B/B
what would increase ETC activity more: NADH or FADH2?
NADH because it pumps more protons into the inter membrane space so we can make more ATP
What is considered upstream and downstream on DNA?
NO 0 ON DNA upstream to the right (positive numbers) downstream to the left (negative numbers) this is similar to HNMR -- upfield/shielding is to the right and downfield/deshielding is to the left
do prokaryotes use cilia?
NO ONLY EUKARYOTES prokaryotes have filament (flagella) to move fimbriae/pili surrounded the bacteria which extend out to connect with other bacteria
Can a bacteria or virus cause an automize disease?
NOOO autoimmune disorders by definition are caused by immune reactions to antigens produced by the body itself, not by antigens from other organisms
if I am using DNA to run my gel electrophoresis then what kind of gel am I most likely running? when do we use reducing agents and denaturing agents?
Native page denaturing is usually just for proteins to turn them into their primary structure and reducing agents (reducing conditions) are used only for PROTEINS to break up the disulfide bonds
nucleotide vs nucleoside
Nucleotide= phospate sugar nitrogen base nuceoside= sugar and nitrogen base
what happens with the glucose metabolic pathways when starving?
gluconeogensis is upregulated so that pyruvate (+other precursors) can be used to make glucose glycolysis is downregulated
glutamine vs glutamate vs guanine
glutamine (Q) -CH2-CH2-CONH2 glutamate (E) -CH2-CH2-COOH guanine = nitrogenous base
what are the AAs that cause issues for alpha-helices?
glycine- increased flexibility proline- causes kinks for the rest of the AAs: hydrophobic AA found on inside and hydrophilic found on outside
what kind of linkages does glycogen synthase make? branching enzyme?
glycogen synthase: alpha 1,4 glycogen branching enzyme: alpha 1,6
The cell type in the male reproductive system that is most analogous to the female ovum is the: a. spermatogonium b. primary spermatocyte c. spermatid d. spermatozoon
The mature ovum is the female gamete that has completed meiosis and contains the haploid number of maternally derived chromosomes. This makes it most analogous to spermatozoa, the mature male gametes that contain the haploid number of paternally derived chromosomes. Thus, D is the best answer.
Fever in septic shock leads to which of the following compensation mechanisms? A. dilation of capillary beds in the skin B. increased skeletal muscle activity C. decreased respiration rate D. decreased fluid loss
To compensate for the increased body temperature in a fever, skin capillaries dilate to dissipate heat through the skin. Skeletal muscle activity in the form of shivering may occur, but this generates heat, rather than dissipating it. Decreased respiration rate and decreased fluid loss also limit, rather than increase, dissipation of body heat. Thus, answer choice A is the best answer.
what does it mean there is increased hemoglobin in plasma?
Under normal conditions hemoglobin is carried in red blood cells and is not found in the plasma. If there is a bunch of hemoglobin in the plasma, then that is most likely because the red blood cells ruptured and hemoglobin was released into the plasma -- aka hemolysis (rupture of RBC) is taking place
What is catabolism in the body-- what does it make?
break down molecules Energy containing nutrients: carbs, fats, proteins Form: NADH, NADPH, FADH2, ATP and make energy depleted products: H2O, CO2, NH3 this is because our macromolecules are what make energy in the body ex. one Q asked what catabolism requires and the answer was: it requires NAD+ as an oxidizing agent to produce NADH
what affect does albumin have in blood stream?
controlling osmotic pressure, it draws salts in so water follows if it draws salts in, then it can make the concentration of salt inside higher than outside so album makes the blood vessels hypertonic (more concentrated) in relation to the tissue.... fluid would go from the tissue to the blood vessels
What enzyme activates trypsinogen into trypsin?
enterokinase (aka enteropeptidase)- enzyme produced by cells of the duodenum and is involved in digestion in humans and other animals Trypsin- enzyme in the small intestine that breaks down proteins, continuing the process of digestion that began in the stomach. It may also be referred to as a proteolytic enzyme
what do you infer is the baseline if the y-axis is a percentage?
the baseline is probably at 100% and the things above the baseline means increase and things below the baseline mean decrease
Which of the following processes is LEAST directly influenced by adrenergic drugs? A. perastalsis B. secretion of digestive enzymes C. enzymatic breakdown of food molecules D. nutrient delivery to muscles and organs
the correct answer is C. The question asks the examinee to identify the bodily process among the options listed that is LEAST directly influenced by adrenergic drugs. According to the passage, adrenergic drugs mimic activation of the sympathetic nervous system; therefore, the best answer will be the process that is LEAST directly controlled by the sympathetic nervous system. The sympathetic nervous system directly inhibits peristalsis (A) and secretion of digestive enzymes (B). It also increases the blood glucose concentration and causes dilation of the blood vessels that supply the deep muscles and internal organs, which aids nutrient delivery (D) to these tissues. The sympathetic nervous system does not directly affect the activity of digestive enzymes (C) after they have been secreted. Thus, C is the best answer.
when the native (nature) state of proteins are lost, what happens?
the hydrophobic AAs become exposed to the aqueous environment which is unfavorable and increases instability so to help minimize this, proteins begin to aggregate to avoid unfavorable interactions (due to hydrophobic effect) decrease SA cause precipitate to form
what is the main driving force of tertiary protein structures?
the hydrophobic effect... it causes the protein to spontaneously arrange in a manner where hydrophobic is on the inside and hydrophilic is on the outside **allows the protein to fold protein folding is stabilized by van der waal forces, H-bonds, disulfide bonds, salt bridges aka ionic bonding aka electrostatic interactions aka between acidic and basic side chains like negative and positive charges, hydrophobic interactions
How does length, pH, and salinity affect DNA?
the longer the DNA, the harder it is to denature and reanneal DNA because you're working with more nucelotides/base pairs pH- when optimal pH is altered the DNA becomes denatured and the H bonding is messed up salinity- salts like Na+ (NaCl) and Mg2+ (MgCl2) dissociate into cations which can go and bind to the negative charges on DNA which cause so much repulsion -- so by increasing salinity you are able to stabilize the DNA structure DNA's repulsion is usually overcome by H-bonding between bases and phosphodiester bonds
What is the F1 generation?
the offspring of the P generation the first filial generation So if parents are RR and rr then F1 is Rr to find F2 you would just do Rr x Rr so F2 would be RR, Rr, Rr, rr --> 50% resembles F1 and 50% resembles the P generation
Assuming Hypothesis B to be correct, which of the following endocrine disorders would cause hypertension that could NOT be rectified by physiologically normal kidneys? A. an excess of aldosterone B. excess of glucagon C. shortage of thyroxine D. shortage of insulin
the only thing that would really increase blood pressure causing hypertension is aldosterone, which is made by the adrenal cortex --kidneys can't do any type of negative feedback to inhibit aldosterone secretion The correct answer is A. Aldosterone is a hormone released by the adrenal glands. Physiologically normal kidneys respond to aldosterone by increasing the reabsorption of both sodium and water. This leads to an increase in blood volume and therefore blood pressure. Thus, A is the best answer. Iodine is an element that plays a key role in the function of thyroxine (T4), a thyroid hormone. There are two main types of thyroid hormones: T3 and T4 (or thyroxine). Both hormones contain iodine atoms (T3 contains three and T4 contains four) and both are essential in order to maintain basal metabolic rate.
Why do eukaryotes have increased specialization?
this is because of compartmentalization... organelles in eukaryote cells are more spread out so they work more efficiently specialization explains why cells become eyes or livers or fingers
tidal volume vs dead space
tidal volume is the air you breathe in and out & dead space is the amount of air that is present in the alveoli so if TV is 400 and dead space is 100 then only 300 is able to reach the lung because the dead space blocks out 100, so only 300 can take part in gas exchange
what is pharyngeal tissue referring to?
tissue of the pharynx
*** why do we shiver when we're cold?
to increase (or create) body heat think about body rubbing together like sticks to make fire
because viruses lack metabolic machinery of their own to generate energy or to synthesize proteins-- they depend on host cells to carry out these vital functions... so we call them ___?
viruses are called obligate intracellular parasites
do eukaryotes have a phospholipid bilayer?
BOTH PROKARYOTES AND EUKARYOTES HAVE A PHOSPHOLIPID BILAYER
what can secrete gastric lipase?
chief cells as well as making pepsinogen
what does a big part of membrane fluidity come from?
cholesterol: @ HT = less fluid @ LT = more fluid length of FA chain: longer = less fluid shorter = more fluid
would cis or trans FAs have more of a kink?
cis would have more of a kink than trans.... so cis FA have more membrane fluidity than trans
what are coding vs noncoding RNA?
coding: mRNA which forms proteins (translation) noncoding: rRNA: form ribosomes tRNA: help transfer AA to A site of ribosomes- pair mRNA codon with specific AA snRNA (small nuclear): binds to SRNPs siRNA and miRNA --> they both do RNA interference and binds complementary mRNA siRNA (small interfering)- bind and trigger degradation miRNA (micro)- silence gene expression --> marks for degradation or blocks translation
what are salt bridges or electrostatic interactions made up of?
combine elements of both H-bonding and ionic bonding between opposite charge molecules
what are nuclear localization sequences?
they are signals sent to the protein (such as transcription factors) that tell the protein to go to the nucleus
insulin sensitivity vs insulin resistance
Insulin sensitivity means that with a small amount of insulin, blood glucose levels would begin to decrease insulin resistance -- caused when cells are overexposed to insulin so you need LOTTTS on insulin to elicit same effects so HIGH blood insulin levels and also high blood glucose levels because even though insulin is being produced, its still not going into the cell at the same rate
Mendelian vs nonmendelian inheritance
Mendalian: the basic principles associated with the transmission of genetic material, forming the basis of genetics, including the law of segregation and the law of independent assortment Autosomal inheritance Non mendalian: -triplet repeats -genomic imprinting -mitochondrial -multifactorial inheritance of multiple allele traits, traits with codominance or incomplete dominance, and polygenic traits
Bile helps out which organ
a bitter greenish-brown alkaline fluid that aids digestion OF THE SMALL INTESTINE and is secreted by the liver and stored in the gallbladder.
What is inclusive fitness?
a measure of an organism's evolutionary success in the population it is direct (own reproduction) + indirect fitness (cooperative behavior which allows an increase in the population of the organisms' own species)
what are the conservation substitutions by amino acids?
aliphatic -->VAL GI amide containing --> Q & N hydroxyl --> S & T basic --> R & K acidic --> E & D aromatic --> F & T
What are peptide hormones?
all anterior pituitary hormones: FSH, LH, GH, Prolactin, ACTH, TSH, endorphins all hypothalamic hormones: GnRH, GHRH, Dopamine, CRH, TRH parathyroid: PTH pancreas: insulin, glucagon, somatostatin (GH inhibiting hormone)
what kind of signaling do the cells of the pancreas do?
alpha cells (inhibit beta) and beta (inhibit alpha) cells do PARACRINE signaling Delta cells inhibit beta and alpha via somatostatin and can inhibit digestion the alpha, beta, delta cells also do ENDOCRINE signaling because the release things into the bloodstream the acinar cells do EXOCRINE signaling bc they release pancreatic juice (bicarbonate rich juice filled with enzymes) into the pancreatic duct and that then goes into the duodenum of the small intestine
How does GPCR signaling work?
alpha subunit is activated by GTP which goes and binds to either: adenylate cyclase which turns ATP into cAMP and cAMP goes and activates PKA which causes other processes to activate OR PLC (phospholipase C) which hydrolyzes PIP2 into IP3 and DAG IP3 goes from cell membrane to ER + mitochondria and opens Ca2+ channels which releases Ca2+ in the cytoplasm ***Ca2+ goes and activates (binds to) PKC (protein kinase C) which phosphorylates intracellular proteins (DAG can directly diffuse into the membrane and activate PKC)
why do some cells become epithelial cells while others become muscle cells?
although cells have the SAME DNA -- specific genes are turned on and off, forming specific cells cell specialization
what enzyme activates trna?
aminoacyl-trna synthetase addition of ATP and AA trna has a proofreading site
what proteins are involved with alzheimers?
amyloid B proteins --> amyloid plaques tau proteins --> tangles
PPP is important for:
nucleotide synthesis and NADPH
What is incomplete dominance?
A blending of traits. Red+White=Pink. when one allele is not completely dominant over the other ex. GG (red) and gg (white) mix and make Gg and instead of being red... it is pink which is a mix of the two
are the metabolic processes in the mitochondria aerobic and anaerobic?
AEORBIC --> PDH, CAC, ETC
what do kinases use to phosphorylate?
ATP or GTP
What is an autosome? somatic cell vs gamete?
Any chromosome that is not a sex chromosome An autosome is any of the chromosome not considered as a sex chromosome. In humans, a somatic cell will normally contain 23 pairs of chromosomes (total=46 chromosomes). ... Twenty-two (22) of these pairs will be autosomes, and only one of them will be a pair of sex chromosomes (the X and Y chromosomes). somatic cells will have 2n (46 chromosomes) while gametes will have n (23 chromosomes)
Nitorgenous bases vs nucleoside vs nucleotides
BASES: adenine, thymine, uracil, guanine, cytosine nucleoSIDES: adenosine guanosine thymidine uridine cytidine--> sugar and base only nucleoTIDES: adenylic acid, guanylic acid, uridylic acid, cytidylic acid --> base + sugar + phosphate
What are the water soluble vitamins?
B vitamins and vitamin C
How are B cells activated?
By cell-to-cell contact with Helper T-cells, and by direct contact with a pathogen. Cell-to-cell contact and pathogen activation is very selective; the B-cell must express a receptor that matches a specific antigen detected by the Helper T-cells, or it must match a specific antigen on the pathogen. helper T cells release cytokines which activate the B cells
what germ layer leads to CT?
CT = bone, tendons, ligaments, blood vessels, blood so mesoderm (skeletal and cardiac and smooth)
what does RNA hybridize with?
DNA AND RNA
Each embryonic cell receives ____ set of genes and ___ helps determine differentiation
Each embryonic cell receives a complete set of genes and cell position helps determine differentiation After meiosis, human germ cells contain half the genetic material of other cells in the body, but they still retain one copy of each gene. The normal complement of genes is re-established at fertilization, before development of the embryo begins. Cell position does have an effect on development in humans.
how can the rate constant (k) be altered?
