior via the hypothalamus.

Polar and charged amino acid are in the outside or inside layer when in water?

inside later (or else it will preferentially bind to water through H-bonding and DESTABILIZE the complex)

divergent evolution

when two or more species sharing a COMMON ANCESTOR become more different over time

Is π bond or σ bond portion of the C=S bond stronger or weaker?

σ are lower in energy, more stable and have greater dissociation -Double bond: one σ bond, one π bond, -Triple bond: one σ bond, two π bonds.

Concentrations of CO2, HCO3- and pH: in Oxygen-rich and Oxygen-poor blood

(RED) Oxygen-rich blood: LOW CO2, LOW HCO3, HIGH pH (BLUE) Oxygen-poor blood: HIGH CO2, HIGH HCO3, LOW pH

Complete removal of the ovaries would most likely result in:

-Irritability, anxiety, fatigue -Breast atrophy (breast shrink) -Infertility -Decreased Bone Mass

vasoconstriction

-decrease blood flow -decrease diameter of superficial blood vessels. -increase blood flow

Saltwater fish osmoregulation

-fish has to constantly drink water because they keep losing more water to their surroundings; their urine is concentrated with ions *Lose H2O, Gain Na+

vasodilation

-increase blood flow -increase diameter of superficial blood vessels. -decrease blood flow

Juxtamedullary nephrons have ___ loops of Henle extending deep into the salty medulla to ____ water reabsorption *Cortical nephrons have ___ loops of Henle extending shorter distances into the medulla, making them ___ efficient at water reabsorption.

-long, maximize -shorter, less *Camels absorb more water in water-deficient environments -> camels have higher # of juxtamedullary nephrons & lower # of cortical nephrons

If cldnk mRNA is found in the same cells as the mRNA, then cldnk must be expressed in oligodendrocytes. *if probe that is complementary to cldnk mRNA hybridizes to cells that also express plp1A, then cldnk is expressed in oligodendrocytes.

...

When acetylcholine (ACh) is released by the motor neuron at the neuromuscular junction:

1) ACh binds and opens ligand-gated ion channels in the sarcolemma (the plasma membrane of the muscle cell) 2) Na+ flows down its electrochemical gradient and into the cell through the channel, resulting in depolarization of the sarcolemma and generation of an action potential that propagates along the muscle fiber in all directions. 3) At certain locations along the muscle fiber, the sarcolemma burrows deep into the cells, forming a channel known as the transverse (T) tubule, which brings depolarizing current close to the sarcoplasmic reticulum (SR) (Choice B). The SR is a specialized smooth endoplasmic reticulum responsible for regulating cytosolic Ca2+ levels within the muscle cell. 4) Action potential propagation through the T tubule ultimately leads to the opening of Ca2+ channels in the SR membrane. Because Ca2+ is more highly concentrated inside the SR than in the cytosol, the opening of these channels results in Ca2+ flowing down its concentration gradient and into the cytosol. 5) Cytosolic Ca2+ ions then bind to troponin, which allows the actin and myosin filaments of the sarcomere to slide across one another. The sliding of the filaments results in shortening of the sarcomere and overall muscle contraction 6) The Ca2+ channels in the SR membrane close when the depolarizing stimulus ceases. Active transport Ca2+ pumps sequester the Ca2+ back into the SR, which allows the muscle to return to its relaxed state as cytosolic Ca2+ concentration falls

Ligand-gated ion channel steps:

1. APs reach axon terminals 2. Ca2+ channels open 3. Ca2+ ions enter the cell 4. Ca2+ triggers NT release by exocytosis 5. NT binds ligand-gated ion channels to allow ion to flow through 6. Inhibitory or excitatory cell response

lytic cycle

1. Attachment: bacteriophage attaches to bacterial cell wall 2. Viral genome entry: inject its genome into the cytoplasm of the bacterial host 3. Host genome degradation: Viral enzymes degrade the host genome into nucleotide components to provide the building blocks for replication of the viral genome 4. Synthesis: Loss of the bacterial chromosome ends synthesis of host molecules. *As a result, the host machinery (eg, ribosomes), now under the control of the viral genome, begins to synthesize the components needed for new viral progeny, which then assemble inside the host cell. 5. Release: Many newly assembled viral progeny (virions) are released as the bacterium disintegrates (lysis) due to the action of lysozymes on the host cell wall.

Hormones secreted by the adrenal gland regulate energy metabolism as follows:

1. Glucocorticoids (eg, cortisol) released by the adrenal cortex act on the liver to stimulate the synthesis of glucose from other molecules (ie, gluconeogenesis) and the breakdown of fats into fatty acids (ie, lipolysis). Both glucose and free fatty acids are forms of cellular energy that can be readily utilized. 2. Norepinephrine and epinephrine are released by the adrenal medulla to modulate the metabolism of glycogen, the storage form of glucose. Both hormones promote breakdown of glycogen into glucose monomers in a process known as glycogenolysis. By inhibiting the enzymes that mediate glycogen synthesis, norepinephrine and epinephrine also inhibit glycogenesis (the formation of glycogen from glucose).

What is the size of the pSKII plasmid after it is digested by EcoRI and XhoI and the cldnk gene is inserted? *Given: pSKII= 2958 bp; ECORI -> Xhol= 32 bp; cldnk= 915bp

2958 (pSKII) plasmid− 32 (Xhol) digested + 915 (cldnK) inserted = 3841 bp

1 amino acid

110 Da

Size of one amino acid

110 Da

What occurs during bone remodeling?

1. osteoclasts break down (resorb) old bone and osteoblasts deposit new bone. 2. osteoblasts promote the precipitation of Ca and PO4 from the bloodstream and transfer --> incorporation into the bone matrix.

A student adds 5 bacterial cells to a test tube containing fresh medium and incubates it for 3 hours at 37°C. If the bacterial population shows an initial lag phase of 20 minutes followed by a doubling time of 40 minutes, what is the approximate number of bacterial cells present at the end of the incubation period? (Note: Assume unrestricted growth during incubation.) A.20 cells B.40 cells C.80 cells D.160 cells

2^n (n=generations) Calculate time in log phase: 180 min incubation time (aka 3 hours) − 20 min lag phase = 160 min log phase # of generations in log phase period: 160 min log phase / 40 min generation time = 4 generations final population size = bacterial cells * 2^n 5 bac cells * 2^4 = 80 cells

alpha decay

4/2 He

cortical nephrons

85% of all nephrons short nephron loops efferent arterioles branch into peritubular capillaries around PCT and DCT

Genetic Drift

A change in the allele frequency of a population as a result of chance events rather than natural selection. **Genetic drift is a mechanism of evolution; however, unlike natural selection, the variations in allele frequencies occur randomly by chance. Because smaller populations have a smaller gene pool, the random (good or bad) variations due to genetic drift cannot be buffered.

