Missed Question Biology - U World
D.Higher incidence of apoptosis During embryogenesis, apoptosis (programmed cell death) is crucial for normal patterning and development, **therefore, if something is abnormal, most likely is a result of apoptosis** compared to a healthy newborn, a newborn with myelomeningocele likely had a higher incidence of apoptosis induced by oxidative stress during gestation
Compared to newborns without NTDs, a newborn diagnosed with myelomeningocele would most likely have exhibited which of the following during gestation? A.Lower frequency of cell damage at critical developmental periods B.Lower cellular concentrations of free radicals C.Higher levels of antioxidant enzymes D.Higher incidence of apoptosis
D.voltage-gated ion channels clustered only at specific locations. all we are comparing is myelinated vs unmyelinated** if biologist 1 is myleinated, there will be nodes of ranvier*** which are spaces between myelin sheaths where the voltage gated ion channels will be clustered
Compared to the axons investigated by Biologist 2, the axons studied by Biologist 1 most likely had: A.faster decay of the propagating electrical signal. B.axonal membranes that were more exposed to the extracellular space. C.slower rates of action potential conduction. D.voltage-gated ion channels clustered only at specific locations.
B.insulation. hypodermis, is composed of adipose tissue that buffers rapid fluctuations in body temperature by acting as a thermal insulator. Based on the passage, the subcutaneous layer is not damaged in partial-thickness burns, so the insulation function of skin would not be affected.
Given that scar tissue forms when collagen-producing cells replace normal tissue after an injury, all of the following processes would be impaired in the area of scarred skin that forms over a partial-thickness burn EXCEPT: A.resistance to ultraviolet radiation. B.insulation. C.hair growth. D.salt excretion.
D.secrete hormones that alter blood pressure Both regions secrete hormones that regulate blood pressure and allow the body to respond to stressors.
As the two anatomical divisions of the adrenal gland, the adrenal cortex and adrenal medulla share a common feature in that both: A.synthesize steroid hormones. B.release signaling molecules into lymph vessels C.regulate the synthesis of red blood cells. D.secrete hormones that alter blood pressure
B.processing of SMN2 pre-mRNA. splicing occurs during processing NOT transcription The data presented in Figure 2 clearly show that the ASOs used in the study alleviate some of the symptoms associated with SMA. To have this effect on SMA disease pathology, ASO must alter the way the SMN2 pre-mRNA molecule is spliced. Splicing occurs during pre-mRNA processing, not during transcription.
Based on the data shown in Figure 2, which statement best explains the function of antisense oligonucleotides (ASOs) in SMA mice? ASOs affect: A.transcription of SMN2 pre-mRNA. B.processing of SMN2 pre-mRNA. C.translation of SMN2 mRNA. D.transport of SMN2 mRNA to the cytoplasm
D.I, II, and III To perform aerobic respiration more efficiently, endurance-trained type 1 fibers would likely exhibit increased mitochondrial density to improve metabolic capacity (Number I), increased capillary supply to enhance oxygen delivery to the fiber (Number II), and increased myoglobin content to ferry oxygen within the fiber more efficiently (Number III).
A scientist claims that endurance training is an exercise method that can improve physical performance by inducing changes in type 1 skeletal muscle fibers that allow the fiber to perform aerobic respiration more efficiently to generate ATP. Given this, which of the following adaptations is most likely to occur in type 1 fibers in response to endurance training? I. Mitochondrial density of the muscle fibers increases II. Capillary supply around the muscle fiber increases III. Myoglobin concentration per muscle fiber increases A.I only B.I and II only C.III only D.I, II, and III
C.80 cells 180 min - 20 minute lag phase = 160 min log (growth phase) 160 min/40 min generation time = 4 generations **multiply original number of bacterial cells by 2^n to get final population size (5 x 2^4) = 80
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
B. .25% P(child with ADPKD) = P(mother inherited A allele from her father) × P(mother passes this A allele to the child) P(child with ADPKD) = (0.5)(0.5) = 0.25, or 25%
A woman whose father is heterozygous for an ADPKD-causing mutation in PKD1 and whose mother is unaffected has a child with a man with no family history of ADPKD. What is the percent chance that their first child will have ADPKD? (Note: Assume the woman's ADPKD status is unknown.) A.0% B.25% C.50% D.100%
B.Less efficient gas exchange Emphysema is stated to cause the breakdown of alveolar walls, which would decrease total alveolar surface area. Because the alveoli are the main site of gas exchange, less efficient gas exchange is expected because less air can be in contact with respiratory tissue.
According to the passage, which of the following changes would be expected in a patient with signs of emphysema? A.Narrowing of the trachea B.Less efficient gas exchange C.Weakened diaphragm muscle D.Overstretched pharyngeal tissues
A.osmotic pressure of the tubular filtrate. (According to the passage, SGLT inhibitors can cause a decrease in blood pressure) = decrease in hydrostatic pressure in the renal artery - C is wrong)
Administration of canagliflozin most directly increases urinary output by increasing the: (According to the passage, SGLT inhibitors can cause a decrease in blood pressure) A.osmotic pressure of the tubular filtrate. B.osmotic pressure of the peritubular capillaries. C.hydrostatic pressure of the renal artery. D.hydrostatic pressure of Bowman's space
C.remove inhaled particulates. Primary ciliary dyskinesia (PCD) is stated to cause dysfunctional cilia, which would allow mucus to accumulate in the airways and result in wheezing noises. Subsequently, the ability to remove inhaled particulateswould be impaired.
Primary ciliary dyskinesia (PCD), a rare disease that impairs the normal function of cilia, is often misdiagnosed as atypical asthma because wheezing is observed in both illnesses. Unlike asthma, PCD would cause the inability to: A.balance respiratory thermoregulation. B.cough or sneeze. C.remove inhaled particulates. D.speak in lower pitches
A.Mobility and structural support Per the passage, OA is marked by erosion of articular cartilage and damage to the underlying cortical bone. However, the calcium-storing ability of bone is not impaired in OA because there is no associated loss of bone density or mass.
Osteoporosis, a disease marked by decreased bone density and mass, is similar to OA in that it is a degenerative bone disorder correlated with old age. Which two skeletal system functions would OA and osteoporosis impair, respectively? A.Mobility and structural support B.Mobility and leukocyte production C.Calcium storage and structural support D.Calcium storage and leukocyte production
B.decreased urine output. Accordingly, compared to wild-type mice, mice with mutated sodium transporters would exhibit a decrease in both medullary salt concentration (choice A) and water reabsorption (Choice C), a decrease in blood pressure (Choice D), and an increase in urine output (Choice B).
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.
D.muscle tissue. ***Types of connective tissue include bone, blood, and adipose tissue.** (Although connective tissue comes into contact with muscle tissue, muscle is not considered to be a type of connective tissue.)