Enzymes or chaperones (protein folding) can either increase or decreasing the rate constant (k)
If an artery that supplies blood to a lung lobe was blocked but ventilation to the lobe was unaffected, how would alveolar gas partial pressures change? -would PO2 increase or decrease? would PCO2 increase or decrease? or both increase or both decrease?
If the blood flow to an alveolus were blocked there would be no flow of hemoglobin-rich red blood cells to take away O2 and no influx of CO2from the blood. As a result the air in the alveolus would become more like that of the atmosphere. It would acquire a higher PO2 and a lower PCO2. The correct answer is choice C and the other answers are incorrect because they contradict C.
sense (or coding) vs antisense (template) strand
In double-stranded DNA, only one strand codes for the RNA that is translated into protein. This DNA strand is referred to as the antisense strand. The strand that does not code for RNA is called the sense strand.
zymogens (proenzymes)
Inactive precursors of enzymes or other proteins that acquire full activity by specific cleavage of one or more peptide bonds of the protein need some sort of proteolytic cleavage to become active are inactive so they won't do anything
how do organisms evolve?
Individual organisms don't evolve. Populations evolve. Because individuals in a population vary, some in the population are better able to survive and reproduce given a particular set of environmental conditions. These individuals generally survive and produce more offspring, thus passing their advantageous traits on to the next generation. Over time, the population changes.
What is Kd vs Ka?
Kd is the dissociation constant --> likelihood the ligand can unbind the substrate Ka = association constant LOW Kd (& high Ka) = HIGH AFFINITY
do irreversible reactions have a small or large delta g?
LARGGGGE DELTA G
what are the branched alkyl AAs?
Leucine Isoleucine Valine
Lock & Key vs. Induced Fit Model
Lock & Key is when the enzyme already matches the substrate shape-- requires NO ENERGY, just fits Induced Fit model is when the binding of the substrate induces the enzyme to change its shape -- REQUIRES ENERGY to change active site to undergo conformational change
how are the glial cells made and how?
Neural tube --> makes CNS + CNS glial cells: oligodendrocytes, astrocytes (BBB + nourish), ependymal (CSF + ventricles/barriers) cells, and microglia neural crest cells make PNS + PNS glial cells: schwann cells (like oligodendrocytes) & satellite cells (support cell bodies like astrocytes but for PNS)
where are antigens located?
ON THE OUTSIDE OF THINGS -- EXTERIOR OF CELLS that is why antibodies bind to the outside this is why for NS exam it asked why a vaccine cant be used for something that is inside of the cell.. if all of the cells have this thing in them and it isn't brought to the surface then antibodies aren't going to be able to bind to them so you cant use a vaccine against them antibodies are super big... they're not gonna just go through the cell membrane aka phospholipid bilayer
What determines if a species is the same or separate?
One of the key factors that determines a species is: the ability to successfully breed and produce fertile offspring. Two organisms that do not meet this criteria are considered separate species so if species dont interbreed (breeding with different species) and can make fertile offspring then they are separate species
Y-linked inheritance
Only males have Y chromosomes, passed from fathers to sons, all Y-linked traits are expressed fathers ALWAYS pass it to sons
"colchicine, an inhibitor of microtubule reorganization" Colchicine most likely relieves gout symptoms through what mechanism? A. Prevention of uric acid diffusion through cell membranes B. Inhibition of leukocyte phagocytosis of uric acid crystals C. Inhibition of uric acid crystal formation D. Maintenance of the pH optimum for PRPP synthetase
Phagocytosis requires that the cell change shape dramatically as it surrounds and engulfs large extracellular particles. Microtubules are one of the cytoskeletal elements that help determine cell shape. This function relies on the ability of the microtubules to disassemble and reorganize. The drug colchicine inhibits microtubule reorganization and would therefore inhibit phagocytosis of uric acid crystals by leukocytes. Thus, B is the best answer.
What are the professional antigen presenting cells?
Professional antigen presenting cells (APC), i.e., dendritic cells (DC), monocytes/macrophages, and B lymphocytes, are critically important in the recognition of an invading pathogen and presentation of antigens to the T cell-mediated arm of immunity. MHC class II -- bind helper T cells
what are epitopes?
Sites on an antigen that are recognized by the immune system as nonself part of an antigen molecule to which an antibody attaches itself
Of the following tissues, which is NOT derived from embryonic mesoderm? A. Circulatory B. Bone C. Dermal D. Nerve
Solution: The correct answer is D. The question asks the examinee to identify the tissue that is NOT of mesodermal origin. Of the tissues listed, the only one that does not arise from the mesoderm during embryonic development is nervous tissue (D). Nervous tissue arises developmentally from ectoderm, not mesoderm. Thus, D is the best answer. ecto, meso, and endo all make up layers of the skin which is dermal
"Structurally, the S ganglia appear near the spinal cord in the thoracic and lumbar regions and connect with each other to form the sympathetic trunk. PS innervation originates in either the brain stem or the sacral region of the spinal cord. The PS ganglia lie in or near the organs they connect to but do not connect with each other (Figure 1)." Based on information in the passage, would the S or the PS division of the ANS be expected to produce a more rapid systemic (whole-body) response to a stimulus? A. the S division, because its ganglia are interconnected B. S division because it secretes NE C. PS division because its ganglia are not innerconnected D. PS division because it seceretes acetylcholine
The correct answer is A. All of the answers presented are correct statements, but only one contains information consistent with a mechanism that would increase the speed of the systemic response to a stimulus. Multiple pathways to ganglia lead to more rapid response of the sympathetic system. Multiple pathways are also more consistent with a systemic, rather than localized, response. The type of neurotransmitter involved is irrelevant and the fact that the parasympathetic ganglia are not interconnected is a reason to reject the choices which refer to that system. Thus, answer choice A is the best answer.
An ulcer that penetrated the wall of the intestine would allow the contents of the gastrointestinal tract to enter: A. perineum B. peritoneal cavity C. pleural cavity D. lumen of intestine
The correct answer is B. If an ulcer penetrated the walls of the intestine, this would allow the contents of the gastrointestinal tract to enter the peritoneal cavity. Membranes surround this cavity, which would prevent further transport of the gastrointestinal contents through the rest of the body. An ulcer in the small intestine would not allow the contents to enter the lumen because this is the normal place in which the contents are found. perineum - the area between the anus and the scrotum or vulva
"After its release, NE in the synaptic cleft is inactivated primarily by active transport back into the nerve terminal (Figure 1), where it is either broken down by monoamine oxidase (MAO) or sequestered into vesicles. Any NE not taken up is broken down by catechol-O-methyltransferase (COMT)." A compound that inhibits monoamine oxidase (MAO) should have which of the following effects on NE concentration? A. increase the extraneuronal NE concentration B. increase the intraneuronal NE concentration C. decrease the intraneuronal NE concentration D. decrease the extraneuronal NE concentration
The correct answer is B. The question asks the examinee to identify the most likely effect that an inhibitor of monoamine oxidase (MAO) would have on the concentration of NE. According to the passage, NE is actively transported back into the presynaptic nerve terminal where it is either sequestered into vesicles or broken down by MAO, an intraneuronal enzyme. Inhibiting MAO would prevent the breakdown of NE within the neuron, leaving a greater amount of NE to be stored in vesicles, resulting in an increase in the intraneuronal NE concentration (B). Thus, B is the best answer.
The concentration of the protein cyclin rises and falls during the cell cycle as shown in Figure 1. Figure one caption: Changes in the concentration of cyclin during phases of the cell cycle What mechanism could account for this oscillation of cyclin protein concentration? A. Replication of the cyclin gene during S phase of interphase B. Segregation of chromosomes carrying the cyclin genes during mitosis C. Translation of cyclin mRNA in interphase and proteolysis of cyclin protein in mitosis D. Translation of cyclin mRNA in mitosis and proteolysis of cyclin protein in interphase
The correct answer is C. The graph shown in the question indicates that the concentration of cyclin rises and falls in a regular manner throughout the cell cycle, reaching a peak just at the beginning of mitosis, gradually declining during mitosis, reaching a minimum at the end of mitosis, and gradually increasing during interphase. The mechanism that can best account for this oscillation in the concentration of cyclin is translation of cyclin mRNA (creating the protein from mRNA template) followed by proteolysis (destruction) of cyclin protein during mitosis.
What process would be most disrupted by an inflammation of the colon? A. digestion B. absorption of nutrients C. absorption of water D. secretion of digestive enzymes
The correct answer is C. The passage presents information about inflammatory bowel disease, including Chron's disease and ulcerative colitis, the latter of which is associated with inflammation of the colon. The item asks what process would be most disrupted by an inflammation in the colon. Since the primary process that takes place in the colon is absorption of water, then the absorption of water is the most likely process to be disrupted.
Bicarbonate ions in the blood and the dialysate are important for maintaining physiological levels of: A. water B. chloride C. hydrogen ions D. glucose
The correct answer is C. The question asks the examinee to identify the role of bicarbonate ions in maintaining physiological levels of some feature of the blood. Bicarbonate ions maintain proper physiological pH, or the level of hydrogen ions (C). A, B, and D are incorrect because bicarbonate ions do not help maintain proper levels of water, chloride, or glucose. Thus, C is the best answer.
The ciliate protozoan Tetrahymena contains two nuclei: a diploid, germ-line micronucleus and a 45-ploid macronucleus that is the site of gene expression during the vegetative state. In a mating of two Tetrahymena strains that are homozygous in their macronuclei and heterozygous in their micronuclei for a recessive gene, what percentage of the F1 generation will express the recessive phenotype? 0% 25% 50% 100%
The macronuclei do not participate in mating so only the genotypes of the micronuclei need to be considered. If we call the recessive gene rand its dominant allele R, then a cross between two heterozygote strains Rr will produce the genotypes RR:Rr:rr in a ration of 1:2:1. The recessive gene will be masked so that its expression will not be observable if a dominant gene is present in the genotype. Only in the double recessive (rr) case will the presence of the recessive gene be observed. The answer then is that on the average 25% of the offspring will demonstrate the recessive phenotype (choice B).
The pancreas produces which of the following substances for the digestive system? A. bile salts B. emulsifiers C. gastric juices D. proteolytic enzymes
The pancreas produces several proteolytic enzymes, which are released into the small intestine where they are converted to their active forms of trypsin, chymotrypsin, and carboxypeptidase. Thus, D is the best answer
"blood pressure (P), flow rate of blood from the heart (cardiac output or CO), and vascular resistance to the flow of blood (VR): P = CO × VR" If blood pressure doubled and the resistance to blood flow increased by 50%, the amount of blood pumped by the heart would have: A. increased by 1/3 B. increased by 1/2 C. decreased by 1/3 D. decreased by 1/2
The passage states that P = CO × VR. Solving the equation for cardiac output (CO) and letting the original CO equal P/VR the new CO would then equal 2P/[(3/2)VR]. Reducing this equation shows that the new CO is the old CO, or an increase of . Thus, A is the best answer. 4/3 = 1.33% so increase by 1/3 of the original an increase by 50% --> 1.5% 1.5 = 3/2
When viewing an X ray of the bones of a leg, a doctor can tell if the patient is a growing child, because the X ray shows: A. cartilaginous areas in the long bones B. bone cells that are actively dividing C. presence of haversion cells D. shorter-than-average bones
The question asks the examinee to identify the characteristic that differentiates growing, developing long bones from adult bones. Long bones grow via endochondral ossification, which requires cartilaginous growth plates at the ends of long bones, that thicken as cartilage and later become ossified (A). Dividing bone cells (B) and haversion canals (C) can be present in fully ossified adult bones. Some adults who are short in stature may have fully ossified long bones that are shorter than those of a developing child (D). Thus, A is the best answer.
Which of the following describes a primary function of the myelin sheath? A. provides nutrients to motor neurons B. regulates synaptic vesicle discharge C. guides dendrite growth and branching D. increases the rate of conduction of action potentials
The question asks the examinee to identify a primary function of the myelin sheath. The myelin sheath is a fatty layer surrounding the long axons of neurons in vertebrates. A primary function of this layer is to enable nerve impulses (action potentials) to travel more quickly by jumping from node to node rather than traveling continuously along the entire length of the neuron. This supports D, which states that the myelin sheath increases the rate of conduction of action potentials. A, B, and C are incorrect because they describe roles that the myelin sheath does not provide. Thus, D is the best answer.
Which of the following tissues have cells that are in direct contact with the external environment or elements of the external environment? I. The lining of the reproductive tract II. The lining of the respiratory tract III. The lining of the gastrointestinal tract
The question asks the examinee to identify those tissues that are in direct contact with the external environment or elements of the external environment. Tissues that are exposed to the external environment have mucosal membranes. All of the tissues listed contain an element of mucosa (e.g., the nasal cavity, vagina and anus -- stomach). Thus, D is the best answer.
Radioactively labeled uracil is added to a culture of actively dividing mammalian cells. In which of the following cell structures will the uracil be incorporated? A. chromosomes B. ribosomes C. lysosomes D. nuclear membrane
The question asks the examinee to predict the cell structure in which radioactively labeled uracil will become incorporated if added to a culture of actively dividing mammalian cells. Uracil is a component of RNA. Therefore, one would expect to find the radioactively labeled uracil in cell structures that contain RNA. B is the best answer because ribosomes contain rRNA and proteins. A is incorrect because chromosomes, by definition, consist primarily of proteins and DNA. Although DNA is composed of nucleic acids, DNA contains thymine instead of uracil. C and D are incorrect because RNA is not an integral component of either lysosomes (C) or the nuclear membrane (D). Thus, B is the best answer.
What is the roles of the proteins actin and myosin during muscular contraction?
The sliding filament model describes the interaction of actin and myosin during muscle contraction. According to this model, neuronal impulses cause the release of calcium from the sarcoplasmic reticulum within muscle cells. The calcium then binds to troponin, a molecule that along with tropomyosin, blocks the binding sites for myosin on actin molecules. Calcium binding to troponin causes a shift in the troponin/tropomyosin complex, revealing the binding site for myosin. Myosin then binds to actin, causing a conformational change in myosin that "cocks" the head of the myosin molecule and slides the actin filament relative to myosin. ATP binds to myosin, causing it to detach from actin and "recharge" (rebend again). If another binding site is available on actin, myosin will bind again, and slide the actin filament even further. Thus, D is the best answer. D- bridges between actin and mysoin form, break, and reform, leading to the shortening of muscle sarcomeres
if we are told that a reaction is kinetically stable... what does this tell us about the reaction?