Determine sugar conformation?

Look at highest number of chiral carbons (can be C6 of the ring) R-stereochemistry= D-sugar

myelin sheath

A layer of fatty tissue segmentally encasing the fibers of many neurons; enables vastly greater transmission speed of neural impulses as the impulse hops from one node to the next.

RNA dependent RNA polymerase

A viral enzyme that makes a strand of RNA by reading a strand of RNa . All prokaryotic and eukaryotic RNa polymerases are DNa dependent; they make a strand of RNa by reading a strand of DNA.

A subset of aggressive cancers has a relatively high growth rate, leading to the formation of large tumors. An effective drug against fast-growing tumors would most likely NOT target which stage of the cell cycle? A.G0 B.G2 C.G2/M checkpoint D.G1/S checkpoint

A. G0 (during resting phase)

A drug that blocks the release of adrenocorticotropic hormone from the anterior pituitary would most likely: A.decrease secretion of cortisol from the adrenal cortex. B.decrease secretion of thyroid-stimulating hormone from the anterior pituitary. C.increase secretion of oxytocin from the posterior pituitary. D.increase secretion of calcitonin from the thyroid.

A.decrease secretion of cortisol from the adrenal cortex.

Stenosis is the abnormal narrowing of a tubular structure in the body, such as a blood vessel. Stenosis of the afferent arterioles in the kidney would be expected to: A.decrease the glomerular filtration rate. B.increase blood flow to the glomeruli. C.decrease resistance in the afferent arterioles. D.increase output of urine.

A.decrease the glomerular filtration rate. *stenosis of the afferent arteriole would limit the amount of blood reaching the glomerulus, leading to decreased glomerular hydrostatic pressure and, consequently, a decreased GFR.

Hormones secreted by the adrenal medulla most likely influence energy metabolism by: A.inhibiting proteins that mediate glycogen synthesis. B.activating their cytosolic receptors in target cells. C.reducing the activity of enzymes that catalyze fat hydrolysis. D.increasing the activity of proteins that inhibit gluconeogenesis.

A.inhibiting proteins that mediate glycogen synthesis. *During periods of stress, hormones secreted by the adrenal gland influence energy metabolism by promoting energy utilization and inhibiting energy storage.

Post-excercise replenish body by:

ATP, creatine phosphate, glycogen stores and restocking myoglobin with O2

adaptive radiation

An evolutionary pattern in which many species evolve from a single ancestral species *process of diversifying characteristics in a subgroup of individuals from a single species.

Apoptosis and the results of ROS in the cell

Apoptosis caused by certain developmental events, DNA damage, and reactive oxygen species. Its induced when cytoC leaves mito and enters cytosol -> activates caspase. Caspase in turn activates several degradative pathways such as proteolysis.

If gel placed with low-pH end near the anode (attracts anions) and the high-pH end near the cathode (attracts cations). When are the protons protonated and how do they move?

At low pH, proteins are fully protonated, making them (+) charged ->causing them to migrate anode -> cathode. Proteins start at high-pH end are initially deprotonated and (-) charged, so they migrate toward the anode.

A kinetics experiment reveals that the enzyme fumarase catalyzes the dehydration of malate with a kcat of 900 s−1. If the substrate concentration is equal to the Km of the reaction, what is the reaction velocity when the enzyme concentration is 200 nM? A.3.6 × 102 µM/s B.9.0 × 101 µM/s C.4.5 × 10−3 µM/s D.2.2 × 10−4 µM/s

B. 9.0 × 101 µM/s M-M equation: V0=kcat[E][S] / Km+[S] if Kcat & E = Vmax V0= Vmax[S]/ K[S] subbing Km in leads to: V0= Vmax/2 Vmax= 900 s-1 * 200 nM = 180 uM/s V0 = 180 uM/s / 2 V0= 9x101 uM/s

Gene copy number is proportional to protein expression for pyruvate kinase. If this hypothesis is correct, which kinetic parameter would be expected to double when the gene copy number doubles? A.Catalytic efficiency B.Maximum velocity C.Catalytic turnover D.Equilibrium constant

B.Maximum velocity Vmax = kcat × [Etot]. *increase in [Etot] will increase Vmax.

Under physiological conditions, peptide bond formation and degradation both require enzymes, but only formation requires coupling to GTP hydrolysis. Based on this information, peptide bonds under physiological conditions are: A.both thermodynamically and kinetically stable. B.thermodynamically unstable but kinetically stable. C.thermodynamically stable but kinetically unstable D.both thermodynamically and kinetically unstable

B.thermodynamically unstable but kinetically stable. Energy input required (GTP hydrolysis) = bond thermo unstable Degration is slow (requires enzymes) = bond kinetically stable

n neurons, action potential propagation occurs along the axon. The analogous structure in skeletal muscle fibers that enables action potential propagation is the: A.actin filament. B.transverse tubule. C.motor endplate. D.myelin sheath.

B.transverse tubule. facilitate AP on individual muscle fibers

Excess fluid in the patient's lungs is most likely caused by which of the following at the pulmonary sites of gas exchange? A.Increased protein concentration in the blood flowing through pulmonary capillaries B.Decreased osmotic pressure in the interstitial fluid surrounding the pulmonary capillaries C.Increased hydrostatic pressure within pulmonary capillaries D.Decreased volume of blood flowing through the pulmonary capillaries

C. Increased hydrostatic pressure within pulmonary capillaries *Pulmonary edema * increase in hydrostatic pressure exerted on capillary walls -> High hydrostatic pressure would increase the rate of fluid leakage into the interstitial space surrounding pulmonary capillaries, causing excess fluid accumulation in the lungs.

A sodium atom in an excited state has an electron configuration of 1s2 2s2 2p6 3p1. The excited electron within the configuration was excited from the: A.2s orbital. B.2p orbital. C.3s orbital. D.3p orbital.