Researchers analyzing gene expression in connective tissue samples are likely to obtain gene expression profiles for all of the following tissues EXCEPT: A.bone tissue. B.blood tissue. C.adipose tissue. D.muscle tissue.
B.telophase only. n mitosis, the nuclear envelope breaks down during prophase and reforms during telophase. Therefore, green fluorescence would be most intense during telophase as the nuclear envelope reforms.
Researchers are studying the last two phases of mitosis, anaphase and telophase, in actively dividing cancer cells. Different fluorescent probes are used to label various cellular components in these cells. Under the microscope, fluorescently labeled DNA appears blue, the nuclear envelope appears green, and the mitotic spindle appears red. Given this, green fluorescence would be most intense during: A.anaphase only. B.telophase only. C.both anaphase and telophase. D.neither anaphase nor telophase.
d. I, II, and III passive transport = "leak" channels ATP = sodium potassium pump
Which of the following helps maintain the resting membrane potential of a neuron? I. Passive Transport II. Adenosine triphosphate III. Membrane selective permeability a. II only b. III only c. I and III only d. I, II, and III
C.The aorta receives blood from the left ventricle. (D - wrong Deoxygenated blood from body tissues enters the right atrium via the (superior and inferior) vena cavae)))
Which of the following is generally true about the path of blood flow through the heart? A.The right ventricle contracts to propel blood to all body tissues except the lungs. B.The left ventricle pumps blood into the left atrium. C.The aorta receives blood from the left ventricle. D.The right atrium receives blood from the pulmonary veins
D.They can migrate laterally through the phospholipid-rich environment of the cell membrane A is wrong because lipid rafts are HIGH in cholesterol
Which of the following is true concerning the proteins to which AAV2 binds in Figure 1, Step 1? A.They localize primarily in low-cholesterol environments known as lipid rafts. B.They are held statically in place by cytoskeletal components. C.They are able to interact only with the phospholipids on the outer leaflet of the cell membrane. D.They can migrate laterally through the phospholipid-rich environment of the cell membrane
b. depolarizing current reaches the sarcoplasmic reticulum by traveling down T tubules
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
D. I and III only lytic life cycle: 1. attachment 2. Viral Genome entry (yes I) 3. Host genome degradation (yes III) 4. Synthesis 5. Release II is lysogenic life cycle (ntegration of viral DNA into the bacterial genome)
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 A.I only B.III only C.I and II only D.I and III only
D grafts = not good at heat loss *grafts cool down slower **in graph, if the line drops fast, this indicates poor cooling
Which table likely illustrates the change in average internal body temperature that occurred during heat tolerance testing pre-HA and post-HA in grafted and control subjects? Assume all participants had an average internal body temperature of 37°C before heat-tolerance testing began.
B.random changes in allele frequencies. genetic drift = natural variations in allele frequencies due to RANDOM genetic changes that are not related to natural selection (example: sampling error or chance event) catastrophic event that reduced population = botttleneck = reduced genetic diversity of a population Consequently, the smaller population of cheetahs has a reduced ability to buffer the negative impacts of random changes in allele frequencies (genetic drift) that may result in extinction.**** (D is wrong bc Random mating increases a population's genetic diversity) (all other options increase genetic diversity)
The cheetahs that survived the environmental catastrophe that occurred 12,000 years ago are at greater risk of extinction because of: (Namibian cheetahs experienced an environmental catastrophe that drastically reduced their population. The small number of surviving cheetahs began mating with one another, which led to severe inbreeding depression) A.naturally selected changes in allele frequencies. B.random changes in allele frequencies. C.changes in allele frequencies due to migration. D.changes in allele frequencies due to random mating
D.In a portion of the chromosome that is tightly wound around histones Because somatic cells transcribe TERT at low levels, the gene that encodes TERT is most likely found in heterochromatin within these cells. In somatic cells, the TERT gene is therefore most likely in a portion of the chromosome that is tightly wound around histones
Considering that healthy somatic cells typically transcribe the TERT gene only at low levels, where in the chromosomes of these cells is the gene most likely found? A.In a relatively open, uncoiled portion of the chromosome B.In the portion of the chromosome that binds the kinetochore C.In a portion of the chromosome that associates with ribosomes D.In a portion of the chromosome that is tightly wound around histones
B.regulation of blood glucose concentration Spleen function: -filters aged/damaged RBCs -reservoir for blood -immune response (B cell activation site, housing macrophages) pancreas is primary organ responsible for regulating blood glucose levels***
Individuals with beta-thalassemia are at risk for developing an enlarged spleen. The resulting impairment of spleen function in these individuals would NOT affect: A.immune responses against viral or bacterial infection. B.regulation of blood glucose concentration C.removal of aged red blood cells from the circulation D.storage of red blood cells
D.Leptin cannot be secreted from adipocytes In an energy-rich state (eg, after a meal), leptin is released by white adipocytes to trigger appetite suppression via the hypothalamus. An obese individual (BMI of 56 kg/m2) with a similar pathology to ob/ob mice would therefore never achieve adequate appetite suppression due to absent leptin production.
One of the study subjects with a BMI of 56 kg/m2 (Figure 2) is discovered to have a similar pathology to the ob/ob mouse. Like ob/ob mice, affected individuals exhibit normal weight at birth but become severely obese afterward and have undetectable levels of leptin in the serum. What is the best explanation for the absence of serum leptin in this condition? A.Leptin cannot bind its receptor in the hypothalamus. B.Leptin cannot bind its receptor in the thyroid gland. C.Leptin cannot be secreted from gastric cells. D.Leptin cannot be secreted from adipocytes
B.PCO2 in the blood. The regulation of respiratory rate primarily depends on the pH of the blood as measured by central and peripheral chemoreceptors. These receptors directly detect the [H+] in the blood, which is dependent on the partial pressure of CO2 in the blood through the bicarbonate buffer system.