The slower the reaction occurs, the greater the kinetic stability. If you say, "This reaction is kinetically stable," then that implies that the reaction occurs very slowly. Thermodynamicstability depends on whether or not the reaction is spontaneous. This depends on the change in free energy (ΔG). even if we are told the a reaction if thermodynamically favorable in reverse (+ΔG) but it is slow, then it is still thermodynamically unstable because it is prone to break **slow rxn= kinetically stable**
Tests performed on the M. tuberculosis strain infecting the patient's coworker indicated that the strain was susceptible to both ampicillin and kanamycin, and the coworker was successfully treated. The M. tuberculosismost likely survived in the patient because it had: A. undergone conjugation with cells of resistant E coli B. undergone an antibiotic-induced mutation that conferred antibiotic resistance C. reproduced more rapidly than the strain in the coworker D. adapted to its new environment by modifying its metabolism
The strain of M. tuberculosis in the coworkers was killed by both ampicillin and kanamycin, indicating that this strain did not carry a plasmid gene that made it resistant to these two antibiotics. However, once the M. tuberculosis coexisted in the patient with other antibiotic-resistant bacteria, the M. tuberculosiscould survive despite treatment with large doses of these two antibiotics. The antibiotic does not induce mutations; the few cells that are already resistant flourish in the absence of the nonresistant bacteria. The M. tuberculosis did not adapt to its new environment by modifying its metabolism; rather, there was a strain with a metabolic capability that was not compromised by the antibiotic. The passage indicates that conjugation may occur between members of different bacterial species. Therefore, it is most likely that these M. tuberculosis bacteria underwent conjugation with resistant cells, answer choice A.
The outer layers of human skin are composed of dead cells impregnated with keratin and oil, which make the epidermis relatively impermeable to water, yet humans sweat freely in hot temperatures. This occurs because:
The sweat glands secrete onto the surface of the skin through channels continuous with the most superficial layer of the skin, the epidermis. These channels prevent water loss by isolating the water-permeable, sweat-secreting cells from dry surface air. The openings of the sweat glands on to the surface of the epidermis are pores. The correct answer is B. All the other answers require some movement of water through the epidermis itself, which is relatively impermeable.
role of ligase
This enzyme brings together the Okazaki fragments brings DNA together brings 2 things together lyase --> breaks thing into 2
Q states that without Hip1, the knockout bacteria can cleave WKLL-ACC but no CSL substate. Why?
This is because CSL had a high specificity for Hip1 and substrates that have a high specificity for one enzyme may have a low specificity for another WKLL-ACC is probably still cleaved because it has a high specificity for another enzyme
Virus vs Viroid vs Prion genetic material proteins or no enveloped host
Virus: DNA,RNA,ss,ds proteins enveloped/capsid plants, animals, bacteria Viroid: ssDNA (circular) no proteins not enveloped plants Prion: no genetic material made up of a protein (misfolded) not enveloped mammals
What are the fat soluble vitamins?
Vitamins A, D, E, K
do viruses have enzymes?
YES they all have at least one like how retroviruses have reverse transcriptase so they can form dna
Does DNA have a 1:1 ratio?
Yes, according to watson and crick's model... the # of A= # of T and the # of G = # of C 1:1 ratio
what does a thicker band mean in relation to Kd?
a thicker band means that more binding occurred so it must mean there was a lower Kd (increased binding affinity)
What is the net volume of fresh air that enters the alveoli each minute, assuming that the breathing rate is 10 breaths/min, the tidal volume is 800 mL/breath, and the nonalveolar respiratory system volume (dead space) is 150 mL? A. 65 mL B. 95 mL C. 6500 mL D. 7850 mL
a. 6500 mL i. The amount of air entering the lungs in a single breath, or tidal volume, is given as 800 mL/breath. Of that 800 mL only 650 mL reaches the alveoli per breath (800 mL of air inhaled minus 150 mL of nonalveolar respiratory volume). Therefore the net volume of air that reaches the alveoli each minute is equal to 650 mL/breath multiplied by 10 breaths/min, or 6500 mL. Thus, C is the best answer.
with the induced fit model, what causes the active site to change?
active site changes shape when a substrate binds, which increases flexibility active site goes from relaxed to induced back to relaxed
What are steroid hormones?
adrenal cortex: cortisol, aldosterone gonads: estrogen, progesterone, testosterone
How do RBCs make ATP?
anaerobic glycolysis because they lack organelles they cant use mitochondria to produce ATP so they must rely on glycolysis In RBCs, which lack mitochondria and oxidative metabolism, pyruvate is reduced to lactic acid, a three-carbon hydroxyacid, the product of anaerobic glycolysis. Each mole of glucose yields 2 moles of lactate, which are then excreted into blood.
how does women's body change during menopause?
anxiety, irritated breast atrophy infertility increased osteoclast activity- decreased bone density -- bone loss = osteoporosis women already have smaller bone density to begin with because women are smaller than men
Out of arteries, veins, and capillaries, which is the best regulator of BP?
arteries can actively vasodilator and vasoconstrict so they can easily regulate BP veins can also do this but not as well as arteries can capillaries cannot do vasodilation or vasoconstriction***
Where is BP the highest?
arteries>capillaries>veins HIGHEST AT ARTERIES LOWEST AT VEINS
What happens to affinity as Km increases?
as Km increases, affinity decreases because if you need more substrates to get to Km, the substrates must not have a high affinity for the enzyme
nuclear membrane vs nuclear envelope
basically the same thing but membrane is just talking about the double layer of the nucleus that has the ER coming off of it (extends from outer membrane) the nuclear envelope is talking about the nuclear membrane AND includes the nuclear pores
if oligonucleotides such as mRNA were not degraded rapidly by intracellular agents, which of the following processes would be most affected? a. the production of tRNA in the nucleus b. the coordination of cell differentiation during development c. the diffusion of respiratory gases across the cell membrane d. the replication of DNA in the nucleus
b why? destruction of mRNA prevents continuous protein production, allowing the cell to change its protein expression over time. Coordination of cell differentiation during development is extremely sensitive to the timing of mRNA turnover not a or d? exact timing of mRNA turnover is less critical to the successful completion of tRNA production and DNA replication not c? unlikely that an accumulation of mRNA would affect the diffusion of respiratory gases across the cell membrane AAMC: The correct answer is B. The question asks the examinee to identify the process most likely to be affected if oligonucleotides, such as mRNA, were not degraded rapidly by intracellular agents. The destruction of mRNA prevents continuous protein production, allowing the cell to change its protein expression over time. B is the best answer because the coordination of cell differentiation during development is extremely sensitive to the timing of mRNA turnover. A and D are not the best answers because the exact timing of mRNA turnover is less critical to the successful completion of tRNA production (A) and DNA replication (D). C is incorrect because it is unlikely that an accumulation of mRNA would affect the diffusion of respiratory gases across the cell membrane. Thus, B is the best answer.
what happens to the bicarbonate buffer system when bicarbonate excretion occurs?
because bicarbonate is decreasing, there would be a right shift of the curve which increases H+ so pH decreases when we are getting rid of bicarbonate it is probably bc pH is too basic so we would want to increase H+ to make pH more acidic
Why would blocking the veins increase interstitial fluid?
because blood travels from Arteries --> caps --> vein and blocking the veins causes back flow so fluid runs to caps which causes build up of fluid so hella fluid gets pushed out of the caps and into the interstitial space via hydrostatic pressure
why would you use western blot for histone acetylation?
because it is a post translational modification -- modification of proteins so western
why can't lytic cycles form tumors?
because lytic cycles just create viruses and kill cells lysogenic cycles can do rapid cell division with the virus (dormant) inside -- cells just keep duplicating with the infected cell with the virus which can make neoplasm or tumor
what germ layer makes melanocytes?
because melanocytes contribute to the skin... it would have to be ectoderm
How can axons do long distance communication between neurons?
because of white matter --> afferent axons carry sensory information to the brain and efferent axons carry motor commands to the body via white matter of the spinal cord white matter = axons --> send info gray matter = interneurons, dendrites, soma - process info
how can we turn cysteine and serine into good nucleophiles?
by deprotonating them with a base! by removing the OH from serine and the SH from cysteine we are able to give them a negative charge which creates a good nucleophile
how does a cation exchange work?
cation exchange attracts cations so it is lined with negatively charged ions
If Anolis lizards have X-Y chromosomal sex determination, the locus of a gene for the UV reflectance pigment:
could be on a sex chromosome or an autosome Based on the information presented, the gene encoding UV-reflectance pigment could be on a sex chromosome or an autosome. The fact that the pigment is expressed in the dewlap, a structure found only in males, is not sufficient to eliminate any chromosome as the location of this gene. Thus, D is the best answer.
The chemical gramicidin inserts into membranes and creates an artificial pathway for proton movement. if mitochondria are treated with gramicidin, what will happen to the rate of ATP synthesis?
decrease because the proton gradient will rapidly reach equilibrium The correct answer is C. Hydrogen ions (H+) are protons. The provision of a channel for proton flow across the membrane would allow hydrogen ions to flow across the membrane until equilibrium had been achieved between the concentrations on each side of the membrane. Because ATP synthesis is driven by a flow of hydrogen ions down a concentration gradient, ATP production will decrease and eventually stop as equilibrium is established (not increase as suggested in answer choice A or remain unchanged as suggested in answer choice D). The decrease has nothing to do with the rate of hydrogen ion donation by NADH, answer choice B. Answer choice C is the correct answer.
What do bottlenecks do?
decrease genetic diversity and decrease allele frequency in a random way caused by environmental catastrophe that kills a big chunk of a population
alveoli's main role
diffusion of gases --> CO2 & O2
what is the splice donor and acceptor sites?
donor site- between 5' exon and intron acceptor site- between intron and 3' exon
what germ layer makes CNS and nerves?
ectoderm because the neural tube (ectoderm) forms the CNS
How is NADH regenerated?
either through ETC in mitochondria or via fermentation in the cytosol
what germ layer makes the pancreas?
endoderm endoderm line digestive and respiratory tracts AND make accessory organs like liver, gallbladder, and pancreas
endothelial vs epithelial cells
endothelial cells --> line the blood vessels epithelial cells --> line the outer surface of the body (skin) and line the organs
environmental factors determine ________ positions of cells determine ___________
environmental factors determine cell differentiation and gene experession ex. temperature can lead to turtles giving birth to a specific gender the position of cells (where cells are located) determine what the cells turn into (or make) ex. the hand starts as a nub and then the cells where the thumb would be start making the thumb because they are located there and the cells in between the fingers die (apoptosis- sculpting)
What is Vmax proportional to?
enzyme concentration and Kcat (because enzyme is operating at maximum velocity)
What are reactive oxygen species (ROS) and what can we use to stop them?
free radicals or peroxisome byproducts which cause oxidative damage --> they can cause lead to abnormal apoptosis which is what cause malformations in babies and can cause cancer and cell damage we can use antioxidants to stop them trap ROS and make them less reactive
where does the extra lymph fluid go from the capillaries?
from capillaries into interstitial space as interstitial fluid to lymphatic capillaries to lymphatic vessels to thoracic duct to subclavian vein to the heart
How does ammonia in urine form?
from the AMINE backbone of AAs (deAMINation) or from the amide of asparagine and glutamine (deAMIDation)
what can we do after PCR?
gel electrophoresis
"Excessive sweating may upset homeostasis by impairing water and salt regulation. During dehydration, the kidneys may reduce their urinary output from the normal level of 1.0-1.5 L H2O/day to as little as 0.5 L H2O/day, and renal salt excretion may decline to near zero. Excessive sweating also reduces the volume of blood available for delivering O2 to the internal body tissues." Kidney failure during severe dehydration is most likely due to: a. inadequate blood volume for effective filtration. b. inability to produce sufficient urine. c. buildup of salts in the distal tubules. d. increased body temperature.
got right- GTK The correct answer is A. This question asks the examinee to identify the cause of kidney failure during times of extreme dehydration. As the passage states, severe dehydration greatly reduces the volume of filtrate moving through the nephrons of the kidney. If fluid volume is too drastically reduced, the kidney will be unable to effectively do its job of filtering and maintaining homeostasis within bodily fluids. Thus, A is the best answer.