C.3s orbital.

Following digestion in the small intestine, certain lipids are absorbed by intestinal epithelial cells and packaged into large droplets. These lipid droplets are released from intestinal epithelial cells and transported into the lymphatic system to ultimately drain into a large vein near the heart. Which series shows the order in which these lipid droplets are transported from the intestine to the bloodstream? A.Lymph capillaries → interstitial fluid → lymph vessels → lymph duct → vein B.Interstitial fluid → lymph vessels → lymph duct → lymph capillaries → vein C.Interstitial fluid → lymph capillaries → lymph vessels → lymph duct → vein D.Lymph capillaries → interstitial fluid → lymph duct → lymph vessels → vein

C.Interstitial fluid → lymph capillaries → lymph vessels → lymph duct → vein

In individuals with glycosuria, glucose that is not reabsorbed in the proximal tubule next flows into which of the following nephron structures? A.The distal tubule B.The collecting duct C.The loop of Henle D.Bowman's capsule

C.The loop of Henle Fluid that is filtered by the kidney first enters the Bowman's capsule before passing into a long tubule, where water and solutes are selectively reabsorbed. Waste and metabolites are excreted as urine.

Difference between Chemical and Electrical Synapse

Chemical synapses use neurotransmitters to transfer information, which is a slower process. Electrical synapses transfer information from one cell to another via passive ionic current flow through gap junctions.

Found in intestinal epithelial cell wall

Cholesterol

A woman carries an X-linked recessive allele for a disorder characterized by muscle degeneration but does not express this condition. If she has multiple offspring with an unaffected man, how many of the woman's children are expected to exhibit this degenerative disorder? A.100% B.50% C.0% D.25%

D. 25% XY x XXc: XX, XcY, XY, XXc so only 25% of all offspring affected (aka only males) 25% affected, 25% carrier, 50% normal

Which organ synthesizes a compound that facilitates the mechanical digestion of lipids? A.Pancreas B.Salivary glands C.Gallbladder D.Liver

D. liver

Impaired release of which of the following neurotransmitters would directly result in the paralysis of skeletal muscles? A.Norepinephrine B.Epinephrine C.Glutamate D.Acetylcholine

D.Acetylcholine Acetylcholine (ACh), a neurotransmitter, plays an important role in the sympathetic and parasympathetic (autonomic) nervous systems. In addition, ACh is the main neurotransmitter released by neurons of the efferent somatic nervous system, the system associated with skeletal muscle function.

The (R)-enantiomer of the antiasthma drug albuterol is the active isomer. If a researcher wants to separate a racemic mixture of albuterol, which of the following methods will most likely separate the enantiomers? A.Extraction with dilute base B.Thin-layer chromatography C.Fractional distillation D.Addition of a resolving agent

D.Addition of a resolving agent

The genetic code is said to be degenerate because there are 64 different codons, but translation produces only 20 unique amino acids. The degeneracy of the genetic code is due to which mechanism? A.Exclusion of protein coding regions from mature mRNA B.Errors during tRNA charging C.Ambiguity of the tRNA for the amino acid D.Nontraditional base pairing of the anticodon with the third base of the codon

D.Nontraditional base pairing of the anticodon with the third base of the codon *This hypothesis states that the first two nucleotides on the mRNA codon require traditional (Watson-Crick) base pairing with their complementary nucleotides on the tRNA anticodon, but third nucleotide on the codon may undergo less stringent ("wobble") base pairing in a non-Watson-Crick manner. *Codon degeneracy is explained by nontraditional base pairing at the third position of the codon and anticodon.

Dehydration caused by frequent loose stools is often observed in patients with certain diseases of the gastrointestinal (GI) tract. Given this, which of the following treatments would be most effective in treating this symptom? A.Use of drugs that increase smooth muscle contractions throughout the GI tract B.Use of drugs that decrease glucose reabsorption from the small intestine C.Use of drugs that increase activity of the parasympathetic nervous system D.Use of drugs that decrease the luminal secretion of chloride ions from intestinal epithelial cells

D.Use of drugs that decrease the luminal secretion of chloride ions from intestinal epithelial cells

The compound 5,10-methylene tetrahydrofolate (5,10mTHF) is derived from folic acid (vitamin B9) and is required in the active site of the enzyme thymidylate synthase for thymine synthesis. Therefore, 5,10mTHF is most likely: A.a transcription factor. B.an inhibitor. C.an allosteric activator. D.a coenzyme.

D.a coenzyme. Vitamin is converted to coenzyme allowing enzyme to function

-DNA sequencing and Southern blotting are ____ assays are used to assess relative quantity of genes between tissue types. -Northern blotting is an _____ assay used to assess gene expression in different tissues.

DNA, RNA

Which of the following cell-cell junctions would help skin cells withstand mechanical stress by directly anchoring the intermediate filaments of adjacent cells? Desmosomes Gap junctions Tight junctions

Desmosomes -Desmosomes provide tensile strength to epithelial cell sheets by anchoring the cytoskeletons, specifically the intermediate filaments, of two cells together. -Gap junctions are cell-cell junctions that mediate communication between cells. -Tight junctions are cell-cell junctions that prevent water and solutes from diffusing between cells and across the epithelial cell layer.

Phases of the cell cycle in order

G0, G1, S, G2, M --> repeat G0: resting phase G1: pre-synthetic growth (organelle duplicates) S: DNA replication G2: Pre-mitotic growth, DNA repair M: cell division

How is GFR and Bowman's capsule related?

GFR- is the rate (amount per unit time) at which fluid is filtered out of the glomerulus and into Bowman's capsule. GFR is proportional to the hydrostatic (blood) pressure within the glomerulus. GFR decrease = afferent arterioles constrict or efferent arteriole dilate

Which is more likely to have different types of similar genes and different times? -alternate splicing, .conjugation, gene duplication, transformation.

Gene Duplication -During evolution, portions of a chromosome may be duplicated by mechanisms such as unequal crossing over.

Germ-line mutations vs Somatic mutations?

Germ-line mutations: entire organism carries genes and gives HALF to offspring Somatic mutations: part of parent is "infected" (think patch on shoulder) and passed NO part to offspring (0% chance of offspring getting if any parent has)

compact bone

Hard, dense bone tissue that is beneath the outer membrane of a bone -organized into concentric rings of bone matrix called lamellae. lamellae surrounds haversian canal (osteon), or a haversian system. Within each osteon, lacunae (spaces containing osteocytes) connect to one another via microscopic channels called canaliculi, which allow osteocyte waste exchange and nutrient delivery.