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
A.Inhibiting and facilitating RNA polymerase binding, respectively RNA polymerases are responsible for carrying out transcription****
(TERT transcription is generally downregulated by the absence of the oncogene c-Myc and the presence of the tumor suppressor protein WT1. ) WT1 and c-Myc most likely alter TERT transcription levels by doing which of the following at the TERT gene promoter? A.Inhibiting and facilitating RNA polymerase binding, respectively B.Inhibiting and facilitating DNA polymerase binding, respectively C.Facilitating and inhibiting RNA polymerase binding, respectively D.Facilitating and inhibiting DNA polymerase binding, respectively
C.Increased environmental stress The data in the passage shows that captive male cheetahs have relatively higher susceptibility to diseases despite having increased genetic diversity. ***** cortisol = environmental stress **READ ALL PARTS OF PASSAGE/GRAPHS. (graph 1 told us that they have increased MHC diversity which would lead to increased fitness so can't be A or B)
Researchers concluded that captive cheetahs have reduced fitness because of their increased susceptibility to diseases. What can best explain the decreased fitness of captive cheetahs? A.Increased MHC diversity B.Decreased MHC diversity C.Increased environmental stress D.Decreased environmental stress
B.I and III only HBV have double-stranded genomes that are similar to the host cell's genome; as a result, this type of virus can directly utilize host enzymes. - if you knockout host machinery will be affected* won't affect HEV because +ssRNA viruses replicate their genomes in the cytoplasm of a host cell using their own viral RNA-dependent RNA polymerase. The administered compounds inhibit only the host's DNA-dependent RNA polymerase (PolII)... therefore, the HEV viral load would not decrease as a consequence of Pol II inhibition.**
Researchers perform an experiment in which they infect wild-type mice with either HBV or HEV and subsequently treat them with a drug that inhibits their cellular RNA polymerase activity. Based on the passage, administering this drug to mice infected with either HBV or HEV would result in: (HBV = double stranded genome, HEV= +ssRNA) I. Decreased viral load in HBV-infected mice II. Decreased viral load in HEV-infected mice III. Reduced number of viral fragments displayed by antigen-presenting cells in HBV-infected mice A.I and II only B.I and III only C.II and III only D.I, II, and III
C.I and II only Accordingly, this reduction in chromosome number may have occurred via: 1. end-to-end (telomere-to-telomere) fusion of two chromosomes and inactivation of one of the centromeres. This fusion would initially generate a larger chromosome with two centromeres, and inactivation of one of these centromeres would produce a single new chromosome, reducing the chromosome number in the cell by one (Number I). 2. breakage of a chromosome at the centromere and fusion of each chromosomal portion to the ends of other chromosomes. This initial breakage would result in two individual chromosomal portions. Fusion of these portions to other chromosomes would cause the original chromosome to be lost, also reducing the overall chromosome number in the cell by one (Number II). As both chromosomal events involve the transfer of intact genetic material to different chromosomes, neither would lead to a loss of coding information. In addition, because telomeres and centromeres are noncoding sequences, changes to these sequences due to chromosomal fusion or breakage would not likely affect protein-coding information.
Scientists studying evolution in yeast found that a certain species underwent a reduction in chromosome number with no loss of coding information. Given this, which of the following mechanisms best explains how this reduction in chromosome number may have occurred? I. End-to-end fusion of two chromosomes followed by inactivation of one centromere on the newly formed chromosome II. Breakage of a chromosome at the centromere and fusion of the two resulting chromosomal portions to the ends of other chromosomes III. Transfer of a DNA sequence from one chromosomal arm to a different chromosomal arm A.I only B.II only C.I and II only D.I and III only
C.gene duplication Genes with high sequence identity are evolutionarily related, having a common origin. They generally arise by gene duplication and, over time, may mutate and fulfill distinct roles within an organism. The question states that some organisms have multiple TERT genes with high sequence identity. These similar genes most likely arose by gene duplication. alternative splicing produces multiple protein products from the same gene, not multiple similar genes.**
Some eukaryotic organisms have multiple TERT genes with high sequence similarity that are expressed at different times in the organism's life cycle. These genes could have arisen by: A.alternate splicing. B.conjugation. C.gene duplication D.transformation
A.decrease the glomerular filtration rate. According to the question, stenosis is an abnormal narrowing of a blood vessel, a condition that mimics the physiological effect of vasoconstriction. As a result, 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 Higher hydrostatic (blood) pressure in the glomerulus increases GFR, and lower hydrostatic pressure decreases GFR.
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
C.I and III only cytokinesis occurs LONGITUDINALLY
T. brucei cells and higher eukaryotes are similar in that they both undergo: I. Interphase II. Prophase III. Cytokinesis A.I only B.I and II only C.I and III only D.I, II, and III
D.Anaphase II
The diagram above represents the immature gamete of a male fly that is heterozygous for Ena. If the gamete undergoes meiotic division and Ena alleles do not undergo recombination, during which phase of meiosis will the wild-type Ena alleles be pulled to opposite poles of the cell? A.Metaphase I B.Anaphase I C.Metaphase II D.Anaphase II
B.Osteocytes mesoderm = myocytes, osterocytes, erythrocytes
The germ layer that gives rise to the notochord also gives rise to which of the following cell types? ( a rodlike mesodermal structure) A.Alveolar cells B.Osteocytes C.Melanocytes D.Islet beta cells
C.The preganglionic neuron a post ganglionic neuron will always be in PNS, and cannot directly be modulated by the CNS**
The gustatory-salivary reflex can be modulated (dampened or enhanced) by input from higher centers in the central nervous system. To modulate the salivary response, descending pathways from the brain would most likely synapse onto which part of the reflex arc? A.The taste receptor B.The salivary gland C.The preganglionic neuron D.The postganglionic neuron
A.Parathyroid hormone PTH is secreted in response to low blood calcium levels and stimulates bone resorption by osteoclasts, causing an increase in blood calcium.
The information in the passage suggests that increased activity of RANK is most likely due to signaling involving which of the following hormones? A.Parathyroid hormone B.Calcitonin C.Growth hormone D.Glucagon
B. involve cells that undergo more than one round of cell division. Both spermatogenesis and oogenesis involve cells that undergo meiosis I and II. However, oogenesis in females begins in the female embryo and ends at menopause, whereas spermatogenesis in males does not begin until puberty and continues throughout a male's life.
The processes of spermatogenesis and oogenesis in humans are similar in that they both: A.begin at puberty. B.involve cells that undergo more than one round of cell division. C.result in daughter cells of unequal size compared with the parent cell. D.occur throughout the life-span of the organism
C.WT mice fed a HFD had higher insulin sensitivity than Alb Tg mice fed a HFD. However, if WT mice fed a HFD were to show significantly improved insulin sensitivity than Alb Tg mice fed a HFD, this would fail to support the hypothesis as it would mean that miR-26a overexpression in Alb Tgmice does not improve obesity-induced insulin resistance. sensitivity = opposite of resistance!!!
The researchers hypothesize that miR-26a overexpression can rescue obesity-induced insulin resistance. Which experimental result would NOT support their hypothesis? A.Alb Tg mice fed a HFD had the same levels of random and fasting insulin as WT mice fed a SHD. B.Alb Tg mice fed a HFD had the same levels of random and fasting glucose as WT mice fed a SHD. C.WT mice fed a HFD had higher insulin sensitivity than Alb Tg mice fed a HFD. D.WT mice fed a HFD had lower glucose tolerance than Alb Tg mice fed a HFD.