The posttranslational modification of some of the eukaryotic cell's most abundant proteins is thought to affect the ability of those proteins to condense DNA into 30‑nm fibers. Given this, these proteins are most likely: a. tubulins b. histones c. transcription activators d. dna polymerase subunits
got right- good to know Histones are among the most abundant proteins in eukaryotic cells. These small, basic proteins come together with DNA to form nucleosomes, the bead-like, primary structural elements of chromatin. Interactions among histone proteins in separate nucleosomes allow those nucleosomes to form the highly compacted 30-nm chromatin fibers. Posttranslational modifications that alter the charge on histone proteins affect their ability to condense DNA. Thus, B is the best answer.
what is a nutrient broth?
grows bacteria broth like bone and chicken broth but it grows bacteria
what is it when pH=pKa
half equilibrium point it is when the ratio of deprotonated to protonated is 1:1 which is why we can simplify the H-H equation to pH=pka
what happens to proteins that have a signal peptide vs ones that lack one?
have signal peptide: go the rough ER and protein secreted into the lumen of the rough ER --> travels to golgi --> SECRETORY PATHWAY secreted out of the cell, integrated into plasma membrane (like transmembrane proteins) or sent to lysosomes NO signal peptide: stay in cytosol -- proteins undergo post translational modifications, sent to mitochondria, peroxisome, nucleus, chloroplast etc
what is does it mean if there are antibodies against proteins?
immune system is targeting those proteins for degradation
Control of heart rate, muscle coordination, and appetite are controlled by which areas of the brain? (3 separate structures)
heart rate- brain stem muscle coordination- cerebellum appetite- hypothalamus
what is the role of intestinal proteins?
help breakdown and absorb nutrients -structural proteins -digestive enzymes -transport nutrients
what are the structural lipids?
hydrolizable glycerophospholipds and sphingolipids nonhydrolizable cholesterol
if you see a bunch of O and N atoms, it is hydrophobic or philic?
hydrophilic
what is most likely to be seen at the surface of globular domains?
hydrophilic, polar, charged are always on the surface of proteins hydrophobic is on the inside
Do noncooperative enzymes have one or more active sites?
if enzymes are noncooperative, they can still have more than one active site but it is not required like cooperative enzymes
what happens if a virus gets mutated in its viral genome?
if mutation happens in the right spot the virus becomes virulent or it becomes nonfunctional
what can we tell about the AA sequence of a proteins depending on how they fold?
if proteins fold similarly then they have a similar AA sequence if proteins fold differently then they have a different AA sequence if proteins have different number of glycosylation sites then they undergo different post-translational modifications so they probably fold differently
what if there are issues with the urethral sphincters?
if the internal and external sphincters are unable to contract then pee will always be flowing out of you and you wouldn't be able to hold in your pee
once denatured the protein is _____
inactive
if there is increased parasympathetic activity, how could it lead to loose stools?
increased parasympathetic activity would mean increased peristalsis and digestion so things are moving through really quickly so there would be increased chyme moving through but because motility is also rapid, it does not leave time for the gut to reabsorb nutrients and water so they would also be excreted with the stool... less water reabsorption = watery stool
how can fight or flight response alter urine production?
increased urine production can be explained by an increased blood pressure caused by adrenaline, released in response to excitement or anxiety—the fight or flight response.
how does leptin affect FA synthesis?
increases FA oxidation and decreases FA synthesis
how can glycine be beneficial for secondary structures?
increases flexibility of beta turns
how does phosphorylating alter charge?
increases negative charge
what does proline do to secondary structures?
increases rigidity increases tight turns tendency to adopt cis conformation
leucocytes gravitate towards ___________
inflammation
hyperpolarization cause neurotransmitters lead to the influx and efflux of what ions?
influx of negative ions into the neuron efflux of positive ions out of the neuron the goal is to make the cell super negative inhibits AP
what can gut flora in the large intestine do?
it can break down (metabolized) undigested carbohydrates that are coming from the small intestine into turn them into fatty acids (glucose then FA) which can then be absorbed by the gut
what does it mean if a protein is a monomer?
it has one subunit! so we know that it is not a quaternary structure bc quaternary structures have multiple subunits
What is Tm in terms of DNA?
it is the melting temperature... midpoint of graph -- when 50% of the DNA is single stranded so equal amounts of single stranded and double stranded dna (or 50% of protein is unfolded so equal amounts of folded and unfolded proteins) 0%= double stranded 100%= single stranded the more G-C, the higher the Tm because the melting temperature is higher for triple bonds because stronger bonds HIGHER MELTING POINT MEANS: -more stable -stronger intermolecular forces -slower denaturation rate
what can we do with palmitic acid or palmitate once we make it?
it is the only FA that the cell itself makes it can be incorporated into the cell membrane it usually has a negative charge or a neutral charge
if there is a protein channel that wants Ca2+ to go through, what would the protein channel be made of?
it would be made of negative charges because opposites attract and it would want to attract the positive charge of the calcium to allow it to go through the channel
if a protein is negatively charged (deprotonated) where would it start with isoelectric focusing?
it would start out at the cathode side because it is deprotonated but it will be attracted to the anode side and want to move there stops migrating when charge = 0
what is the cardiac sphincter
juncture of esophagus and stomach (lower esophageal sphincter)
what secretes erythropoietin?
kidney
In comparison with the wall of the right ventricle of the heart, the left ventricular wall is: (thicker or thinner; generates higher or lower pressure when it contracts)
left ventricular wall is THICKER AND GENERATES HIGHER PRESSURE WHEN IT CONTRACTS The left ventricle pumps blood through the entire rest of the body. The difference in the size of the lung compared to the rest of the body suggests that the left ventricle develops more pressure and has a thicker wall than the right. The organs through which the left ventricle pumps blood are farther away from the heart than the lungs and resistance in a tube is inversely proportional to the length of the tube. This would also suggest a thicker wall for the left ventricle and greater pressure.
microarray vs southern blot
microarrays use hybridization to detect a specific DNA or RNA in a sample. But whereas a Southern blot uses a single probe to search a complex DNA mixture, a DNA microarray uses a million different probes, fixed on a solid surface, to probe such a mixture. microarrays have a bunch of wells with single stranded dna (probes that are fluorescently labeled) and using mRNA they do reverse transcriptase to make cDNA which is complimentary to the DNA in the wells this is important for cancer research because we are able to identify faulty genes (with deleted or extra dna and sequence it to see how the protein was altered to lead to cancer
what can you determine about the pI of molecules based on their charge at pH of 7.4: net positive charge = ? net negative charge = ?
net positive charge means that it is protonated so that means that pI>pH so that means in order to neutralize the molecule and make pH=pI, pI must be high and require high pH to neutralize net negative charge means that it is deprotonated so that means that pH>pI so that means in order to neutralize the molecule and make pH=pI, pI must be low and require low pH to neutralize
why cant glycine rotate plane polarized light?
only chiral molecules can rotate plane polarized light glycine is the only AA that is achiral
what is p & q in reference to dna?
p = short arms q = long arms during Robertsonian translocation, q combine
When is a p-value statistically significant?
p less than or equal to 0.05
what things can alter an enzyme's active site?
pH, temperature, and mutations like missense mutations induced fit theory
would something with a net positive or net negative sign have a higher pI and why?
pI>pH --> molecule is protonated so it would have a high pI meaning that it would need a higher pH in order to neutralize (or deprotonate)
what do morphogens do?
paracrine factors or signaling molecules that move along concentration gradients and help with cell differentiation signaling molecule dependent on concentration
perineum vs peritoneum vs peritoneal cavity
perineum- between anus and scrotum (males) or vulva (females) peritoneum- covers abdominal organs and abdominal walls peritoneal cavity- space between abdomen and organs like liver, stomach, intestines
how many FA do phospholipids have in comparison to sphinosines?
phospholipids = 2 FA sphinosines = 1
cell wall vs. cell membrane
plants, bacteria, and fungi have both a cell wall and a membrane (cell wall out and cell membrane inward) animal cells have only a cell membrane
what are the tissue of the lungs?
pleura and pulmonary
ploid vs diploid?
ploid is referring to haploid (n) diploid - 2n
what is the positive control and negative control related to?
positive control is related to IV because the independent variable is if the positive control is replicated --> because it is what you are expecting to see... want to create same results (or expected results) -- positive response negative control is related to the wild type -- if nothing was happening at all (no response or negative response)
For affinity columns, what would negatively charged things bind to?
positively charged things separates proteins based on non covalent binding interactions with antibodies or other ligands attached to column
primary vs secondary vs tertiary protein structures
primary- covalent peptide bonds (amide bonds- partial double bond character) secondary- H-bonding tertiary- van der waal forces, H-bonds, disulfide bonds, salt bridges aka ionic bonding aka electrostatic interactions aka between acidic and basic side chains like negative and positive charges, hydrophobic interactions when denaturation occurs, the primary structure continues to stay in tact -- amide bonds
size exclusion chromatography
relies on porous beads; larger molecules elute first because they are not trapped in small pores
How incubation help with inhibitors?
reversible inhibitors have non covalent interactions and can work faster than irreversible inhibitors which covalently bind and have covalent interactions incubation with reversible inhibitors won't make a difference because they already interact quickly so it won't speed up the inhibition process BUT with irreversible inhibitors, because they are slow... incubation gives the inhibitor more time to interact with the enzyme leading to increased inhibition
what is sera?
serum (of blood)
how does oxidative stress occur in the ETC?
so typically with oxidative phosphorylation, 1/2O2 + 2H+ + 2 e- --> 1 H2O (1 O2 + 4 H+ + 4 e- --> 2 H2O) but when there is not enough H+ or e-, oxidative damage occurs --- usually when there is a defect with complex V or one of the other complexes with O2 and only one e- --> O2- forms which is a superoxide with O2 and 2 e- and 2 H+, H2O2 forms which is hydrogen peroxide (need 4 H+ and 4 e- to form H2O) with 1/2O2 and 1 e- and 1 H+ --> OH radical forms (hydroxyl radical)
how do substrate concentration and Km relate at Vmax?
substrate concentration is significantly higher than Km at Vmax which is seen during saturation
is piloerection symp NS or parasympathetic?
symp NS you think of it like when someone is super cold, they feel like they need to survive (fight or flight) sweat glands- which help prevent us from overheating is also symp NS!! (the only gland that isn't parasympathetic)
what does isoprene form?
terpene
what are the gonads
testes and ovaries
what does colocalization hint at?
that means they are found in the same location so if protein X colocalizes with PDHC, which is in the mitochondria, then protein X most likely has a mitochondrial target signal that gets it there
if the passage is talking about mitochondrial DNA, what can we infer about the DNA?
the DNA is maternally inherited
Why is the promoter region so important with transcription? What is the transcription start site?
the promoter region has -35 and -10 elements and RNA polymerase 2 specifically binds to the -10 element aka the TATA box transcription factors help out with this because they go and bind to the TATA box and this causes RNA polymerase 2 to recognize and bind to the TF starts at +1 --> where first ribonucleotide is transcribed
all natural AAs are what conformation?
they are all L confirmation except glycine because it is chiral enzymes in our body exclusively work with L-AAs this is why when D-AAs are present, the enzymes are unable to do anything with them -- proteases are unable to degrade them all AAs are S-configuration except cytosine which is R and glycine which is achiral
"Experiment 1 Patients' sera were mixed with known pathogenic viruses and bacteria. A positive immunologic reaction was seen with a hantavirus that causes kidney disease." What was contained in the sera from the respiratory patients of Experiment 1 that caused the sera to react with a hantavirus that causes kidney disease? A. antibodies specific for the kidney disease hantavirus only B. antibodies to the unknown pathogen, which is antigenically related to the known hantavirus C. antibodies to kidney proteins D. the unknown pathogen
the patients participating in the experiment were inflicted with pulmonary disease NOT kidney disease -- so we can assume their immune system made antibodies to fight off the diease then when we mix a bunch of known viruses and bacteria with the sera, if one of those caused a reaction, then we know that it was because the hantavirus must have been super similar to the virus that causes pulmonary issues and that's why the antibodies made could go and attack the hantavirus producing an immune response -- the unknown pathogen's antibodies recognized the hantavirus, meaning that the hantavirus was antigenically similar to the unknown pathogen. The question asks the examinee to identify what component of the patients' sera caused the sera to react with a kidney disease-causing hantavirus in Experiment 1. Based on the passage, it can be concluded that these patients were infected with a pathogen that causes respiratory disease and is related to hantaviruses. In Experiment 1, antibodies specific for this pathogen in the patients' sera were causing antigens of a related kidney disease-causing hantavirus to immunoprecipitate. A is not the best answer because these antibodies were not specific for only the kidney disease-causing hantavirus; they were specific for the pulmonary disease-causing hantavirus as well. B is the best answer because the antibodies in the patients' sera were produced by the patients' immune system in response to the pulmonary disease-causing hantavirus. C is not correct because the passage does not present evidence that these antibodies were formed in response to kidney proteins. D is incorrect because the antibodies, not the pathogen against which these antibodies were formed, caused the immunoprecipitation. Thus, B is the best answer
What are diurnal rhythms?
the set point for hormone concentration in the blood changes as a function of time during day day time rhythm in physiological processes
what is morphology of bacteria?
the shape of bacteria (bacilli, spirilli, cocci)
how are Kcat and Km affected by enzyme concentration?
trick question!!!! they are not influenced by the concentration of anything they are constants!!! Km tells us the binding affinity of the enzyme Kcat tells us how many reactions the enzyme can catalyze per second at Vmax THEY ARE INTRINSIC PROPERTIES OF THE ENZYME THAT DONT ALTER BASED ON CONCENTRATION that is why catalytic efficiency (specificity constant) = Kcat/Km the reason Vmax is variable is that it can increase as enzyme concentration increases
What trisomies are viable?
trisomies 13, 18, 21 that means that there is an extra copy of chromosome 13, 18, or 21 they can survive past birth but do not live as long as other people and there are developmental issues that arise
True or false: Spontaneity can be either endothermic or exothermic.
true
what stop the cell cycle from proceeding?
tumor suppressor genes come in and stop the cell from going onto the next step... they want to stop cancer cells and make sure normal cell division occurs they can trigger/induce apoptosis
what AA helps make E/NE?
tyrosine
loading controls
ubiquitously expressed + have consistent concentrations across all cell/tissue types tell us the baseline cellular functions aka housekeeping gene --> consistently expressed throughout the cell ex. tubulin, actin, ubiquitin, G3PDH let us know that results were not due to outside things and that the IV actually caused the change
what is western vs southern vs northern blots?
western- detects proteins southern- detects dna northern- detects mrna
what is the process of making viral proteins when the virus carries DNA vs RNA for genetic info?
when DNA is present the transcription AND translation must occur with RNA, DNA can be directly made using ribosomes of the organism
what is the role of caspases?
when ROS forms leading to issues in development or DNA damage occurs it induces apoptosis this makes the mitochondrial membrane permeable so that cytochrome C can exit the cell Cyt C goes and activates caspases which further induce apoptosis by activating degradation pathways like proteolysis caspases are usually inactive in healthy cells
Can mutations be inherited?
yes --> mutations can be passed on from generation to generation
Which of the following organelles most resembles the Golgi apparatus when an intact eukaryotic cell is viewed under the electron microscope? A. nucleolus B. mitochondrion C. plasma membrane D. smooth endoplasmic reticulum
** The correct answer is D. The smooth endoplasmic reticulum most resembles the Golgi apparatus in an intact eukaryotic cell when viewed under the microscope. Both organelles appear to be membranes with many folds.
Parathyroid hormone, which acts on bone tissue to encourage the formation and activity of osteoclasts (which break down bone cells) and to impair new bone formation. Rickets affects children, causing inadequate mineralization of new bone matrix. The ratio of mineral to organic matter is lower than normal. This abnormality can result in distortion of the bones, especially long bones, leading to bowed legs. It is caused by insufficient vitamin D activity. Which of the following conditions could produce rickets? I. Metabolic deficiency of parathyroid hormone II. Impairment of conversion of vitamin D to its active form III. Inability of the active form of vitamin D to act on its target tissue
**missed passage info I thought bc PDH activates Vit D this would cause it.. but PDH breaks down bone so there would be a ratio of mineral to organic matter that is lower than normal -- which is seen in individuals with rickets. However, if there is a deficiency in PDH then that means there would be a higher mineral to organic matter ratio, which is the opp of what happens with rickets. The passage states that rickets is caused by insufficient vitamin D activity. Insufficient vitamin D activity would reduce the ability of the body to absorb ingested calcium from the small intestine. To maintain calcium levels in the blood plasma, parathyroid hormone would promote the breakdown of bone tissue, causing the bones to become weak. If there were a metabolic deficiency of parathyroid hormone, the body would be unable to break down bone tissue (option I), causing a higher than normal ratio of mineral to organic matter in the bones instead of a lower than normal ratio. However, if the body were unable to convert vitamin D to its active form, or if vitamin D were unable to act on its target tissue, overall vitamin D activity would be impaired (options II and III), which can lead to rickets. Thus, D is the best answer.