Difference between Heterochromatin and Euchromatin

Heterochromatin- highly condensed DNA tightly coiled around histone proteins. bound by an ionic interaction between the negatively charged phosphates on the DNA backbone and positively charged lysine residues in the histone. Euchromatin - less compact, histones are modified, often by acetylation of lys residues. The added acetyl group neutralizes (+) charge on the histone, reducing interactions between histones and DNA. The reduced interactions yield a more open form that is more accessible to RNAP, allowing euchromatin to be more readily transcribed.

Human cardiac muscle differs from skeletal muscle because it: A.appears striated. B.requires acetylcholine to contract. C.contains intercalated discs. D.contains cells with multiple nuclei.

Human CARDIAC muscle contains intercalated discs, straiated and has involuntary actions Skeletal: striated and voluntary actions Smooth: not started and involuntary actions

Which of the following skin functions will most likely be impaired in tissue with superficial burns? I. Keratinocyte maturation II. Immune surveillance III. Shock absorption

I and II *superficial burns damage only the epidermis -adaptive immune response emilimates foreign substances not III. hypodermic and layer under dermis composed of adipose tissue that protects internal organs by acting as shock absorber and insulator

Which step(s) of the viral life cycle would most likely occur in lytic phages? I. Injection of viral genetic material into the bacterial host II. Integration of viral DNA into the bacterial genome III. Degradation of the host genome

I and III Lytic: bacteriophage attached itself, inserts viral genome, degrades the host and then replicates to make more Lysogenic: Integration with host genome after bacteriophage had inserted viral genome in cell, cell divides and then replicates

Type 1 diabetes mellitus (T1DM) differs from T2DM in that affected patients stop producing insulin at a young age. Which of the following is most likely impaired in T1DM? I. Exocrine function of pancreatic beta cells II. Endocrine function of pancreatic beta cells III. Exocrine function of pancreatic alpha cells IV. Endocrine function of pancreatic alpha cells

II. Endocrine function of pancreatic beta cells

Secondary hyperparathyroidism may result from: I. increased intestinal calcium absorption. II. impaired renal phosphate reabsorption. III. deficient renal calcitriol synthesis.

III only

Thermregulation consist of *physiological change in skin: enhanced relaxation of arterial smooth muscle

Increasing temp: vasoconstriction, shivering, piloerection (hair) Decrease temp: vasodilation, sweating

Difference between Kinesin and Dynein?

Kinesin: Moves intracellular cargo along microtubules in anterograde axonal transport (ie, away from the nucleus and toward distal sites). Dynein: Participates in retrograde axonal transport of intracellular cargo (ie, from distal sites toward the nucleus)

CO2+H2O⇋H2CO3⇋HCO−3+H+ The patient is noted to have decreased pulmonary gas exchange. Given this, which of the following is most likely to occur in the patient's blood if this condition is left untreated?

More H2CO3 will be produced and blood pH will decrease.

As shown below, CO2 reacts with water in the blood to form H2CO3, a weak acid that can reversibly dissociate to form HCO3− and a free H+ ion. CO2+H2O⇋H2CO3⇋HCO−3+H+ The patient is noted to have decreased pulmonary gas exchange. Given this, which of the following is most likely to occur in the patient's blood if this condition is left untreated? A.More H2CO3 will be produced and blood pH will decrease. B.Less H2CO3 will be produced and blood pH will increase. C.More H+ ions will be present and blood pH will increase. D.Fewer H+ ions will be present and blood pH will decrease.

More H2CO3 will be produced and blood pH will decrease. *Pulmonary gas exchange facilitates the removal of CO2 from the blood. The amount of circulating CO2 affects blood pH by shifting equilibrium of the bicarbonate buffer system. Impaired gas exchange in the lungs will decrease blood O2 levels and increase blood CO2 levels, causing respiratory acidosis as H+ concentration increases.

Normal-phase HPLC vs Reverse-phase HPLC

Normal-phase HPLC: polar stationary phase (silica), nonpolar mobility phase of hexanes Reverse-phase HPLC: Nonpolar stationary phase (C18 hydrocarbons), Polar mobility phase (water, methanol, acetone)

PNS (peripheral nervous system) is divided into ____ and _____ which divides into _____ and _____

PNS (includes neural tissue) breakdown to: Sensory (afferent)-transmit nerve fibers to impulses to CNS & Motor (efferent)- transmit to CNS and peripheral tissues Motor further breakdown to: Somatic-voluntary impulses of skeletal muscles Autonomic- involuntary impulses of skeletal muscles

Effects of parathyroid hormone (PTH)

Parathyroid gland w/ low Ca (Hypocalcemia) -> Increase in PTH -> Increase bone osteoclast activity -> Increased [Ca]-> Ca level increase inhibits PTH hormone ---> repeat if necessary parathyroid hormone (PTH) and calcitonin are hormones that maintain calcium homeostasis by regulating calcium absorption and bone remodeling. -low blood calcium levels stimulate the parathyroid glands to secrete PTH, which then promotes several processes to elevate blood calcium levels. * PTH-induced increase in osteoclast activity.

convergent evolution

Process by which unrelated organisms independently evolve similarities when adapting to similar environments Flying Squirrel vs Flying Bat

How do retroviruses replicate?

Retroviruses are enveloped, positive-sense, single-stranded RNA viruses that convert their RNA genomes into dsDNA using the enzyme reverse transcriptase. During their lysogenic cycles, retroviruses enter the nucleus and integrate their reversed transcribed DNA with the host genome. 1. Retroviruses enter host cells through endocytosis, which allows the capsid and envelope to uncoat (disassemble). 2. Uncoating releases the viral genetic material inside the host cell. 3. RNA viruses convert their genomes (+ssRNA) into double-stranded DNA (dsDNA) using RNA-dependent DNAP before integration into the host genome can occur.

Krebs cycle irreversible steps:

The Krebs cycle is allosterically regulated at the irreversible steps catalyzed by citrate synthase, isocitrate dehydrogenase, and α-ketoglutarate dehydrogenase. *enzymes inhibited by NADH, ATP, citrate, and succinyl-CoA, and are activated by ADP and Ca2+. The Krebs cycle enzymes are not under hormonal control.

small Kd to binding tendency?