D.5′ - TCAAGTGATTCTCCT - 3′ since RNA polymerase reads the noncoding DNA strand to produce a complementary mRNA transcript (with uracil replacing thymine). To find coding strand: take complementary of mRNA to get anticoding and then do it again to find the original coding strand OR (Accordingly, the coding strand has the same sequence and directionality as the new synthesized mRNA transcript with one exception: The mRNA transcript has U rather than T nucleotides)
The sequence below is a portion of exon 7 of the SMN1 mRNA transcript. 5′ - UCAAGUGAUUCUCCU - 3′ Which of the following represents the corresponding DNA coding strand sequence for this particular transcript? A.5′ - AGGAGAATCACTTGA - 3′ B.5′ - TCCTCTTAGTGAACT - 3′ C.5′ - AGTTCACTAAGAGGA - 3′ D.5′ - TCAAGTGATTCTCCT - 3′
C.Reduced ventricular filling prior to contraction **manipulate the equation for VR so you get VR = ΔP/CO so increase in ΔP or decrease in CO would increase VR
The systemic blood pressure gradient ΔP is equal to the mean pressure of blood exiting the heart through arteries minus the mean pressure of blood returning to the heart through veins. The relationship of ΔP to cardiac output (CO) and vascular resistance (VR) is given by: ΔP=CO×VR Given this, which of the following physiological changes would cause increased VR within vessels of the circulatory system? (Note: Assume all other physiological factors remain constant.) A.Increased vasodilation of arteries B.Heightened activity of the SA node C.Reduced ventricular filling prior to contraction D.Decreased arterial blood pressure
B.To determine if cell specialization is influenced by communication between cells he researchers wanted to determine whether the prospective donor neural cells would continue to develop independently into nervous tissue or if they would assume a different tissue type or cell fate due to communication with surrounding cells. *** COMMUNICATION (A - wrong bc based on the description of the experiment, researchers already knew which portion of the undifferentiated gastrula would likely give rise to epidermal tissue because they were able to transplant undifferentiated prospective neural tissue onto that area)
Undifferentiated gastrula cells presumed to give rise to neural tissue were transplanted from a donor frog embryo onto an undifferentiated gastrula area of a host frog embryo. The transplantation region in the host was presumed to give rise to epidermal tissue. Both host and donor embryos were allowed to develop following the transplant, and gave rise to two normal embryos. What was the purpose of this experiment? A.To determine which cells in the gastrula ultimately give rise to epidermal tissue B.To determine if cell specialization is influenced by communication between cells C.To determine how developmental fates of cells are determined during blastula formation D.To determine whether cell differentiation could be reversed based on embryonic location
A.increasing SMN2 expression by making DNA more accessible. histone deacetylase enzymes downregulate gene expression by removing acetyl groups from histones, which reverts euchromatin back to heterochromatin, restricting transcriptional access to specific genes. Histone deacetylase inhibitors, such as valproic acid (VA), prevent removal of acetyl groups by histone deacetylases and make the genomic region containing SMN2 more accessible to RNA polymerase and transcription factors, thereby increasing SMN2 expression
Valproic acid (VA) is a histone deacetylase inhibitor that has been investigated for SMA therapy. Valproic acid most likely improves motor neuron survival by: A.increasing SMN2 expression by making DNA more accessible. B.increasing SMN2 expression by removing acetyl groups from histones. C.decreasing SMN2 expression by modifying CpG sites in DNA. D.decreasing SMN2 expression by inducing heterochromatin formation
C.Cytoplasmic reduction Fully developed sperm generally have little to nonexistent cytoplasm; therefore, reporting that the cytoplasm is reduced in sperm used for IVF would be a normal finding that is unlikely to impact fertilization rate. D - acrosomal enzymes are vital to sperm to enter oocyte A - Microtubule dysfunction would likely result in failure of the sperm cell's flagellum. Lacking a functional flagellum would impair IVF because the sperm cell still needs to be able to swim to the oocyte to fertilize it. B - If the sperm cells used in IVF had a mitochondrial deficiency, they would not have sufficient energy (ATP) to swim to the oocyte
All of the following findings in sperm would cause lower fertilization rates in IVF EXCEPT: A.Defects in microtubule structure B.Mitochondrial deficiency C.Cytoplasmic reduction D.Misfolded acrosomal enzymes
D.TfR is a monomeric protein lacking disulfide bridges Comparing the results of reducing and nonreducing SDS-PAGE, can be useful in determining whether disulfide bonds contribute to the tertiary structure of a protein.***** When SDS-PAGE is performed under reducing conditions, a reducing agent (eg, 2-mercaptoethanol) is added to disrupt disulfide bridges, allowing each subunit to separate as individual polypeptides
ApoTf and TfR were analyzed by SDS-PAGE under nonreducing and reducing conditions. Based on the gels shown, which conclusion is LEAST likely to be true? A. Gel 1 represents the nonreducing SDS-PAGE gel B.apoTf has a smaller molecular weight than TfR. C.apoTf and TfR were assigned a net negative charge. D.TfR is a monomeric protein lacking disulfide bridges
A.More H2CO3 will be produced and blood pH will decrease. decreased pulmonary gas exchange, indicating that O2 uptake into the blood and CO2 removal from the blood at the lungs is decreased. If left untreated, this condition will lead to low O2 and high CO2 levels in the patient's blood. This will shift the equilibrium of the reaction described above to the right, increasing the production of H2CO3, which in turn will dissociate, thereby increasing the presence of both HCO3− and H+ ions in the blood. Increased levels of circulating free H+ ions will lead to decreased blood pH, a phenomenon known as respiratory acidosis
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
A.0.00 the somatic L410 mutation in the mother will not be inherited by the offspring, and the probability of this woman and a genetically normal man having a child with the L410 mutation is equal to zero somatic mutations are not inherited by offspring**
Assume L410 is an acquired mutation that occurs only in hepatocytes of adults who were exposed to a certain mutagen. A woman with the L410 mutation has a child with an unaffected man. What is the probability that this child has the L410 mutation? A.0.00 B.0.25 C.0.75 D.1.00
D.bacteriophage. **thinking correctly but forgot what a bacteriophage looks like (pathogenic, circular, single-stranded RNA molecules lacking protein coats and primarily affect plants. = viroids)
Assume bacteria are infected with a vector containing HBV genetic material. This vector has been shown to introduce its genomic content into bacterial cells without fully gaining entry into the bacterial cytoplasm. Based on this information, the vector is most likely a: A.prion. B.bacterium. C.viroid. D.bacteriophage.