Isoelectric focusing
+ anode (attracts negatively charged) = at low pH - cathode (attracts positively charged) = at high pH pH>pI = deprotonated so AA has negative charge pI>pH = protonated so positive charge
+/-delta g for kinetic and thermodynamic rxns
+delta g = thermodynamically unstable and requires the input of energy via coupling (**most anabolic processes like DNA and protein synthesis usually require energy) -delta g = thermodynamically (and kinetically) stable and requires NO energy input
what causes a right shift?
- low pH (more acidic environment) -increased temp -increased PCO2 -increased 2,3-DPG all occur with increased metabolic activity in the tissue and the tissue requires more O2 PO2 in muscles does decrease because oxygen is being consumed but that does not cause the shape of the curve to change
"Experiment 1 Patients' sera were mixed with known pathogenic viruses and bacteria. A positive immunologic reaction was seen with a hantavirus that causes kidney disease. Experiment 2 Synthesized gene sequences from two known hantaviruses were mixed with nucleic acid from patients' lung tissues but not with lung tissue from control subjects. Hybridization between nucleic acid strands occurs when they base-pair with each other. Hybridizationoccurred between the synthesized genes and nucleic acid from the patients' lung tissues." Why did investigators conclude that the new pathogen is a hantavirus? A. the experiments showed that it is related to known hantavirus B. the experiments showed that it infects lung endothelium C. the patient data showed that the type of disease it caused resembles that caused by the known hantavirus D. no pathogenic bacteria were found in the lung samples from bacteria
-each of the experiments are showing how the hantavirus has similar qualities to the unknown pathogen that causes the respiratory disease -- if there are such similarities then we can conclude A The question asks the examinee to explain why the investigators conclude that the new pathogen is a hantavirus. Experiment 1 shows that the pathogen has antigens that are similar to those of a known hantavirus. Experiment 2 shows that the pathogen carries genes that are significantly similar in sequence to genes of two known hantaviruses. Taken together, these results support the conclusion that the pathogen is related to known hantaviruses (A). Because viruses other than hantaviruses can infect lung tissue and because known hantaviruses can infect tissue other than lung tissue, the observation that this pathogen infects lung tissue (B) does not demonstrate that the pathogen is a hantavirus. C is incorrect because the pathogen was infecting a different kind of tissue (lung) than the known hantavirus discussed in the passage was infecting (kidney). D is incorrect because the absence of pathogenic bacteria in infected tissue is not proof that the pathogen is necessarily a specific kind of virus. Thus, A is the best answer.
penetrance vs. expressivity
-penetrance: •the proportion of the population with a given genotype who actually express the phenotype •a population parameter -expressivity •the different manifestations of the same genotype across the population (ex. skin color... some people are darker and some people are lighter) •looks at the individual level complete penetrance --> all individuals have it at the same degree complete penetrance with variable expressivity --> all individuals have it but express the phenotype at varying levels incomplete penetrance ---> not all individuals have it but the ones that do have it to the same degree incomplete penetrance with variable expressivity --> only some individuals have it and the phenotype varies at different levels
An increase in pH from 7.0 to 8.0 means the water is _____ times more basic. An increase in pH from 7.0 to 9.0 means the water is _____ times more basic. An increase in pHfrom 7.0 to 10.0 means the water is ______ times more basic
1. 10 2. 100 3. 1,000 ** if the pH decreased then it would ___ times more acidic pH change is an increase or decrease in conc. of H+ to OH-
How does a western blot work?
1. do gel electrophoresis and allow proteins to travel in gel 2. add proteins to protein binding membrane 3. add something like low-fat milk or BSA to block regions of the membrane without any protein so that antibodies that are added only bind to the proteins and not anything else --> this is called blocking nonspecific antibody binding 4. incubate with antibodies --> use primary antibodies and we like to use secondary antibodies because it creates higher detection (darker line) because the more antibodies, the more labels 5. wash to remove antibodies that aren't binding 6. use fluorescence to detect antibodies
what would each scenario alter urin output? 1. increased osmotic pressure of the tubule 2. increased hydrostatic pressure of the tubule 3. increased osmotic pressure of the peritubular capillaries 4. increased hydrostatic pressure of renal artery 5. increased osmotic pressure of filtrate
1. it would increase urine output because tubules (PCTubule, DCTubule etc) would draw fluid into it which increases urine excretion 2. fluid from tubule would go into the capillarie so less urine output 3. more fluid comes into the capillaries so decreased urine output 4. more fluid is going to be flowing through the artery so increased urine output 5. filtrate is what is in the nephron so if filtrate is drawing in more fluid into the tubules then in would cause increased urine output
each pH change from the pka or any pH change in general causes the ratio of protonated to deprotonated to change by a factor of ______
10
every NADH that enters ETC pumps ____ protons into the inter membrane space every FADH2 that enters ETC pumps ____ protons into the inter membrane space need _____ protons to make 1 ATP
10 H+ per NADH 6 H+ per FADH2 4 H+ per 1 ATP
how much does each AA weigh?
110 Da or 0.110 kDa
Autosomal Recessive Inheritance vs Autosomal Dominant
2 parents who are unaffected have at least one child that is affected parents are HETEROZYGOUS Skips generations, usually seen in only 1 generation. 25% of offsprings from 2 carrier parents affected. Often due to enzyme deficiencies, more severe than dominant disorders; symptoms presents in childhood. females need 2 copies of the affected gene to cause the disease Dominant: 2 affected parents have a child that is not affected -- parents are HETEROZYGOUS
Describe the amide bond
2 resonance structures is what gives the partial double bond character RESTRICTED ROTATION at the double bond resonance stabilized PLANAR not tetrahedral
translation begins when ribosome bind to ____
5' cap on mRNA (euk) 7-methylguanosine methylated guanosine (nitrogenous base) shine delgardo sequence on prokaryotes
how many codons do we have total?
64 codons 61 codons that correspond to AA because 3 correspond to stop codons, which are not associated with an AA 20 AA
How many histones are in a nucleosome?
8 (2 of each type) = octomer core H2A, H2B, H3, H4 H1 is a linker histone which secures the DNA to histone
nucleotide mutation
A --> G just change of one base/nucleotide
If the e and f genes are expressed, the Xi chromosome will be prevented from reaching 100% frequency if selection pressures cause which of the following to be true? a. XsXs flies have the lowest fitness of any genotype. b. XsXs flies have the highest fitness of any genotype. c. XiY flies and XsY flies have equal fitness. d. XiXs flies and XsXs flies have equal fitness.
B makes sense because if it has the highest then it would make way more Xs than Xi The correct answer is B. The passage says that, if none of the Xi bearing genotypes is selected against, the frequency of Xi will increase to 100%. Since not being selected against is equivalent to having equal fitness, options C and D are incorrect. If fitness is not equal among all the genotypes and the XsXs genotype has the highest fitness, this would increase the proportion of Xs in relation to Xi in the population counteracting the drive to increase Xi at the expense of Xs, so option B is the correct answer.
Symptoms of burning, itching, and pain occur when DDT is absorbed through the skin because: motor neurons are depolarized motor neurons are hyperpolarized sensory neurons are depolarized sensory neurons are hyperpolarized
C sensations create APs -- so depol (also talks about Na+ so I knew it was depol) Sensory neurons are afferent neurons. Motor neurons are efferent neurons. Because DDT causes burning in pain when in contact with skin, it must be activating sensory neurons because the reaction with the skin is causing THE SENSATION of pain and burning. DDT > sensory neurons > CNS > interpretation of pain. If you put your hand on a hot stove the heat activates sensory neurons which integrate signals to the CNS which will send a signal to a motor (efferent) neuron to remove your hand from the stove. Any sensation ever is coming up to your brain through sensory neurons and is processed there, and there is not necessarily any output. For example, if I was laying g perfectly still and I had an itch on my leg, but resisted the urge to scratch it, only sensory neurons would be at work. They would be sending the info up to my brain saying 'hey, your leg is itchy' . There is no output coming down to my leg that puts the sensation there or anything. You feel it in your leg because your brain interprets that that is where it is coming from. If I decided to go ahead and scratch it, my efferent neurons would work to move my arm, but this would be pretty much the only output involved.
Plasma clearance is affected by the tubular transport maximum (Tm) of a substance. The Tm is the maximum rate of transport (mg/min) at which a substance can be reabsorbed by the kidney. That is, if the filtration rate of a substance exceeds its Tm, the substance will begin to appear in the urine. The Tm for glucose averages 320 mg/min in an adult human. According to the passage, the Tm represents the rate of plasma filtration that just exceeds the: A) rate of concentration of the substance in the glomerular filtrate B) rate of concentration of the substance in the urine C) capacity of the kidney tubules to reabsorb the substance D) capacity of the bladder to store and excrete the substance
C- misunderstanding question... the Q says... according to the passage, the T, represents the rate of plasma filtration that exceeds ____ so we need to figure out what exactly plasma filtration exceeds and the passage says "filtration rate of a substance exceeds its Tm"... so what is Tm? the passage states Tm is "the maximum rate of transport (mg/min) at which a substance can be reabsorbed by the kidney" so that is why C would make the most sense The correct answer is C. Suppose one gradually increased the rate at which fluid was expressed from the bloodstream (the glomerular filtrate rate) and measured the concentration of some substance reabsorbed by the kidney as it left the distal tubule as urine. The concentration might not rise at first, because the cells lining the tubule might be completely reabsorbing the substance and putting it back into the blood stream. Eventually, however, the rate of flow would reach a point at which it exceeds the rate at which the tubule cells could reabsorb the substance. The fluid would be flowing too rapidly through the tubule for the cells to reabsorb all the substance. The rate of flow through the tubule at which the substance begins to be observed in the urine is Tm. At that point the rate of flow of fluid through the tubule begins to exceed the capacity of the kidney tubule cells to reabsorb the substance. This description of Tm is given only in answer choice C, the correct answer.
A lower-than-normal blood pressure will cause which of the following effects on the rate of plasma clearance of Substance A? A) An increase, because the concentration of Substance A in the urine will increase B) An increase, because the ADH levels will be very low C) A decrease, because the decreased rate of urine output will allow more reabsorption by the kidney D) A decrease, because ADH levels will be very high
C- you should just know that what happens when BP is low? less filtrate would flow through the kidneys.. for this reason plasma clearance (aka the degree to which a substance is removed from blood plasma and excreted through urine) would decrease... this is because as the glomerular flow rate decreases, there is more time for reabsorption by the kidneys so most of the substance will all be reabsorbed back into the bloodstream rather than get excreted in urine ADH would be more beneficial to the reabsorption of water instead of affecting plasma clearance Low blood pressure could have an effect on ADH levels (as suggested in answer choices B and D), which could, in turn, affect the amount of substance A in the urine, but there is not enough information in the passage to decide if such an effect exists and, if it does, whether its effect would overcome the certain affect of lowering the blood pressure. The best answer is answer choice C: that low blood pressure decreases the glomerular filtration rate, allowing more time for reabsorption and decreasing the amount of substance A in the urine. Blood pressure is the source of the energy that forces fluid into the capsular space. If the heart stopped and the blood in the glomerular capillaries had no hydrostatic pressure, fluid in the space around the glomerulus would flow back into the capillary bloodstream. This would occur because the protein-rich blood would be hypertonic with respect to the protein-poor fluid in the capsular space so that the fluid would flow down the osmotic gradient into the blood.
chemoreceptors check the partial pressure of ____ in _______
CO2 in the blood
Cholecalciferol vs calcitiriol vs calcitonin
Cholecalciferol is VIT D (which is inactive) and it is activate by PDH to form calcitriol (increases phosphate and calcium reabsorption by the gut) calcitonin -- decreases blood calcium levels
What is articular cartilage?
Covers the external surface of the epiphyses Made of hyaline cartilage Decreases friction at joint surfaces - protects joints (how robert was saying an individual with osteoarthritis will have less cartilage between their bones which will decrease compression and increase friction between the bones)
If the anti-inflammatory drug in Treatment 1 interfered with DNA replication, in which phase of the cell cycle would cells tend to be arrested? A. G0 phase B. G1 phase C. S phase D. G2 phase
DNA replication occurs during the S or synthesis phase of a cell cycle. Thus the cell cycle would be arrested in this particular phase of the cycle and not in G0, G1, or G2 phases. Thus, answer choice C is the best answer.
Mitochondrial inheritance
Disease occurs in both males and females, inherited through females only if mom has it then ALL children have it
Postmenopausal women receiving estrogen and progesterone therapy will most likely experience which of the following side effects? A. breast tissue atrophy B. vaginal tissue will dry out C. periodic menstruation will resume D. lactation will be induced
Estrogen and progesterone are actively secreted by the ovaries of pre-menopausal women and act to maintain the uterine cycle. With advancing age the ovary becomes less responsive to pituitary gonadotropins and cyclical changes in the endometrium of the uterus disappear. -- so as LSH and FSH gets pushed out ovaries are less sensitive so it isn't going to be making estrogen and progesterone at normal levels so that's why the period stops so if we add these hormones then the body will start the period again The menstrual cycle can be re-established by administration of estrogen and progesterone in a regimen that approximates the rise and fall of hormone levels in pre-menopausal women. So the correct answer is answer choice C, periodic menstruation will resume. To the extent that the therapeutic dosages are typical of pre-menopausal women, side effects such as breast tissue atrophy (answer A), vaginal tissue drying (answer B) and lactation (answer D) would not be expected to occur.--
"An XsY male is standard: he sires equal numbers of sons and daughters. An XiY male expresses the sex ratio trait: he sires only daughters. Total reproductive output is not affected; XsY males and XiY males sire equal numbers of offspring. If none of the Xi-bearing genotypes (XiY, XiXi, or XiXs) is selected against, then the frequency of Xi is expected to increase to 100%, unless other genes act to suppress expression of e and f." If all genotypes are equally fit and if there are no genetic modifiers of the sex ratio trait, what will be the ultimate fate of a population in which 50% of the X chromosomes are currently Xi and 50% are Xs? A. Extinction B. Stable population size, with a predominance of females C. Stable population size, with all individuals producing a 50:50 sex ratio D. Stable population size, with some individuals producing an excess of females and some producing an excess of males
Extinction makes sense because more and more females will keep being made and less and less males will be made... then it will get to a point where no more males are made so the population would die out The correct answer is A. The passage states that if none of the Xi genotypes are selected against, then the Xi chromosome will increase to 100%. If all the males are XiY, then only females will be produced and the population will become extinct. Answer A is correct. The population will not be stable, but will increasingly become female, so options B and C are incorrect. Option D is also incorrect, not only because it assumes a stable population size, but also because it supposes that some individuals will produce an excess of males.
when codominance occurs what generation is it in?