The concentration of drug that binds 50% of the receptors in the system -small Kd = low tendency to dissociate -> tight binding expected of a prosthetic group HIGH AFFINITY to bind (since only a small amount of ligand is required to achieve a high amount of binding

What is the total water loss of an eel? "...eel was transported into seawater that had been treated with the volume marker phenol red. After 20 hours, the eel's gut contained 2.3 mL of fluid but showed a phenol red concentration equivalent to 12.3 mL of ingested seawater..."

Total water loss =renal H2O loss + extrarenal water loss 10 mL = 2.3 mL + extrarenal water loss Extrarenal water loss = 10 mL − 2.3 mL = 7.7 mL -eel lost 7.7 mL H2O extrarenally.

phosphofructokinase and aldolase are examples of:

Transferase= functional group (phosphate) transferred) Lysase= bond broken + new double bond formed = lyase

parallel evolution

Two more closely related species that have made similar evolutionary adaptations after their divergence from a common ancestor

Osteocytes

a bone cell, formed when an osteoblast becomes embedded in the matrix it has secreted.

miRNA

a class of functional RNA that regulates the amount of protein produced by a eukaryotic gene Bind complementary sequences on mRNA

Hypoglycemia triggers increase in the serum level of: I. insulin II. epinephrine III. glucagon

abnormally low level of sugar in the blood II, III

Aldosterone

adrenal cortex Aldosterone is secreted by the adrenal cortex in response to elevated plasma potassium and decreased blood pressure. Aldosterone acts on the kidneys to increase Na+ reabsorption which increases H2O reabsorption and, ultimately, increasing blood volume and pressure.

If there are 15 X chromosomes in a population and 5 Y chromosome, which one by chance would be most susceptible due to chance?

allele on Y chromosome most susceptible Because alleles on the Y chromosome exist at the lowest frequencies, they are most susceptible to loss by random chance alone. THINK GENETIC DRIFT: low frequency alleles are most likely to be lost

Beta minus decay

an electron is emitted B-: 90/38 Sr + 0/1 B -> 90/39 Y *reverse for positive B

Functions of the Liver:

bile production, storage, nutrient interconversion, detoxification, phagocytosis, synthesis 1. Regulation of blood glucose 2. Storage of glycogen, minerals (iron) & vitamins 3. Synthesis of macromolecules (plasma proteins, fats, ketone bodies & cholesterol) 4. Production & secretion of bile 5. Breakdown/detoxification of numerous drugs & metabolic 6. waste products (bilirubin, ammonia)

Osteoclasts are

bone cells that resorb bone tissue

Osteoblasts

bone forming cells -promote the absorption of Ca from blood to bone tissue,

Connective tissue types

bone, cartilage, dense connective tissue, loose connective tissue, blood (Not muscle)

Emphysema/Chronic Bronchitis

breakdown of alveolar walls meaning LESS efficient gas exchange -alveoli are highly efficient at gas exchange due to their structure and extensive surface area. The destruction of alveolar walls in emphysematous lungs is expected to decrease the lungs' ability to perform respiratory gas exchange.

DNA sequencing

determine the nucleotide sequence of DNA *molecular technique used to determine the nucleotide order of DNA molecules. By analyzing the nucleotide sequences, DNA sequencing of whole genomes may be used to precisely quantify the copies of the VEGF gene present within a given tissue

freshwater fish osmoregulation

during osmoregulation, this fish takes on too much water so the kidney works to get rid of all the excess water by making diluted urine *Gain H2O, Lose Na+

-vascular endothelial growth factor (VEGF) concentrations are lowest during the post-ovulatory secretory phase (when progesterone concentration is _______ ). *VEGF concentrations within peritoneal fluid may be inversely correlated with serum levels of progesterone.

highest,

Spleen is involved in

immune function, blood storage, and the filtration and removal of senescent red blood cells from the blood. -Filters senescent (worn-out/aged) or damaged red blood cells (RBCs) from the blood. -Participates in immune function by housing macrophages that phagocytize and destroy foreign substances and by serving as a site of B cell activation -regulates blood glucose levels

Sphingolipids

long fatty acid chain polar head group backbone=amino alcohol (not glycerol) are structural lipids that help influence the fluidity and curvature of biological membranes.

How to know when genetic info close together on the chromosome?

lower probability of being separated by recombination than far apart. Fewer progeny from a cross will have recombinant genotypes than parental genotypes

Difference between Autosomal or Sex-linked genetic traits

males have only one X chromosome, sex-linked recessive traits tend to be present at greater rates in males than in females, whereas autosomal traits are present in the same proportions in both.

higher cortisol levels

means less likely to fight an incidence of disease

Compared with healthy individual's ECG, the patient's ECG shows _____ waves of AV depolarization over the same time period. *increased # of APs fired from patient's SA and AV nodal cells, lead to ___ frequent atrial and ventricular contraction *depolarization and AP generation depend on Na+, Ca+ influx into cells -- more rapid influx of (+++) ions into SA nodal cells lead to ___ APs firing from SA node and ___ frequent atrial contraction

more, more, increased, more

juxtamedullary nephrons

nephrons with well-developed loops of Henle that extend deeply into the renal medulla

DNA of telomeres can be most accurately described as:

noncoding and highly repetitive

Atoms of 18F and 19F are isotopes with what characteristics?

same chemical property (electron configuration) Different physical properties (number of neutrons)

hemoglobin curve & shifts

sigmoidal curve A left shift in the oxyhemoglobin dissociation curve signifies an increase in the affinity of hemoglobin for oxygen. This affinity is inversely related to CO2 and H+ concentrations. A left shift in the ODC therefore often indicates lower CO2 and/or acid levels in the blood.

The ATP yield of oxidative phosphorylation is directly proportional to:.

the amount of NADH and FADH2 that enters the ETC: 1.5 ATP per FADH2 and 2.5 ATP per NADH

gamma decay

the release of gamma rays from a nucleus -release of a high energy photon that occurs when the protons and neutrons in a nucleus change configuration. **It does not alter the atomic mass or atomic number of an atom.

The fluidity and rigidity of plasma membranes is partially dependent on

the structure of fatty acyl tails in the lipid bilayers. *Increasing hydrophobic interactions between fatty acyl tails leads to decreased motion and more rigidity. *The length and # of double bonds in a fatty acyl tail influence the number of hydrophobic interactions possible.