C.They are able to differentiate into specialized cell types of a particular tissue. Multipotent cells are able to differentiate only into the specialized cells of certain tissues and are also found in adults. (B is totipotent, A is pluripotent)
Assume that neural stem cells are considered to be multipotent. Which of the following best describes this classification of stem cells? A.They are able to differentiate into all fetal structures but not placental structures. B.They are able to differentiate into both placental and fetal structures. C.They are able to differentiate into specialized cell types of a particular tissue. D.They are able to differentiate in the zygote but not in the adult organism.
A.Reduced blood flow through the heart valve separating the right atrium and right ventricle These symptoms are best explained by reduced blood flow through the heart valve separating the right atrium and ventricle. This condition would decrease the volume of blood loaded into the right ventricle prior to contraction, reducing blood flow from the right ventricle into the pulmonary arteries. In addition, the reduced volume of blood flowing into the right ventricle and through the pulmonary circuit would cause a backup of blood in the right atrium and systemic vessels. Accordingly, blood volume and hydrostatic pressure in systemic veins would increase, causing excess fluid leakage from systemic vessels into the surrounding interstitial fluid and subsequent fluid accumulation (edema) around tissues.
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
C.I and III only DNA sequencing/Southern blot can tell us relative gene count/concentration of DNA Northern Blot= RNA northern blots assess gene EXPRESSION within a tissue
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 A.I only B.II only C.I and III only D.II and III only
D.Species D species D diverged first and is least similar to the common ancestor because it accumulated more mutations over time species that diverged more recently from a common ancestor have accumulated fewer mutations across a shorter time and are more genetically similar to one another and their common ancestor. In contrast, species that diverged less recently (eg, a long time ago) from a common ancestor have accumulated more mutations across a longer period and are less genetically similar to one another and their common ancestor.
A scientist sequences the genomes of several species and analyzes their evolutionary relationships to a single common ancestor. The percentage of similarity between the genome of each species to the genome of this answer is calculated and shown in the table: Which species diverged from the common ancestor first? a. Species A b. Species B c.Species C d.Species D
B.1,350 mRNA nucleotides must be translated to form a fully functional 50-kDa LPL protein. If 225 residue monomers (homodimer) x 2 = 450 -450 reside x 3 nucleotides/residue = 1,350 nucleotides -450 residue dimer x 110 dA/aa = 45000 ~ 45 kD
A scientist studying the sequence of the homodimer of LPL would most likely expect that: A.675 mRNA nucleotides must be translated to form a fully functional 50-kDa LPL protein. B.1,350 mRNA nucleotides must be translated to form a fully functional 50-kDa LPL protein. C.675 mRNA nucleotides must be translated to form a fully functional 25-kDa LPL protein. D.1,350 mRNA nucleotides must be translated to form a fully functional 25-kDa LPL protein
D.Anaphase I chromosomal nondisjunction occurs when homologous chromosomes (in meiosis I) or sister chromatids (in meiosis II) fail to separate to opposite poles of the cell during anaphase, leading to extra chromosomes in some daughter cells and missing chromosomes in others.
A single diploid cell containing 46 chromosomes underwent meiosis and produced four daughter cells, two with 22 chromosomes and two with 24 chromosomes. An error in which of the following stages of meiosis would most likely explain this result? A.Metaphase II B.Prophase II C.Telophase I D.Anaphase I
C.mimics the activity of sympathetic neurons The passage states that norepinephrine and epinephrine release is stimulated by ACh-mediated signaling in the sympathetic component of the autonomic nervous system Accordingly, for a drug to trigger an increased secretion of norepinephrine and epinephrine by the adrenal medulla, the drug must generate effects that mimic the activity of the sympathetic nervous system.
Administration of a drug causes increased secretion of norepinephrine and epinephrine by the adrenal medulla. This most probably occurs because the drug: A.increases secretion of ACTH. B.inhibits production of TH and AADC. C.mimics the activity of sympathetic neurons D.activates enzymes that mediate the breakdown of tyrosine derivatives
B.trypsinogen. trypsinogen is in the small intestine!! The pancreas generally secretes proteolytic enzymes (eg, trypsinogen, chymotrypsinogen) into the pancreatic duct, which empties into the duodenum to aid digestion of chyme in the lumen. However, in RYGB patients, the duodenum is located in the biliopancreatic limb. Accordingly, pancreatic trypsinogen is released from the pancreas and secreted into the duodenum within the biliopancreatic limb, not the alimentary limb.
All of the following are secreted by cells in the alimentary limb of RYGB patients EXCEPT: A.pepsinogen. B.trypsinogen. C.gastrin. D.mucus.
C.8 hours To complete one cycle, a cell starting in any phase must pass through all other phases and return to the phase in which it began. ** therefore would be 8 hours
Based on Figure 2, in the absence of VX-680, how long does it take T. brucei cells released from S phase at 0 hours to complete one full cell cycle? A.4 hours B.6 hours C.8 hours D.10 hours
C.miR-19 without 19 you get higher apoptosis so must be working in cancer normally to supress apoptosis
Based on Figure 2, which family from the miR-17~92 gene cluster is expected to contribute the most to cancer progression? A.miR-17 B.miR-18 C.miR-19 D.miR-92
B.GTP binding to the G-protein alpha subunit GTP binding to alpha subunit = ACTIVATES second messenger cascade) (Calcium binds to PKC not PLC - C) (PLC is activated by the GTP-bound alpha subunit of the G-protein, not ATP - D)
Based on the passage and the experimental results shown in Figure 1, which event is an outcome of treating hCaSR cells with AMG 416? (hCaSR activation ultimately inhibits PTH release by inducing a second messenger cascade in which intracellular calcium levels rise due to the hydrolysis of the membrane phospholipid phosphatidylinositol bisphosphate (PIP2) into inositol trisphosphate (IP3) and diacylglycerol (DAG) by the membrane-bound enzyme phospholipase C (PLC).) (AMG 416=hCaSR agonist) A.PTH binding to the G-protein alpha subunit B.GTP binding to the G-protein alpha subunit C.Calcium binding to phospholipase C D.ATP binding to phospholipase C
C.Interstitial fluid → lymph capillaries → lymph vessels → lymph duct → vein Fluid is collected by lymph capillaries, flows into larger lymph vessels, and is transported into lymph ducts that drain into veins near the heart.
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
A.inhibiting proteins that mediate glycogen synthesis.
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.
c. Secretion of toxins of the b lymphocyte that destroy nearby virus-infected cells Natural killer and cytotoxic T cells, not B lymphocytes, respond to antigens by releasing toxins that induce apoptosis (cell death) in nearby infected cells. On binding antigens presented by B lymphocytes, helper T cells release cytokines (signaling molecules) that stimulate B-lymphocyte proliferation (Choice B) Short-lived plasma cells secrete antibodies during the immediate immune response (Choice A). 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 (Choice D).