F1 or the first generation
what directly stimulate sertoli cells?
FSH and testosterone (androgens) leydig cells contribute INDIRECTLY bc they make androgens
T or F: all lipids are hydrolyzable
False all lipids are able to be emulsified via micelles but not all of them are able to be hydrolyzed by lipases
"Although all individuals (male and female) steadily lose 0.5 to 1.0% of their bone mass per year after the age of 40, this decline is accelerated in postmenopausal women, who show a loss of 2 to 3% per year for the 8 to 10 years immediately following menopause. They then revert to the slower rate of loss. Aging-related abnormalities in parathyroid hormone and calcitonin secretion contribute to the slow decline of bone mass in both men and women, as does decreased production of active vitamin D by the kidney. The accelerated postmenopausal bone loss in women appears to be directly linked to estrogen deficiency, although the exact mechanism of this linkage is unknown." A man is treated with low doses of an estrogen analogue to destroy an estrogen-responsive adrenal tumor. Compared to an age-matched control (no estrogen treatment), this patient's chances of developing osteoporosis will most likely be:
From passage: -both men and women lose bone mass BUT it is accelerated in women following menopause... -PTH, calcitonin, and Vit D contribute to this for men AND women -it accelerates in women because of an estrogen deficiency Administration of estrogen to men would then have no therapeutic effect on bone loss, since they should not be suffering from withdrawal of the hormone, having never had high levels. Men given estrogen should have the same chance of developing osteoporosis as a control population -because they are only getting low doses, it shouldn't significantly impact them
"Vertebrates that have evolved in deserts are better adapted than humans for maintaining homeostasis in hot, dry environments. When severely dehydrated, humans can produce urine that is 4 times as concentrated as plasma. However, camels can more than double, and kangaroo rats can more than triple, the urine-concentrating capacity of humans. Reptiles, which lack sweat glands, maintain homeostasis by means of lower metabolic rates and scaly, relatively impermeable integuments." When the environmental temperature is 45° C, which of the following organisms will have the highest body temperature? A. human B. Kangaroo Rat C. Camel D. Lizard
GTK The correct answer is D. The question asks the examinee to identify the organism with the highest body temperature in response to elevated external temperatures. This organism will be the organism that is least able to utilize the cooling mechanisms of vasodilation and sweating. A lizard (D) has an impermeable integument, thereby eliminating vasodilation and sweating as options for cooling. Thus, D is the best answer.
Are Gram-positive or Gram-negative bacteria more sensitive to antibiotics?
Gram positive bacteria are more sensitive gram negative bacteria have an outer membrane which are able to be altered to make them harder to penetrate by doing things like changing the hydrophobic properties or mutations in porins -- making them build a resistance to antibiotics (porins are: Porins are primarily involved in passively transporting hydrophilic molecules of various sizes and charges across the membrane -- so if porins are mutated then less things are able to come into the cell) Gram neg bacteria also have lipopolysaccharides lining the outer membrane which are toxic and harmful to the host
How are helper T cells activated?
Helper T-cells bind to professional antigen presenting cells (APC) and the helper T-cells are activated they are the ones that differentiate into memory T cells (like memore B cells) and effector T cells (which activate B cells and releases cytokines) **when cytotoxic T cells are activated, they kill cells
what is the units for rate?
IT WILL ALWAYS BE CONCENTRATION/TIME
"The ciliate protozoan Tetrahymena contains two nuclei: a diploid, germ-line micronucleus and a 45-ploid macronucleus that is the site of gene expression during the vegetative state. Sexual reproduction in Tetrahymena occurs by the process of conjugation" When an initially heterozygous macronucleus undergoes repeated binary fission, the result will be: A. loss of macro nuclear chromosomes B. increased rate of crossing over in the macronucleus C. production of macronucleus with a genetic origin distinct from the micronucleus D. variable allele distribution in the macronucleus
In the passage it states that the macronucleus is 45-ploid. If haploid cells have one copy of each chromosome and diploid cells have two copies of each chromosome, then one can infer that 45-ploid cells have 45 copies of each chromosome. Polyploidy, having more than two copies of each chromosome, is unusual in animals, but important in plants and microorganisms like Tetrahymena. The amitotic division of the macronucleus will result in uneven distribution of chromosomes, hence an unpredictable genome. Answer D is therefore correct; the allele distribution will be uneven. Given the large numbers of identical chromosomes in the macronucleus, however, repeated divisions are unlikely to result in the loss of a chromosome, so choice A is incorrect. There is no crossing over in the production of a macronucleus, because the phenomenon of crossing over is a very complex and specialized event that occurs only when meiosis will be taking place, so B is incorrect. C is incorrect because all macronuclei trace their origin ultimately to their micronucleus.
transmembrane proteins
Integral proteins that span the membrane are hydrophobic (made up of NP AAs) interact favorably with hydrophobic tails of phospholipids in the cell membrane and unfavorably with hydrophilic
cell membrane vs plasma membrane
Is plasma membrane and cell membrane the same thing? No, plasma membrane and cell membrane are not the same. Plasma membrane is the membrane surrounding the organelles. On the contrary, cell membrane is the membrane that surrounds the entire cell.
In Experiment 2, the increased blood pressure resulting from the higher-than-normal concentration of ADH most likely affected the urinary output of Substance A by increasing the: a. glomerular filtration rate. b. Tm of solutes. c. water reabsorption from the tubules. d. concentrating ability of the loop of Henle.
LOL literally going over it, you said "glom filtration rate"... you know the stuff, don't let the answer choices throw you off you need to answer the question... it is asking why the urinary output of substance A will increase -- so if BP increases bc of increased ADH then the glomerular filtration rate will increase so urinary output will increase -- and when the glomerular filtrate rate increases, then more stuff will be excreted through the urine rather than be reabsorbed The correct answer is A. The best answer is that increased blood pressure will affect the glomerular filtration rate, answer choice A. Tm is a characteristic that depends on the characteristics of the cells lining the renal tubules and independent of blood pressure, so answer choice B is not correct. Water resorption and concentrating ability are the same, so answer choices C and D are essentially the same. Increasing blood pressure should increase flow of fluid through the kidney system and decrease, rather than increase, water reabsorption, so these answer choices are incorrect.
What is a Robertsonian translocation?
Long arms of 2 acrocentric chromosomes fuse, and short arms are lost
Why does low blood calcium create muscle spasms?
Low ionized calcium levels in the extracellular fluid increase the permeability of neuronal membranes to sodium ion, causing a progressive depolarization, which increases the possibility of action potentials. calcium normally inhibits sodium channels which stops depolarization but once Ca2+ levels are low, it no longer can inhibit Na+ channels
Monosomy vs. Trisomy
Monosomy- one missing 2n -1 = 45 n -1 = 22 **Monosomies are lethal... think of it as not having enough of a supply to form things Trisomy- one extra 2n + 1 = 47 n + 1 = 24 normal or euploid --> 2n = 46 and n = 23
Myoglobin
Myoglobin is the substance that holds oxygen in the muscles AND organs.
what are N-linked carbohydrate chains?
N (asparagine) - asparagine has carb residues added to them in the ER which tell the proteins to go to the correct location
where do you cleave when you want to cleave a phosphate off of an NTP?
NTP --> UTP, GTP, ATP, ETC cleave at the gamma phosphate, which would be at the end when adding things you add to the alpha phosphate then beta then gamma is the end (tri-3) if you want to cleave a pyrophosphate then you cleave at the beta phosphate to release PPi
what happens when NTPs are cleaved?
NTPs like ATP, GTP, UTP are always going to be EXERGONIC!!! They release energy when breaking bonds which powers other reactions endergonic to make covalent phosphodiester bond exergonic to break covalent bond and release PPi ***exception to BARF
X-linked recessive inheritance vs X-linked dominance
No male to male transmission (mutation is only on the X chromosome). Son of heterozygous mothers have a 1/2 chance of being affected. usually sons are getting it from the moms (daughters are usually carriers) if dad is affected then he creates daughters that are carriers and no sons affected if mom has it then 50% chance sons will have it and 50% chance daughter are carriers but with X-linked dominant --> mom has 50% chance of passing it onto her children.. only need one for females to have the disease while with X-linked recessive females need 2 males only need one for both so with X linked dominant if a dad has it then all females will have it
northern blot vs RT PCR?
Northern = only display qualitatively based on band patterns. RT-PCR/qPCR give you fold differences in relative gene expression.
what is nuclear division vs cytoplasmic division referring to?
Nuclear division divides the genetic material in the nucleus, while cytokinesis divides the cytoplasm. There are two kinds of nuclear division—mitosis and meiosis. Mitosis divides the nucleus so that both daughter cells are genetically identical.
Osmotic vs Oncotic Pressure
Osmotic Pressure = ""Sucking"" pressure that draws water into blood --> it is the movement of water -- can still refer to proteins but with oncotic we cannot talk about molarity due to solutes like salt leading to the movement of water Oncotic Pressure = Osmotic Pressure specifically caused by Proteins like albumin
PDH phosphorylase vs kinase
PDH phosphorylase activates PDHC -- stimulated by Mg2+ and Ca2+ PDH kinase inhibits PDHC -- stimulated by ATP, NADH, acetyl-coa inhibited by: ADP + Pi, NAD+, pyruvate, COASH, Ca2+
what is lipoid acid used for?
PDHC without it pyruvate cannot be made into acetyl CoA pyruvate ---> acetyl-cao is oxidative decarboxylation because we form CO2 and something is being reduced (NAD+) and something is being oxidized (lipoic acid)
Can bacteria do cellular respiration?
Prokaryotic cells carry out cellular respiration within the cytoplasm or on the inner surfaces of the cells. More emphasis here will be placed on eukaryotic cells where the mitochondria are the site of most of the reactions. bacteria do ETC but it occurs in the plasma membrane! -- they have the same things as us like ATP synthase
Which of the following correctly pairs a cellular process with the location in which that process occurs in a prokaryotic cell? A. transcription, cytoplasm B. ATP synthesis, mitochondria C. degradation of macromolecules, lysosomes D. modification of carbohydrates on transmembrane proteins, golgi complex
Prokaryotic cells do not contain nuclei, membrane-bound organelles in which nuclear genes are transcribed in eukaryotic cells. Consequently, transcription occurs in the cytoplasm of bacterial cells. Thus, A is the best answer. mitochondria, lysosomes, and the golgi complex are all membrane bound organelles so they would not be present in the prokaryotic cell -- because the prokaryote does not have a nucleus, it does transcription and translation simultaneously in the cytoplasm
Qualitative vs. Quantitative Data
Qualitative: recorded descriptions like what is being observed Quantitative: usually numbers (tables & graphs) statistics are usually used to analyze the data
how do disulfide bonds form and break?
REDOX form via oxidation release 2 H+ and 2 e- break via reduction add 2 H+ and 2 e-
Which AAs are more likely to get phosphorylated and why?
STY serine, threonine, and tyrosine this is because they have an -OH on there, which is likely to get phosphorylated
what AAs does the post-translational modification: phosphorylation involve?
STY (which are usually neutral until they get a phosphate added to them which creates a negative charge)
A male taking excess testosterone may become infertile because of reduced spermatogenesis. According to Figure 2, this could result directly from: (flip for image) A. an increase in inhibin concentration B. a reduction in inhibin concentration C. reduction in FSH concentration D. reduction in LH concentration
Sertoli cells are responsible for spermatogenesis. Knowing that and looking at figure 2, you have to determine which answer choice would be closest to affecting the Sertoli cells. -we see that testosterone inhibits hypothalamus and pituitary gland but the reduction of spermatognesis is due to directly to the reduction of FSH which would prevent sertoli cells to make more sperm so the person would become infertile Figure 2 indicates that testosterone is part of a negative feedback loop that acts on the hypothalamus to prevent the release of GnRF. In the presence of testosterone, less GnRF would be present to stimulate the release of FSH from the pituitary gland, causing a decrease in FSH available to act on the Sertoli cells. Therefore, FSH is less able to promote and maintain spermatogenesis. Thus, C is the best answer.
T or F: all monosaccharides are reducing sugars
TRUEEEE ALL MONOSACCHARIDES ARE ALL REDUCING SUGARS disaccharides have reducing sugars (lactose and maltose) and nonreducing sugars (sucrose)
telomeres contain repeats of:
TTAGGG ONLY and only telomerases (RNA dependent DNA polymerase-- makes DNA using RNA as template) can replicate telomeres NOT DNA POLYMERASES (which are used for DNA synthesis)
LD50 vs ID50
The ID50 is the infectious dose that will cause 50% of people exposed to a pathogen to become contaminated. estimated number of organisms or virus particles required to produce infection in 50% of normal adult humans exposed by a given route LD50 is the minimum lethal dose to kill 50% of the population when looking at LD50 or ID50 always pay attention to the 50% mark
Capillaries in the kidney and elsewhere in the body maintain fluid homeostasis by balancing hydrostatic and osmotic pressures. Which of the following is the initial effect of a blood clot forming on the venous side of a capillary bed? A. net fluid flow in the direction of interstitial spaces will increase B. net fluid flow in the direction of interstitial spaces will decrease C. capillary osmotic pressure will increase D. capillary osmotic pressure will decrease
The correct answer is A. After introducing the idea of fluid homeostasis, which is obtained by balancing hydrostatic and osmotic pressures, the question asks the examinee to predict the consequences of a blood clot on the venous side of a capillary bed. To answer this, it is necessary to know that blood flows from arteries to capillaries and then to veins. If flow is blocked at the venous side, blood would accumulate in the capillaries. Thus, hydrostatic pressure would build up in the capillaries, causing a net increase in fluid flow into the interstitial spaces. A is therefore correct. B is incorrect because there will be an increase in net fluid flow into the interstitial spaces, not a decrease. C is not the best answer because the increase in osmotic pressure in the capillaries would be an indirect result of the fluid flow out of the capillaries. D is incorrect because the flow of fluid out of the capillaries would slightly increase, not decrease, the osmotic pressure. Thus, A is the best answer. osmotic pressure increases because: Fluid gets forced out into the interstitial space, but the actual solid pieces of the blood do not. So you can picture the blood in the capillaries becoming more concentrated while the fluid in the interstitial space becomes more dilute. Higher osmolarity in the capillary means the fluid will try (but fail, because of the heart) to get back in, which increases the osmotic pressure.