Urinary retention in patients with poorly controlled diabetes mellitus is most likely the result of nerve damage impairing smooth muscle contraction in which of the following structures? A.Bladder B.Urethral sphincters C.Kidney D.Ureter

A.Bladder Urine flows from the kidney to the bladder through the ureter. Once the bladder is full, urine exits the body via the urethra through the process of urination. Urination is controlled by the detrusor muscle (smooth muscle lining of the bladder), the internal urethral sphincter, and the external urethral sphincter.

A patient found to have an abnormally low number of helper T cells in her blood contracts a bacterial infection. During the infection, which of the following is most likely NOT affected by the patient's low count of helper T cells? A.Expression of major histocompatibility complex proteins that present bacterial antigens on the membrane of infected host cells B.Proliferation of B lymphocytes in response to the bacterial infection C.Levels of circulating antibodies against the invading bacterium D.Activation of apoptosis-inducing cytotoxic T cells

A.Expression of major histocompatibility complex proteins that present bacterial antigens on the membrane of infected host cells Helper T cells bind foreign antigens presented by other immune cells and release signaling molecules that enhance immune responses, such as cytotoxic T cell activation and antibody production by B lymphocytes.

Which statement best describes the characteristics of hormones secreted from the pituitary gland? A.Hormones secreted from the posterior pituitary are synthesized in the hypothalamus. B.Hormones secreted from the posterior pituitary act on other endocrine glands. C.Hormones secreted from the anterior pituitary only act directly on nonendocrine tissues. D.Hormones secreted from the anterior pituitary are released by depolarization of the nerve terminals.

A.Hormones secreted from the posterior pituitary are synthesized in the hypothalamus. -anterior pituitary regulates release of neurohormones into the blood from neurons located in the hypothalamus. -posterior pituitary hormones synthesized in hypothalamic neurons undergo anterograde axonal transport to the posterior pituitary. *The secretion of stored posterior pituitary hormones from the axon terminals is mediated by depolarization of the nerve terminals.

In a neuron, mitochondrial biogenesis is believed to occur primarily in the cell body, but mitochondria are often positioned at the presynaptic terminal, a distal site with high metabolic demand. Given this information, which molecular mechanism is most likely responsible for mitochondrial transport from the cell body to the presynaptic terminal? A.Kinesin motors transport mitochondria along microtubules B.Kinesin motors transport mitochondria along microfilaments C.Dynein motors transport mitochondria along microfilaments D.Dynein motors transport mitochondria along microtubules

A.Kinesin motors transport mitochondria along microtubules

Hyperventilation leads to oxygen dissociation curves similar to those seen in patients with cirrhosis when at rest. Based on this information, what physiological change in cirrhotic patients most likely decreases the level of oxygen delivery to tissues? A.Low carbonic acid and CO2 in the blood B.Increased excretion of bicarbonate by kidneys C.Higher PO2 in the lungs of cirrhotic patients D.Lower affinity of hemoglobin for oxygen in tissues

A.Low carbonic acid and CO2 in the blood

A patient is found to have reduced blood flow through pulmonary vessels and excess fluid accumulation in the abdomen and legs. Which of the following conditions would best explain this patient's symptoms? A.Reduced blood flow through the heart valve separating the right atrium and right ventricle B.Partial blockage of the heart valve separating the left ventricle and aorta C.Increased volume of blood pumped from the right ventricle D.Backflow of blood from the left ventricle into the left atrium

A.Reduced blood flow through the heart valve separating the right atrium and right ventricle

Which of the following would most likely cause an embryo to implant in a location other than the uterine lining? A.Reduced number of fallopian cilia B.Surge in luteinizing hormone prior to ovulation C.Incomplete gastrulation D.Lack of follicle rupture from the ovary

A.Reduced number of fallopian cilia * small hair-like structures within the fallopian tube called fallopian cilia help propel the fertilized oocyte toward the uterus for implantation. However, without an adequate number of cilia in the fallopian tube, improper implantation of the fertilized egg can occur outside the uterus. *Gastrulation is a post-implantation process by which a developing embryo progresses from the blastula stage to the tri-layered gastrula stage. Because this process occurs post-implantation, abnormal gastrulation would not cause implantation outside the uterus.

During asthma attack, temporary bronchoconstriction effect on blood pH, and expected homeostatic response? A.Respiratory acidosis and an increased respiratory rate B.Respiratory acidosis and a decreased respiratory rate C.Respiratory alkalosis and an increased respiratory rate D.Respiratory alkalosis and a decreased respiratory rate

A.Respiratory acidosis and an increased respiratory rate A decrease in gas exchange will cause respiratory acidosis, and the body will attempt to restore normal blood pH by increasing the respiratory rate.

If a man and a woman are having difficulty conceiving a child and decide to undergo ICSI treatment using their own gametes, which of the following represents the proper developmental pathway of the sperm cell selected to fertilize the egg during this procedure? A.Spermatogonium, spermatocyte, spermatid, spermatozoon B.Spermatogonium, spermatid, spermatozoon, spermatocyte C.Spermatocyte, spermatogonium, spermatozoon, spermatid D.Spermatocyte, spermatid, spermatozoon, spermatogonium

A.Spermatogonium, spermatocyte, spermatid, spermatozoon -Spermatogenesis is a process in which male gametes (sperm) are produced and occurs in the seminiferous tubules of the testes.--> Spermatogonia undergo meiotic division and become spermatocytes, which then become spermatids when meiosis is completed. --> Spermatids then mature into spermatozoa (mature sperm) through a series of morphological changes.

SGLT transports glucose against its concentration gradient across the luminal membrane of the proximal tubule. The energy to drive this form of glucose transport is most likely directly provided by: A.an electrochemical Na+ gradient. B.an action potential. C.ATP hydrolysis. D.simple diffusion of Na+ ions.

A.an electrochemical Na+ gradient. Primary active transport utilizes the energy from ATP hydrolysis to move a substance against its concentration gradient. Secondary active transport utilizes the energy released by the passive transport of another molecule.