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 of 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.leukocyte production. Kidneys play a role in regulating the homeostasis: -blood pressure - waste removal -osmolarity -blood pH -erythrocyte production therefore leukocyte production would not be affected - Production of leukocytes (white blood cells) occurs in the bone marrow, not the kidneys.
In advanced ADPKD, all of the following components of physiological homeostasis would be disrupted EXCEPT: A.blood nitrogen levels. B.blood pH. C.leukocyte production. D.erythropoietin production
A.An allele on the Y chromosome Because alleles on the Y chromosome exist at the lowest frequencies, they are most susceptible to loss by random chance alone****
In the combined population of 15 X chromosomes and 5 Y chromosomes, which of the following alleles, if any, would be most susceptible to loss due to random chance alone? A.An allele on the Y chromosome B.An allele on the X chromosome C.An allele on either the X or Y chromosome D.Allele loss due to random chance alone would only occur in nonsex chromosomes
B.Deposition of excess bone on the epiphyses of affected long bones SAYS ITS ADDING TO THE OUTSIDE* therefore is not gonna affect marrow and will be adding
OA commonly affects large, weight-bearing joints of the lower extremities such as the knee and hip. Based on the passage, which of the following would occur in a patient with OA involving the knees? A.Deterioration of the yellow bone marrow in affected bones B.Deposition of excess bone on the epiphyses of affected long bones C.Reduction of hematopoiesis in the red marrow of affected bones D.Degeneration of compact bone at the diaphysis of affected long bones
D.line the inside of blood vessels. endothelial cells = single-cell layer that makes up the innermost surface of the cardiovascular system (heart and blood vessels).**
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.
B.high numbers of macrophages near the cut. Macrophages, phagocytic immune cells, engulf and destroy foreign pathogens and damaged cells. Although these cells may destroy pathogens entering the body through the cut, they would not inhibit clot formation and cause the excessive bleeding observed in the patient. (liver = Clotting factors (mainly synthesized in the liver) are specialized proteins that become activated in response to platelet aggregation and signaling factors outside the vessel.)
A physician finds that a patient experiences excessive bleeding after sustaining a cut on the arm. The excessive bleeding is LEAST likely to be caused by: A.reduced liver function. B.high numbers of macrophages near the cut. C.reduced proliferation of platelets. D.high levels of serum antibodies against clotting factors
D.Active transport H+ is going against its concentration gradient***
As it matures, the endosomal lumen becomes acidified relative to the cytosol. Protons from the cytosol most likely enter the endosomal lumen by which of the following processes? A.Simple diffusion B.Facilitated diffusion C.Passive transport D.Active transport
C.A template sequence containing deoxyribonucleotides
Based on the passage, which of the following reagents was most likely used during PCR? A.Free ribonucleoside triphosphates B.RNA polymerase C.A template sequence containing deoxyribonucleotides D.Primer pairs with minimal GC content
B.It has reverse transcriptase function. discovered a new strain of hepatitis (HXV) by ****analyzing chromosomal DNA of patient's liver cells**** = virus is a retrovirus because it integrated with the host genome (DNA)!!!!
Physicians researching a global hepatitis outbreak discover a new strain of hepatitis (HXV) by analyzing chromosomal DNA of patient's liver cells. They found that HXV has a +ssRNA genome and replicates through DNA intermediates. What characteristic best describes the new hepatitis virus? A.It integrates its retroviral +ssRNA into the host genome. B.It has reverse transcriptase function. C.It synthesizes a complementary RNA strand. D.It translates its own proteins
D SnRNAs are involved in splicing** therefore the product will be smaller than the unprocessed piece
Researchers have discovered that SMN plays a role in its own mRNA processing, and that FL-SMN enhances the expression of small nuclear RNAs (snRNA) required to produce mature FL-SMN mRNA. In motor neurons of SMA patients, the feedback mechanism between SMN protein and SMN mature mRNA is shown in which northern blot sample?
D.Thyroid Calcitonin = a hormone synthesized by the thyroid gland**
Researchers treated 5/6 Nx mice with regular intraperitoneal infusions of CaCl2 to cause a sustained increase in serum calcium levels. The hormone that was released as a result of this condition was monitored using a hormone-specific radiolabeled antibody. In the tested animals, what organ would most likely show increased binding of radiolabeled antibody? A.Thymus B.Pancreas C.Bone marrow D.Thyroid
B.Plasma membrane IN BACTERIA!!!!!!!!! only answer choice in bacteria out of all of these choices is PLASMA MEMBRANE
SOD mRNA in P. leiognathi encodes a signal sequence that directs the transport of the SOD protein for secretion. This signal sequence will direct SOD proteins to which structure in P. leiognathi? A.Smooth endoplasmic reticulum B.Plasma membrane C.Mitochondrial outer membrane D.Golgi body
B.the liquid portion of blood. Plasma is the liquid portion of blood and is ~90% water, with the remaining 10% composed of other substances (eg, proteins, respiratory gases). Once secreted from liver cells, the shortened transferrin enters circulation and is incorporated into the plasma.
Transferrin circulating in the blood consists of 679 amino acids, but it is composed of 698 amino acids when it is post-translationally extracted from liver cells, the primary site of transferrin synthesis. Given this information, researchers would most likely be able to extract and isolate the shorter transferrin peptide from: A.lymph. B.the liquid portion of blood. C.all cellular elements of blood. D.the nucleus of a liver cell.
A.Increased blood volume and increased serum sodium content Aldosterone acts on the kidneys to increase the reabsorption of sodium, which in turn leads to increased reabsorption of water and, ultimately, increased blood volume and pressure.***
What changes in blood volume and serum sodium content would be expected as a result of using synthetic hormones to replenish aldosterone in CAH patients? A.Increased blood volume and increased serum sodium content B.Increased blood volume and decreased serum sodium content C.Decreased blood volume and increased serum sodium content D.Decreased blood volume and decreased serum sodium content
C.It serves as an attachment that holds bones to muscle. Ligaments and tendons are important connective tissue structures at joints. Tendons (not hyaline cartilage) tautly anchor muscle to bone.**** - a and d true: because cartilage lacks nerves (ie, is not innervated) and is avascular (ie, lacks its own blood supply), it must receive nutrients and oxygen via diffusion from surrounding fluids or vascularized areas -b true: The process of endochondral ossification utilizes hyaline cartilage as a template for bone deposition
Which of the following statements is NOT true about hyaline cartilage? A.It lacks innervation. B.It gives rise to bone through endochondral ossification. C.It serves as an attachment that holds bones to muscle. D.It is avascular and receives nutrients from surrounding fluids
C.increased sensitivity to touch. THEY LOST THOSE RECEPTORS according to the passage, the damage associated with a full-thickness burn extends through the epidermis and dermis and into the subcutaneous layer (hypodermis). Therefore, this type of burn involves injury to the epidermal and dermal sensory receptors, resulting in impaired touch sensation. a - An individual with full-thickness burns would be less able to retain fluids and electrolytes because the physical barrier that normally seals water inside the body (the skin's outer layer) has been damaged or lost. d - skin is one way we get vitamin D: If individual has full thickness burns, the skin is no longer able to contribute as effectively to the overall level of vitamin D in the body.