Uric acid enters the urine both through filtration and secretion in the kidney. The process of filtration of uric acid in the kidney takes place in the: A. glomerulus B. loop of henle C. distal convoluted tubule D. proximal convoluted tubule
The correct answer is A. Filtrate is formed as fluid passes from the glomerular capillaries through the glomerular membrane into the Bowman's capsule. This region of the nephron is known as the glomerulus. Thus, A is the best answer.
The confining membrane shown in Figure 1 is most similar structurally to a: (flip for image) A. eukaryotic cell membrane B. prokaryotic cell membrane C. bacterial spore coat D. bacterial capsule
The correct answer is A. Many viruses form infective particles (virions) by budding off the surface of eukaryotic cells and becoming enclosed in a vesicle composed of the host's cell membrane. Such eukaryotic cell membrane is made up of a bilayer of amphipathic lipids with associated proteins. The diagram shows such a membrane, so the answer must be A. Most bacterial cells (prokaryotes) have an additional, thicker carbohydrate wall. Cell walls (choice B), spore coats (choice C) and capsules (choice D) do not have the lipid bilayer structure shown.
Drugs affecting the ANS may have either an "active" mechanism (that mimics the activity of the PS or the S division) or a "passive" mechanism (that blocks the effect of the opposing division). The drug atropine prevents acetylcholine from attaching to its receptors on the circular muscle. Is this mechanism active or passive? A. passive because PS innervation is blocked B. passive because S innervation is blocked C. active because PS innervation is mimicked D. active because S innervation is mimicked
The correct answer is A. The blockage of acetylcholine receptors by atropine is a passive mechanism as defined in the question. Atropine prevents acetylcholine from exerting its effect by preventing its binding to the acetylcholine receptor. An example of an active mechanism would be the administration of an acetylcholine-like drug which would mimic the effect of acetylcholine. Thus, answer choice A is the best answer.
Most proteins in present-day mitochondria are made by cytoplasmic ribosomes from mRNA transcribed from nuclear genes. Can this fact be reconciled with the hypothesis described in the passage? A.Yes; the transfer of genes from symbionts to the eukaryotic nucleus could have occurred during the last billion years of evolution. B. Yes; this difference from bacteria is unimportant, because the many similarities between bacteria and mitochondria provide sufficient evidence in favor of the hypothesis. C. No; the fact that mitochondrial proteins are made in the cytoplasm is convincing evidence that mitochondria do not have a bacterial origin. D. No; because bacteria can make all their own proteins and mitochondria cannot, this disproves the hypothesis.
The correct answer is A. The endosymbiotic theory described in the passage is widely accepted today, so there must be some way of using the theory to reconcile the fact that mitochondrial proteins are made in the cytoplasm. We know, for example, that lateral transfer of genes from one genome to another is widespread among living organisms. It would have been an easy matter for mitochondrial genes to be acquired by the host cell nucleus and to disappear from the mitochondrial genome. It is likely that this exchange would have resulted in a net gain in efficiency for the composite organism. Answer choice A is therefore the most plausible answer. Despite many similarities between mitochondria and bacteria, the question of cytoplasmic synthesis of mitochondrial proteins is relevant to the question of the origin of mitochondria and needs to be answered. The fact that mitochondria do have all the machinery (ribosomes, t-RNA, etc.) for protein synthesis eliminates answer choice C from consideration.
A stable, differentiated cell that will NOT divide again during its lifetime would most likely be found in which of the following stages of the cell cycle? A. G1 B. G2 C. M D. S
The correct answer is A. The question asks the examinee to identify the cell cycle stage in which a stable, differentiated, nondividing cell will most likely be found. A diploid, nondividing cell is most likely in G0 or G1, in which the cell remains metabolically active but is not replicating its DNA (S) or segregating its duplicated chromosomes and dividing (M). A is the only option that lists either G0 or G1. Thus, A is the best answer.
In human females, mitotic divisions of oogonia that lead to formation of presumptive egg cells (primary oocytes) occur between: A. fertilization and birth only B. fertilization and puberty only C. birth and puberty only D. puberty and menopause only
The correct answer is A. The question asks the examinee to identify the stages in the human female life cycle between which all the mitotic divisions that lead to primary oocytes occur. These stages occur in the following order: fertilization, birth, puberty, menopause. All of the mitotic divisions that form primary oocytes occur prior to birth. Thus, A is the best answer. after birth, eggs go from prophase I to metaphase II once a month from primary to secondary oocytes
Assuming that the vertebrates were all of comparable size, which of the following vertebrates would be expected to have the strongest and heaviest bones? A. a land-dwelling mammal B. water dwelling mammal C. flying bird D. amphibian
The correct answer is A. The question asks the examinee to identify which vertebrate is likely to have the strongest and heaviest bones. Of the animals listed, a land-dwelling animal would be expected to have the heaviest bones (A), since enhanced bone density would be required to withstand the load bearing activity that results from the impact of gravity on land-dwelling animals. Less dense bones would be present in water-dwelling creatures (B) and amphibians (D), since the impact of gravity would be ameliorated by life in an aquatic environment. Likewise less dense bones would be a necessity for flight (C). Thus, A is the best answer.
The osmotic concentration of plasma proteins in the venous side of capillaries helps reduce the amount of interstitial fluid in tissues by inducing: A. passive H2O diffusion along a concentration gradient B. passive ion diffusion along an electrochemical gradient C. facilitated ion transport along an electrochemical gradient D. active H2O transport mediated by an ATP-dependent pump
The correct answer is A. The question asks the examinee to identify why the osmotic concentration of plasma proteins on the venous side of capillaries helps reduce the amount of interstitial fluid. A is correct because it is the passive movement of water into the bloodstream that will most directly reduce the amount of interstitial fluid. B and C are incorrect because the effect of the plasma proteins is not to induce either passive or facilitated ion transport. D is incorrect because the water would not move by active transport. Thus, A is the best answer.
Hemophilia, a disease in which the time required for blood to clot is greatly prolonged, is determined by a sex-linked gene. Suppose a man with normal blood clotting marries a woman with normal blood clotting whose father was a hemophiliac. If this couple has three sons, what is the probability that hemophilia will be transmitted to all three of them? A. 1/8 B. 1/4 C. 3/8 D. 1/2
The correct answer is A. The woman inherited one X chromosome from her father and one from her mother. The father only had one X chromosome to contribute and that X chromosome contained the hemophilia gene. The mother will pass on one X chromosome to her sons, either the X chromosome containing the normal (wild type) gene, or the X chromosome containing the hemophilia gene. The probability of a son receiving the hemophilia gene and being a hemophiliac is 1/2, because there is a 50-50 chance that this son received an X chromosome carrying the defective gene from his carrier mother. The cumulative probability of all three sons inheriting the hemophilia gene would be the product of the individual probabilities, or 1/2 × 1/2 × 1/2. Thus, answer choice A, 1/8, is the answer.
Sarah noted that her skin blood vessels were usually constricted to conserve body heat in the cold environment of the mountains. However, her skin blood vessels would occasionally dilate for short periods of time. What would be the most probable physiological purpose for this periodic vasodilation? A. Maintain normal skin tone B. Maintain sufficient oxygenation of cells C. Reduce excessive blood pressure D. Maintain normal muscle tone
The correct answer is B. According to the item, Sarah noticed that her skin blood vessels were usually constricted to conserve body heat in the cold environment of the Colorado mountains where she went skiing. Occasionally, however, her vessels would dilate for short periods of time to enable a sufficient supply of blood (and oxygen) to her cells. Due to the physical exertion of skiing, her cells had an increased need for oxygen. Bc during exercises our muscles use up oxygen so we need to make sure that enough oxygen ends up to the muscles even during the cold
In a laboratory population of Drosophila, all the males are XsY. Among the females, 15% are XiXi, 50% are XiXs, and 35% are XsXs. Assuming random mating, what proportion of male flies in the next generation will be XiY?
The correct answer is C. All the males in the next generation will acquire a Y chromosome from their male parent, so the contribution of the male can be ignored in solving this problem. All the XiXi females will have XiY sons, so 15% of the XiY flies in the next generation will come from this type of female. Half of the sons the XiXs females produce will be XiY. Since XiXs females make up 50% of the population, 25% of the males in the next generation will come from this type of female. None of the sons of XsXs females will be XiY. The total number of male flies that are XiY is 40%; therefore, answer choice C is correct.
"Many structural and functional similarities between mitochondria and present-day bacteria support this hypothesis. They are approximately the same size, reproduce by similar means, and contain non-histone-bound DNA. They contain the tRNAs, ribosomes, etc., necessary for transcription and translation, and they show some similarities in base sequences of rRNAs." To support the symbiotic hypothesis presented in the passage, mitochondria should be similar to bacteria in which of the following ways? A. They should use 80S ribosomes. B. They should be incapable of binary fission. C. They should have circular DNA. D. They should be capable of anaerobic respiration.
The correct answer is C. Answer choice C is the correct answer because it states that the fact that mitochondria and bacteria both have circular DNA is a reason to think they are related. Such a characteristic is likely to have been highly conserved over time since it involves the basic material of life. Changes in the topology of the DNA molecule would involve substantial changes in the way the molecule replicated and the way it was transcribed. The fact that both have circular DNA supports the symbiotic hypothesis presented in the passage. Alternative choices A and B presented are not actually true characteristics of bacteria. Bacteria do have 70S ribosomes, not the 80S ribosomes of eukaryotes as stated in answer choice A and they do reproduce by binary fission, which choice B denies. The loss of ability to carry out anaerobic respiration (answer D) might be a product of the long history of association with the host cell. It is not unusual for symbiotic organisms to lose abilities that are compensated for by host functions.-- we also know mitochondria does ETC and Krebs which is aeorbic
Which of the following hormones is(are) directly required for spermatogenesis? I. Luteinizing hormone (LH) II. Follicle-stimulating hormone (FSH) III. Inhibin IV. Testosterone
The correct answer is C. Sertoli cells support and nourish the spermatocytes and promote the process of spermatogenesis. Spermatogenesis would not occur without Sertoli cells. The two hormones that directly stimulate Sertoli cells are FSH and testosterone (produced by the cells of Leydig). Thus, C is the best answer.
The autonomic nerve fibers that directly innervate the heart to cause cardiac slowing are: A. sympathetic motor fibers B. sympathetic sensory fibers C. parasympathetic motor fibers D. parasympathetic sensory fibers
The correct answer is C. The autonomic nerve fibers that innervate the heart to slow it are the parasympathetic motor fibers of the vagus nerve. Sympathetic motor fibers increase heart rate. Sensory fibers carry information from the heart to the central nervous system. Thus, answer choice C is the best answer.
"Alpha-adrenergic responses occur in tissues in which alpha receptors predominate. Typical alpha-adrenergic responses include widening of the pupils and constriction of blood vessels supplying the skin and mucous membranes." The amount of NE released by sympathetic nerve terminals will be most strongly influenced by a change in which of the following? A. alpha receptor sensitivity B. alpha receptor density C. Extracellular [Ca2+] D. COMT activity
The correct answer is C. The question asks the examinee to identify the factor among the options listed that will most strongly influence the amount of NE released by the sympathetic nerve terminal. Of these options, only C, extracellular [Ca+], will influence the amount of NE released by the sympathetic nerve terminal. When an action potential reaches a nerve terminal it triggers the opening of Ca+ channels in the neuronal membrane. Because the extracellular concentration of Ca+ is greater than the intracellular Ca+ concentration, Ca+ flows into the nerve terminal. This triggers a series of events that cause the vesicles containing NE to fuse with the plasma membrane and release NE into the synapse. Thus, C is the best answer.
Which organ is involved in regulation of all of the following: acid-base balance, blood pressure, water balance, and removal of nitrogen wastes? A. liver B. spleen C. kidney D. large intestine
The correct answer is C. The question asks the examinee to identify the organ involved in the regulation of acid-base balance, blood pressure, water balance, and the removal of nitrogenous wastes. The only organ involved in all of these processes is the kidney (C). Within the nephron, the reabsorption of protons and bicarbonate from the filtrate contributes to acid-base balance within the body; secretion of renin from the juxtaglomerular cells helps regulate the secretion of aldosterone from the adrenal cortex (which plays a role in regulating blood pressure, through its effects on Na+ reabsorption in the nephron); Na+ and urea reabsorption in the nephron creates osmotic pressure within the medullary interstitium of the kidney and draws water from the filtrate into surrounding tissues; and excretion of nitrogenous wastes takes place due to the urea transporter, which removes urea from the interstitium and transports it back into the ascending loop of Henle. Thus, C is the best answer.
An organism that causes a human disease is isolated and studied. Researchers conclude that the organism is a bacterium rather than a virus because the organism: A. undergoes mutation B. lacks a nuclear membrane C. contains protein in its outermost covering D. reproduces in a culture medium lacking host tissue
The correct answer is D. An organism that causes human disease is isolated and studies. Researchers would conclude that the organism is a bacterium rather than a virus if the organism reproduces in a culture medium lacking host tissue. Bacteria do not require host tissue to reproduce, whereas viruses do.