Which statement most accurately describes the role of T tubules in skeletal muscle cells? A.T tubules bind acetylcholine at the neuromuscular junction to generate a depolarizing stimulus. B.Depolarizing current reaches the sarcoplasmic reticulum by traveling down T tubules. C.Muscle contraction is driven by the sliding of T tubules across one another in the sarcomere. D.T tubules sequester Ca2+ out of the cytosol to prevent prolonged muscle contraction.

B. depolarizing current reaches SR by traveling down T-tubules *For a skeletal muscle cell to contract, Ca2+ must be released into the cytosol from the sarcoplasmic reticulum (SR). Ca2+ release is induced when a depolarizing current (action potential) runs along the sarcolemma and travels down the T tubules. This current causes the nearby SR to open its Ca2+ channels, allowing Ca2+ ions to flow into the cytosol and induce the sarcomeric actin-myosin interactions required for muscle contraction.

The regulation of respiratory rate is normally most sensitive to: A.PO2 in the blood. B.PCO2 in the blood. C.PO2 in the alveoli. D.PCO2 in the alveoli.

B.PCO2 in the blood. Think: CO2 + H2O <-> H2CO3 <-> HCO3 + H chemoreceptors measure [H+] in blood and indirectly measure PCO2 in the blood

Which of the following cellular processes would most likely lead to increased genetic diversity in a population of organisms? A.DNA replication during S phase of the cell cycle B.Synapsis involving two homologous chromosomes C.Alternative splicing of gene transcripts D.Cell division via mitosis

B.Synapsis involving two homologous chromosomes *think about crossing-over

Assume a single-celled organism was discovered in water above 100°C. On closer inspection, it is determined that this organism was previously classified under the Archaea domain. Given this information, this organism most likely has: A.a peptidoglycan layer in its cell wall. B.a circular chromosome. C.telomeres. D.an endoplasmic reticulum.

B.a circular chromosome. Archaea share traits with bacteria. Like bacteria, archaea are unicellular (single-celled), have a circular chromosome, have no membrane-bound organelles or nucleus, and reproduce asexually via binary fission. (Archea just DOESNT have a peptidoglycan wall like bacteria)

Renal studies in mice have revealed that a mutation in various sodium transporters causes impaired active transport of NaCl from the filtrate within the loop of Henle to the medulla. If mice with wild-type sodium transporters were compared to mice with the mutated sodium transporters, the mutant mice would likely exhibit all of the following EXCEPT: A.decreased saltiness of the medulla. B.decreased urine output. C.decreased renal water reabsorption. D.decreased blood pressure.

B.decreased urine output. In the loop of Henle, active transport of NaCl from filtrate in the ascending limb maintains the saltiness of the renal medulla, facilitating passive water reabsorption from filtrate in the descending limb and collecting duct.

An infant who experiences seizures and has lactic acid buildup is shown to have deficient pyruvate dehydrogenase complex (PDHC) activity. Genetic analysis shows that both the maternal and paternal alleles for all PDHC subunits are normal. These results could indicate: A.overexpression of one or more PDHC subunits. B.impaired ability to synthesize lipoic acid. C.upregulated acetyl-CoA entry into the Krebs cycle. D.an unusually low rate of pyruvate fermentation.

B.impaired ability to synthesize lipoic acid. Many enzymes rely on non-amino acid components called cofactors or coenzymes to function. *The pyruvate dehydrogenase complex requires lipoic acid for activity.

VEGF signaling also leads to the dilation of existing blood vessels. One function of vasodilation is to: A.increase body temperature in cold environments. B.increase blood flow to the intestines following a meal. C.decrease blood flow to the kidneys during dehydration. D.maintain blood pressure following an episode of fluid loss.

B.increase blood flow to the intestines following a meal.

Bacteria are removed from lymph and blood in the: A.spleen and bone marrow, respectively. B.lymph nodes and spleen, respectively. C.bone marrow and lymph nodes, respectively. D.lymph vessels and thymus, respectively.

B.lymph nodes and spleen, respectively. In the lymph nodes, white blood cells remove and mount immune responses against pathogens from the lymph, whereas in the spleen, white blood cells remove pathogens and damaged or old red blood cells from the blood.

If a viral antigen were to bind to the receptors on the surface of a B lymphocyte, which of the following immune responses would NOT occur? A.Division of the B lymphocyte into cells that differentiate to secrete antibodies B.Interaction of the B lymphocyte with other immune cells that stimulate B-lymphocyte proliferation C.Secretion of toxins by the B lymphocyte that destroy nearby virus-infected cells D.Proliferation of cells that can recognize the antigen more rapidly in the event of a future infection

C.Secretion of toxins by the B lymphocyte that destroy nearby virus-infected cells *This produces many identical B lymphocytes that may differentiate into either of the following cell types: -Short-lived plasma cells secrete antibodies during the immediate immune response. -Long-lived memory cells remain in lymphoid tissues for a long time and can recognize the antigen more rapidly in the event of a future infection.

During muscle contraction, the power stroke is the pivoting motion of the myosin head that pulls the actin filament inward to shorten the sarcomere. Given this, which of the following events immediately precedes the power stroke? A.The binding of ATP to the myosin heads B.The hydrolysis of myosin-bound ATP to ADP and Pi C.The release of ADP and Pi from the myosin head D.The binding of Ca2+ to tropomyosin

C.The release of ADP and Pi from the myosin head

A pathogen identified in a patient's blood sample is found to lack a phospholipid bilayer. Therefore, any medications used to treat the disease caused by this pathogen would most likely be classified as: A.antiprotozoal drugs. B.antifungal drugs. C.antiviral drugs. D.antibacterial drugs.

C.antiviral drugs. nonenveloped (naked) viruses lack a phospholipid bilayer.

Intraperitoneal injection of insulin would cause the peptide hormone to enter the bloodstream and exert its effect on target cells by: A.acting as a second messenger. B.diffusing through the plasma membrane. C.binding an extracellular receptor. D.disassociating from a carrier protein.

C.binding an extracellular receptor.

A skin graft candidate with full-thickness burns on approximately 50% of the total BSA is at risk for all of the following EXCEPT: A.extensive fluid loss. B.bacterial infection. C.increased sensitivity to touch. D.vitamin D deficiency.

C.increased sensitivity to touch. *sensory receptors no longer work if they are burned through the epidermis and dermis

Compared to the blood flowing into the left ventricle, the blood flowing into the right ventricle: A.has a higher oxygen concentration. B.has a higher pH. C.is passing through a cardiac chamber with thinner walls. D.is passing through a cardiac chamber that contracts to produce higher pressure.