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
D.One-quarter For the cross between a female carrier of an X-linked recessive trait and an unaffected man, only male children will express the trait. The probability of a child having the trait is given by P(child inherits affected X-chromosome from mother) × P(child is male) = 0.5 × 0.5 = 0.25. Therefore, 25% of all offspring will express the trait.
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.All B.Half C.None D.One-quarter
B.decrease only ***read graph in detail*** was told high levels or cortisol added which has negative feedback on CRH so In addition to mediating the stress response, cortisol also inhibits CRH release from the hypothalamus and ACTH release from the pituitary gland. By inhibiting the secretion of CRH and ACTH, secreted cortisol increases negative feedback such that the adrenal cortex receives less stimulatory input and the synthesis and secretion of additional cortisol decrease.
A woman with low serum cortisol due to partial adrenal dysfunction is treated with high doses of a synthetic cortisol analogue. According to Figure 2, treatment with a cortisol analogue will most likely cause this patient's serum level of endogenous cortisol to: A.increase only. B.decrease only C.remain the same. D.increase at first, but then decrease over time.
B.calcium transfer from the bloodstream into bone tissue. osteoblasts, promote the absorption of calcium from blood to bone tissue, are most important in promoting the activation and differentiation of OPCs.*****
Based on the passage, the cells that are most important for the differentiation of OPCs are cells that promote: (he passage states that RANKL is a ligand expressed by osteoblasts that binds RANK, a transmembrane receptor expressed by OPCs. The binding of RANKL on osteoblasts to RANK on OPCs induces downstream signaling pathways that lead to the differentiation of OPCs into mature osteoclasts) A.calcium transfer from bone tissue into the bloodstream. B.calcium transfer from the bloodstream into bone tissue. C.acid production in bone tissue. D.proteolytic enzyme production in bone tissue.
B.a higher number of juxtamedullary nephrons and a lower number of cortical nephrons compared to their ancestors.
Camels inhabit water-deficient environments and exhibit an evolutionary adaptation that allows them to absorb more water than their ancestors that dwelled in water-rich environments. The diagram below shows the structure of two nephron types present in the kidneys of camels and other mammals. How would the number of cortical nephrons differ from the number of juxtamedullary nephrons in camels and their ancestors? Camels would be expected to have: A.a lower number of juxtamedullary nephrons and a higher number of cortical nephrons compared to their ancestors. B.a higher number of juxtamedullary nephrons and a lower number of cortical nephrons compared to their ancestors. C.a similar number of juxtamedullary nephrons and a lower number of cortical nephrons compared to their ancestors. D.a similar number of juxtamedullary nephrons and a higher number of cortical nephrons compared to their ancestors.
C.contained fewer oxygen-storage proteins than muscle fibers in cross section 2. Darkly stained fibers in cross section 2 indicate high enzyme activity and the presence of many mitochondria, making them mostly oxidative. In contrast, minimally stained fibers in cross section 1 indicate low enzymatic activity (ie, fewer mitochondria), signifying that these fibers are primarily nonoxidative.
Civen these results, muscle fibers in cross section 1 most likely: A.utilized more oxygen than muscle fibers in cross section 2. B.relied on anaerobic respiration less than muscle fibers in cross section 2. C.contained fewer oxygen-storage proteins than muscle fibers in cross section 2. D.had a more extensive network of surrounding blood vessels than muscle fibers in cross section 2
C.II and III only Within the pulmonary circuit, the pulmonary arteries carry CO2-rich, O2-poor blood from the heart to the lungs, where CO2 is exchanged for O2. The pulmonary veins then carry CO2-poor, O2-rich blood from the lungs to the heart, which then pumps the oxygenated blood to all body tissues.
Compared with blood in the pulmonary veins, blood in the pulmonary arteries has higher concentrations of: I. O2 II. H+ III. CO2 A.I and II only B.I and III only C.II and III only D.I, II, and III
D.Use of drugs that decrease the luminal secretion of chloride ions from intestinal epithelial cells In this scenario, dehydration is caused by frequent loose stools in affected individuals. Loose (watery) stools may be due to decreased water absorption or increased water secretion in the intestinal tract. Chloride (Cl−) secretion from intestinal epithelial cells would increase the osmotic pressure of intestinal contents, drawing more water into the intestine and increasing the water content of stool. Therefore, drugs inhibiting luminal secretion of Cl− would likely decrease water secretion into the intestine and make the stools less watery.
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
A.Respiratory acidosis and an increased respiratory rate According to the passage, the constriction of the airways in asthma restricts inhalation, and therefore a decreased volume of fresh air will be available for gas exchange in the lungs. Due to less efficient gas exchange, less CO2 is removed from the blood and blood CO2will build up. An increase in blood CO2 shifts the equilibrium to the right, increasing [H+] (pH decreases). The decrease in blood pH due to decreased gas exchange is known as respiratory acidosis. In response to the change in blood pH, the respiratory center of the nervous system will attempt to restore the balance of CO2 and H+ in the blood by changing the rate of respiration. An increased respiratory rate(hyperventilation) will increase the amount of CO2 removed from the blood, shifting the equilibrium of the bicarbonate buffer system to the left, decreasing [H+] and increasing the blood pH back to normal.
During an asthma attack, temporary bronchoconstriction would have what effect on blood pH, and what would be the 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
C.The release of ADP and Pi from the myosin head
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. exhibit impaired cholesterol synthesis in the smooth endoplasmic reticulum of adrenocortical cells. patients with adrenal insufficiency caused by defective SER proteins would not respond to ACTH administration as a treatment ACTH cannot increase cortisol production de to impaired cholesterol synthesis.
For individuals who exhibit insufficient hormone production by the adrenal cortex, ACTH is sometimes administered as a treatment option. Clinicians have reported that most patients fail to respond to this treatment with ACTH. The most likely reason for this outcome is that nonresponsive patients: A.release insufficient amounts of ACTH from the pituitary gland. B.continuously overexpress the genes for DBH and PNMT. C.exhibit impaired cholesterol synthesis in the smooth endoplasmic reticulum of adrenocortical cells. D.express an overactive ACTH receptor on cells responsive to cortisol
C.Increased hydrostatic pressure within pulmonary capillaries
Given the information in the passage, the 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
B.receptors for glucocorticoid hormones are expressed in diverse tissue types. in glucocorticoid deficiency, an insufficient amount of glucocorticoid hormones in the blood leads to diminished binding of these hormones to their receptors. This condition would compromise the normal function of the various cells that express glucocorticoid receptors.