C.is passing through a cardiac chamber with thinner walls. R-ventricle has thinner walls than L-ventricle because it needs to pump blood at a lower pressure to reach only the lungs *thicker walls of L-ventricle allow it to pump blood at higher pressure to reach all other tissues in the body

Pyruvate in red blood cells can be further metabolized only by: A.phosphorylation of ADP to form ATP B.decarboxylation to form acetyl-CoA C.reduction to form lactate and NAD+ D.carboxylation to form oxaloacetate Given: red blood cells lack mitochondria, and therefore they can regenerate NAD+ only by fermentation.

C.reduction to form lactate and NAD+

Human sperm and oocytes are substantially different in all of the following aspects EXCEPT: A.cell volume. B.maturation stage at birth. C.the contribution of chromosomes to a zygote. D.the rate at which they are produced.

C.the contribution of chromosomes to a zygote. Ploidy= # of homologous chromosome sets in the nucleus of a cell. Somatic cells = 46 individual chromosomes (23 pairs). Each somatic cell has two sets/copies (2N) of each chromosome, these include 22 pairs of homologous chromosomes (autosomes) and 1 pair of sex chromosomes. mature egg and sperm are both haploid (1N) because they each contain 22 (unpaired) autosomes and 1 sex chromosome, resulting in 23 chromosomes. ** egg and sperm cell: similar in ploidy,both are haploid cells, contribute same number of chromosomes to a zygote.

One function of endothelial cells is to: A.contract to increase blood pressure. B.line the inside of the gastrointestinal tract. C.form clots at sites of vascular damage. D.line the inside of blood vessels.

D.line the inside of blood vessels. -Endothelial cells: line the interior of the CV system, includes heart, arteries, capillaries, and veins.

In humans, skeletal muscles are innervated by the somatic nervous system and function to mediate: A.blood pressure regulation. B.heart contraction. C.propulsion of food contents along the digestive tract. D.movement of the jaw during chewing.

D.movement of the jaw during chewing.

A male patient was born with an abnormal opening in the muscular wall separating the two ventricles of the heart. The opening allows blood to flow from the left to the right ventricle. If left untreated, this cardiac defect may cause any of the following in the patient EXCEPT: A.increased blood flow into the pulmonary artery. B.increased blood volume in the left atrium. C.low blood oxygen levels in systemic arteries. D.reduced oxygenation of blood flowing through the pulmonary circuit.

D.reduced oxygenation of blood flowing through the pulmonary circuit.

Cirrhosis of the liver is characterized by hepatic cell death, tissue scarring, and altered liver function. All of the following would be disrupted by cirrhosis of the liver EXCEPT: A.the production of ketone bodies. B.the metabolism of most drugs. C.the oncotic pressure within capillaries. D.the secretion of digestive proteolytic enzymes.

D.the secretion of digestive proteolytic enzymes. Ketogenesis plays important role in energy metabolism

Wedge and Dash Projection- dashes to Chair conformation

Dashes -> Down

Fate of the virus particles that fail to escape an acidified endosome

Degradation in the lysosome -lysosome serves as digestive system on the cell which would degrade various biomolecules (proteins, Carbs, nucleic acid, lipids)

In an isolated population of 10,000 rabbits, 900 are homozygous for a recessive mutant Sp1 allele. Given this, what is the percentage of rabbits in the population who carry the mutant Sp1 allele but do not express the mutant phenotype? (Note: Assume the population is in Hardy-Weinberg equilibrium.) A.9% B.21% C.42% D.70%

Hardy-Weinberg equilibrium two equations: p + q = 1: Applies to a gene with only two alleles (S and s), where p represents the frequency of one allele (S) and q represents the frequency of the other (s). p2 + 2pq + q2 = 1: Can be used to calculate frequencies of possible genotypes (SS, Ss, and ss) from the allele frequencies. Here p2 and q2 represent the frequencies of the two homozygous genotypes SS and ss, respectively. The frequency of the heterozygous genotype (Ss) is 2pq. q^2 = 900/10,000 -> q=0.3 p+q=1 -> p = 1-0.3 = 0.7 Calc Freq of alleles: 2pq = 2(0.3)(0.7) = 42%

Canagliflozin reduces blood pressure in patients with diabetes by increasing urine output and reducing total blood volume. A decrease in which of the following would also result in lowered blood pressure? I. Activation of the renin-angiotensin system II. Production of aldosterone III. Secretion of antidiuretic hormone

I, II, III

Which of the following helps maintain the resting membrane potential of a neuron? I. Passive transport II. Adenosine triphosphate III. Membrane selective permeability

I, II, III: -unequal concentration of charged ions btw the extracellular and intracellular fluid of all living cells results in an electrochemical gradient across membrane that determines the membrane potential (voltage difference). *The resting membrane potential of neurons due to high K+ and low Na+ inside the cell -protein channel presence in the cell membrane allows passive transport of certain ions down their electrochemical gradient. -Active transport pumps help maintain the concentration gradient and are critical for maintaining the resting membrane potential. -selective membrane permeability is responsible for generating the resting membrane potential in nerve and muscle cells.

The inflation of the lungs in normal inspiration involves: I. Contraction of the diaphragm II. Reduction of intrapleural pressure III. Elevation of the rib cage

I, II, and III The contraction of the diaphragm and the elevation of the rib cage decrease the pressure in the intrapleural space, causing the lungs to expand. Negative pressure breathing refers to the reduction of intrapleural pressure during inspiration.

A scientist proposed that ectopic endometrial cells contain extra copies of the VEGF gene. Given this information, which of the following techniques can be used to analyze VEGF gene count? I. DNA sequencing II. Northern blot III. Southern blot "... An enzyme-linked immunosorbent assay (ELISA) was used to characterize the concentration of VEGF protein present within these samples..."

I, III. DNA sequencing, Southern blot -Southern blot: detect a particular sequence of DNA

Compared with blood in the pulmonary veins, blood in the pulmonary arteries has higher concentrations of: I. O2 II. H+ III. CO2

II and III -oxygenated blood (high O2, low CO2, low H+) containing nutrients to all body tissues via arteries, which carry blood away from the heart. -Veins then return the deoxygenated blood (low O2, high CO2, high H+) back to the heart so that it can enter the pulmonary circuit.