Glucocorticoid deficiency is known to impair healing of superficial wounds, memory formation, and other physiologic phenomena. This deficiency most likely leads to these wide-ranging effects because: A.glucose is the primary energy source in many of the body's tissues. B.receptors for glucocorticoid hormones are expressed in diverse tissue types. C.glucocorticoids modulate thyroid hormone release by the thyroid gland. D.hyperplasia of adrenal tissue in CAH causes damage to several nearby organs
D.No; neural crest cells continue to act normally as temporary migratory cells that give rise to other cell types Because the neural crest cells derive from the residual portions of the neural folds that do not contribute to neural tube formation, they are likely not involved in myelomeningocele pathology and continue to act normally as temporary migratory cells that give rise to a diverse lineage of cells. (B os wrong bc Neural crest cells are not associated with myelomeningocele pathology (neural tube closure) as they do not contribute to the formation of the brain or spinal cord (ie, CNS).)
Neural crest cells migrate away from the neural tube to give rise to most of the peripheral nervous system. Given this information, would neural crest cells be involved in the pathology of myelomeningocele? A.Yes; neural crest cells secrete signals that directly inhibit neural tube closure. B.Yes; neural crest cells fail to differentiate into the posterior spinal cord. C.No; neural crest cells continue to differentiate into glial cells of the brain. D.No; neural crest cells continue to act normally as temporary migratory cells that give rise to other cell types
C.Yes, because RYGB increases the pH of gastric juice less stomach = less acidic so increase pH and increase ionization
Nonsteroidal anti-inflammatory drugs (NSAIDs) are weakly acidic compounds that normally pass through the acidic environment of the stomach in a nonionized form until they reach the small intestine, where they become ionized in the less acidic lumen. Ionized NSAIDs, shown below, are more soluble and therefore dissolve faster. Would NSAID solubility in the gastric pouch of postoperative RYGB patients be higher than normal? A.No, because RYGB decreases the pH of gastric juice B.No, because RYGB increases the pH of gastric juice C.Yes, because RYGB increases the pH of gastric juice D.Yes, because RYGB decreases the pH of gastric juice
D.mICSI is a more successful technique than IVF and ICSI in the BCB− group POINTING TO JUST BLASTOCYSTS stage -Oocytes (not blastocysts) were supplemented with mitochondria prior to ICSI, not IVF. The passage makes no mention of mitochondrial incorporation in combination with IVF treatment. - b wrong - c wrong The passage provides no information on the fate of blastocysts that continue development.
What conclusions can be made about the production of blastocysts by the fertilization methods shown in Table 1? A.ICSI is a less accurate fertilization method than IVF. B.ICSI allows mitochondria to be more readily incorporated into the blastocysts than IVF. C.Blastocysts generated by IVF are more likely to become inviable. D.mICSI is a more successful technique than IVF and ICSI in the BCB− group
A. Degradation in the lysosome Step 6 cannot enter the Golgi or other secretory pathway organelles to undergo exocytosis (Choice B). The only other available fate is the lysosome, where AAV2 particles will be degraded.
What is the fate of the virus particles that fail to escape the acidified endosome in Figure 1, Step 6? (The passage states that AAV2 inhibits retrograde trafficking of the endosomal pathway***) A.Degradation in the lysosome B.Repackaging in the Golgi followed by exocytosis C.Reprocessing in the endoplasmic reticulum D.Destruction by a proteasome
B.Enhanced relaxation of arteriole smooth muscle When body temperature is above normal (as would occur during HA exercise), the following processes cool the body (ie, decrease body temperature): Vasodilation (widening) of skin arterioles increases blood flow to skin capillaries and maximizes heat loss through the skin.. Vasodilation occurs when the smooth muscle surrounding the blood vessels relaxes
What physiological change occurs in the skin of control subjects during HA exercise? A.Enhanced contraction of arteriole smooth muscle B.Enhanced relaxation of arteriole smooth muscle C.Enhanced contraction of arrector pili muscles due to parasympathetic activation D.Enhanced contraction of arrector pili muscles due to sympathetic activation
A.I and II only 1. 5' G-C cap is a 5' to 5' linkage prevents degradation by 5' to 3' endonucleases and also signals to ribosome that the 5' end is intact 2. Poly AAA tail, 3' end repetitive sequence of A's that is added. Also protects the end and signals lack of damage to the ribosome 3. Splicing introns are removed and exons are spliced to each other. Alternative splicing is a way to use the same gene to make multiple variations of a given protein
What steps are required to produce a mature FL-SMN transcript? I. Excision of noncoding sequences between the 3′ and 5′ untranslated regions in pre-mRNA II. Addition of multiple adenine nucleotides to the 3′ end of SMN1 pre-mRNA III. Removal of the 7-methylguanosine cap from mature mRNA IV. DNA polymerase binding to the SMN1 gene A.I and II only B.III and IV only C.I, II, and IV only D.I, II, III, and IV
B.Only a small percentage of the progeny are recombinant. Given this small percentage of recombinant flies, it is likely that the PTP and Abl genes are close together on the chromosome. two genes are located close together on a chromosome, they are relatively unlikely to be separated by a recombination event. This is because there is less distance between the two genes in which a recombination can occur. Therefore, substantially fewer progeny will have recombinant combinations than parental combinations.
Which evidence in Table 1 suggests that PTP and Abl are located close together on the chromosome? A.The two recombinant genotypes occur with similar frequency. B.Only a small percentage of the progeny are recombinant. C.Recombination did not occur in male gametes. D.The F1 generation has a high recombination frequency
D.Erythrocytes Erythrocytes contain no mitochondria as they expel their organelles during the maturation process in the bone marrow. As a result, mitochondrial mutations do not affect erythrocytes. (A - Hepatocytes are specialized cells in the liver that contain mitochondria and generate energy for the synthesis of proteins, carbohydrates, and lipids as well as the detoxification of metabolites and drugs)
Which of the following cell types would be LEAST sensitive to mitochondrial dysfunction due to mtDNA mutation? A.Hepatocytes B.Neurons C.Myocytes D.Erythrocytes
B.Synapsis involving two homologous chromosomes synapsis = the joining of homologous chromosomes into tetrads occurs during prophase I of meiosis and is required for crossing over to occur. **allows for crossing over (alternative splicing can increase protein diversity, but not genetic makeup)
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
A.Hormones secreted from the posterior pituitary are synthesized in the hypothalamus. posterior pituitary hormones are synthesized in hypothalamic neurons and undergo anterograde axonal transport to the posterior pituitary. **
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