If the genetic and autoimmune theories of inflammatory bowel disease are true, then the gastrointestinal antigen being targeted by the immune system is probably on: A. the chromosomes carrying the genes for the disease B. part of the DNA segments constitution the genes for the disease C. stretches of the mRNA's coded for by the genes of the disease D. the surface of the proteins encoded by the genes for the disease
The correct answer is D. Assuming the genetic and autoimmune theories of inflammatory bowel disease are true, then the gastrointestinal antigen being targeted must be located on the surface of proteins encoded by the genes for the disease. Antigens are carried on the surface of cells, not on the chromosomes, DNA segments, or RNA. -antigens are on the surface of cells -- that is how immunoglobulins know to go and binds to them they are not inside the cells or on RNA, DNA, or chromosomes because then the immune system's antibodies would not be able to go and target the antigens
Production of which of the following hormones will be inhibited by the administration of dietary calcium to prevent osteoporosis? A. growth hormone B. calcitonin C. thyroid hormone D. parathyroid hormone
The correct answer is D. Calcium levels in the blood need to be kept constant. Parathyroid hormone and calcitonin regulate blood levels of calcium. The passage gave the information that calcitonin analogs inhibit osteoporosis. If calcitonin inhibits osteoporosis, it must function to take calcium out of the blood and into the bone while preventing the loss of calcium from bone into the blood. High levels of blood calcium available for deposit into bone should stimulate this process rather than inhibit it. Thus answer choice B, calcitonin, must be incorrect. Because growth hormone (answer A) and thyroid hormone (answer C) are not involved in the regulation of blood calcium levels, they are also incorrect. The correct answer must be parathyroid hormone (answer D) which is inhibited by high levels of calcium. A mnemonic students use to remember which hormone puts calcium into bone and which gets rid of it is: Calcitonin-in, parathroid-rid.
A hiker becomes lost and has no drinking water for 2 days. At the end of this time, which of the following changes in hormone production would be expected to be significant in this individual? A. decreased glucocorticoid secretion B. decreased aldosterone secretion C. increased insulin secretion D. increased antidiuretic hormone secretion
The correct answer is D. Glucocorticoid secretion by the adrenal medulla increases with stress, so it is unlikely that it would decrease in someone who was under the emotional and physical stress that situation suggests, so option A is incorrect. The need to conserve water in the body would lead to an increase in aldosterone secretion that would promote the retention of sodium ions. The retention of sodium ions would in turn promote the osmotic reabsorption of water by the kidneys so option B is incorrect. Insulin is responsive to levels of glucose in the blood. No information is given about the hiker's food supply, but it is reasonable to assume that insulin levels would not be increasing due to increased glucose levels in the blood so option C is incorrect. Antidiuretic hormone (ADH or vasopressin) secretion would increase to enhance the permeability of the distal tubules and collecting ducts of the kidney to promote water reabsorption and excretion of more concentrated urine. Therefore, response D is the best answer.
DNA polymerase catalyzes the replication of chromosomal DNA in bacteria as shown below. A double-stranded DNA molecule contains bases with a ratio of (A + T)/(G + C) = 3:1. This molecule is replicated with DNA polymerase in the presence of the four deoxynucleoside triphosphates with a molar ratio of (A + T)/(G + C) = 1:1. What is the expected ratio of (A + T)/(G + C) in the double-stranded daughter DNA molecule? A. 1:3 B. 1:1 C. 2:1 D. 3:1
The correct answer is D. The double stranded daughter DNA molecule would be an exact duplicate of the parent molecule. It would have the same (A + T)/(G + C) ratio. The correct answer is therefore 3:1, choice D.
In eukaryotes, oxidative phosphorylation occurs in the mitochondrion. The analogous structure used by bacteria to carry out oxidative phosphorylation is the: A. cell wall B. ribsosome C. nuclear membrane D. plasma membrane
The correct answer is D. The inner membrane of a mitochondrion is analogous to the plasma membrane of a prokaryote. The enzymes for oxidative phosphorylation are embedded in the inner membrane. The endosymbiotic theory suggests that mitochondria are descendents of prokaryotes that were engulfed by endocytosis into a vesicle lined with a membrane derived from the cell membrane of the eukaryote host. This is the outer membrane. The inner membrane is the plasma membrane of the endosymbiotic prokaryote, so answer choice D is correct. Answer choice A is incorrect because the cell wall of bacteria does not resemble a plasma membrane. Ribosomes have nothing to do with oxidative phosphorylation, so answer choice B is incorrect. Bacteria lack a nuclear membrane, thus answer choice C is also incorrect.
If acetylcholine is removed from the circulation faster than norepinephrine is, which of the following autonomic processes would be most rapidly inactivated? A. dilation of the pupils B. dilation of blood vessels in the skeletal muscles C. rise in blood pressure D. stimulation of digestive secretion
The correct answer is D. This question requires some prior knowledge of the function of the autonomic nervous system. The sympathetic division of the autonomic nervous system arouses the animal for "fight or flight." Blood is directed away from the digestive system and toward the skin and muscles; the digestive system becomes less active; the heart beats faster and with greater force; the bronchi of the lungs relax to let in more air; and the pupils of the eyes dilate. Rapid removal of acetylcholine from the circulation would inactivate parasympathetic stimulation of digestive secretion consonant with rapid arousal of the animal in an emergency. Thus, answer choice D is the best answer.
Which of the following media would most likely be used to grow virions in the laboratory? A. suspension of ribosomes and ATP B. suspension of human DNA C. nutrient broth D. tissue culture
The correct answer is D. Viruses take advantage of the elaborate intracellular mechanisms of the host cell using them to make more virus particles. To do this they need intact host cells. Non-cellular media such as the nutrient broths and suspensions in choices A, B and C will not support culture of viruses. They can be grown in tissue culture, so choice D is the correct answer. VIRUSES NEED CELLS TO GROW!!
Most viral proteins are produced directly by: A. translation of host nucleic acid B. translation of viral nucleic acid C. transcription of host nucleic acid D. translation of viral nucleic acid
Transcription is copying; translation is changing the language. In cellular metabolism transcription refers to taking DNA and making an RNA copy; translation refers to taking the RNA, a series of nucleotides, and putting it into protein language, a series of amino acids. Some viruses have a genome consisting of RNA and this can be directly translated by the ribosome. Others use DNA as the genetic material and require transcription as well. Both, however, ultimately make proteins by translating their specific RNAs into protein, so the answer is B. ***viruses typically use their nucleic acids (RNA -- sometimes DNA which would require transription) and use ribosomes from the host to make proteins via translation
What is ubiquitination?
Ubiquitination is the process of marking a protein for degradation allows proteosomes to recognize and degrade proteins via proteolysis (peptide pond cleavage) degrades damaged or unnecessary proteins/enzymes
What is adaptive radiation?
When a single species or small group of species evolve into multiple species happens when species are places in different environments because of natural selection
When someone gets severely burned, how can they no longer feel pain by touch?
because the dermis and epidermis contain receptors (mechanoreceptors) so when someone is burned severely, their receptors are destroyed so they no longer feel pain
Why would a burn victim have trouble with fluid loss?
because the epidermis (top layer of the skin) is destroyed and it has tight junctions and lipids that trap water in but when someone is burned, the lipids and tight junctions of the epidermis are destroyed which leads to fluid loss
how can prokaryotes do krebs and ETC anaerobically?
because the final electron acceptor for prokaryotes are inorganic ions instead of oxygen like in eukaryotes
What happens to self reactive T cells and B cells?
because they are self reactive, they are harming our own cells so they are killed via apoptosis B cells- killed in bone marrow T cells- killed in thymus ex. there are colon cells with self-antigens (or proteins on the surface-- MHC I receptors which mark these cells as ' self') that are body typically says "hey that's me" but when self-reaction occurs, the Bcells are like that's foreign so they (plasma cells) start making antibodies against the antigens that go bind so then T cells go and attack the colon in response to the antibodies from the B cells binding.... every nucleated cell in the body has MHC 1 receptors... makes sense because this is what tells cells that it isn't foreign normally when anything like this occurs other cells like Regulatory/Suppression CD4+ T cells come in and stop this
why is the difference in charge important for ETC?
because usually there are more protons in the inter membrane space than the mitochondria bc you have 3 of the complexes pumping H+ across to the inter membrane space and there is less H+ in the mitochondrial space the difference in charge (more positive charge in intermembrane space) or the difference in H+ ion concentration is the driving force (aka proton motive force) that is important for making ATP and pushing H+ against concentration gradient and into the mitochondrial space **if the pH on both sides is the same then no ATP will be made
Why do mammals on land have a heavier bone mass in comparison to water animals?
because water animals dont have to support their body against gravity
what kind of buffer solution if used in PCR?
because we add template with dNTPs (deoxyribonucleotide triphosphates), we are adding phosphates which have a negative charge --> high energy due to repulsion in order to stabilize this, if we add a buffer that is full of cations, then it can bind to the negatively charged dNTPs and stabilize the DNA so that when Taq polymerase and the primer binds, it is a thermostable environment primers have high G-C content bc working with high temperatures so you want strong bonds
BARF acronym
break (a bond) - absorb (energy) --> endergonic release (energy) - form (a bond) --> exergonic
What is anabolism in the body-- what does it make?
build up uses AAs, sugars, FA, nitrogenous bases to make macromolecules: proteins, lipids, nucleic acids, polysaccharides PRODUCES: ADP + Pi, NAD+, NADP+, FAD makes sense because it takes energy to reform macromolecules
what about fatty acids can increase fluidity?
by increasing the number of double bonds and decreasing the length of the FA chain (less hydrophobic interactions can occur)
how can we mimic phosphorylation of proteins (post-translational modification)?
by substitution AAs for aspartate (D) and glutamate (E) which have negative charges phosphorylation adds a negative charge so D & E are able to mimic this effect
To be an effective therapy, an antisense gene (complimentary to the sense mRNA are created to bind to mRNA and stop production of gene) that is incorporated into a genome that contains the target gene must be a. on the same chromosome as the target gene but not necessarily be physically adjacent b. on the same chromosome as the target gene and must be physically adjacent c. regulated in a similar manner as the target gene d. coded on the same strand of DNA as the target gene
c why? to provide effective therapy, this would need to be regulated in a manner similar to the manner in which the target gene is regulated so that the antisense RNA is produced at the same time that the sense mRNA is produced. This would ensure that the antisense RNA is available to bind with the sense mRNA not a b or d? the key feature determining whether and antisense drug will work is the timing of the expression of the antisense gene, which is controlled by specific regulatory elements, not the location. **Antisense drugs hybridize with and inactivate mRNA. This stops a particular gene from producing the protein for which it holds the recipe.
When does aneuploidy occur?
can arise in mitosis, meiosis (I + II) mitosis- aren't passed down from parent to child but can still cause cancer meiosis I --> when homologous chromosomes fail to separate correctly meiosis II --> when sister chromatids fail to separate correctly
what can fix protein aggregation?
chaperones (chaperone proteins) can correct the misfolding which can increase protein solubility
What is the integumentary system?
consists of skin, mucous membranes, hair & nails. This system also serves as a barrier to pathogens & helps regulate body temperture. integument = skin
another word for Dehydroxylation is ____
dehydration (either way OH is turning into H)
3 rule with frameshift mutation
deleting and inserting a number of nucleotides that is NOT divisible by 3 so 3, 6, 9, 12, etc would not cause frameshift
what happens if there is an issue with the detrusor muscle?
detrusor muscle is the smooth muscle of the bladder that contracts to allow pee to be released from the body... issues would cause urine retention (more urine stays in)
What is a viruses envelope made of?
envelopes are typically derived from portions of the host cell membranes (phospholipids and proteins), but include some viral glycoproteins. They may help viruses avoid the host immune system. Glycoproteins on the surface of the envelope serve to identify and bind to receptor sites on the host's membrane.
Which of the following experiments would best test the hypothesis that urease is necessary for the colonization of the stomach by H. pylori? A. Exposing ulcer to antibodies to urease B. Exposing uninfected animals to a strain of H. pylori that lacks urease C. Exposing ulcer patients to a radioactive urea D. Measuring urease activity in biopsies of ulcers
enzymes are located in cells and antibodies circulate in the bloodstream and bind to the outside to the cell For example, the enzymes that catalyze synthesis of fatty acids (a type of lipid ) are located in the cytoplasm , while the enzymes that breakdown fatty acids are located in the mitochondria .
what are nonspecific enzymes?
enzymes that are able to target different substrates at an equal affinity
other than genetic material what do viruses contain?
enzymes, lipids, proteins NO ORGANELLES OR RIBOSOMES viruses- tiny, nonliving cells so NO CELLS
Anomers are simply a special type of ______ and Epimers are simply a special type of _________.
epimers diastereomers anomers shows the alpha and beta forms of sugars
eukaryote vs prokaryote ribosomes
eukaryote- 80S --> large: 60S small: 40S pro- 70 S --> large: 50S small: 30S
arrange in order from biggest to smallest: bacteria virus eukaryotic cell
eukaryotic cell> bacteria> virus bacteriophages are viruses that track bacteria so they are smaller than bacteria human red blood corpuscle = eukaryotic cells so it is bigger than a virus
Euploid vs. Aneuploid
euploid = normal # of dna in the cell aneuploid = abnormal # of dna in cell -- one chromosome more or less in the cell
Which of the following changes in flow rate or in solute concentrations would NOT occur if the blood inflow rate were increased, increasing the pressure in the dialysis chamber? (flip for image) A. blood volume reaching the outflow tube per unit time would increase B. osmotic concentration of proteins in dialysate fluid would increase C. osmotic concentration of proteins in blood outflow would increase or remain unchanged D. the filtration rate across the dialysis membrane would increase
even if more blood came in bc of increased inflow, the proteins wouldn't go through dialysis membrane and into the dialysate fluid because proteins are too large to flow in and out of membranes like that (in passage it states "Protein molecules are too large to diffuse through the membrane") The correct answer is B. The question asks the examinee to identify which changes in flow rate or solute concentrations would NOT occur if the blood inflow rate were increased, consequently increasing the pressure in the dialysis chamber. The illustrations in the passage help clarify the location of the blood inflow, which comes from the patient and enters the dialysis machine. A, C, and D are incorrect because they identify changes that would occur. Blood volume reaching the outflow tube would increase per unit time (A). Osmotic concentrations of proteins in the blood would increase or remain the same because proteins are generally too large to pass through the membrane (C). The filtration rate across the membrane would increase because the pressure in the chamber would be greater (D). However, the osmotic concentration of proteins would not be expected to increase in the dialysate fluid because proteins generally do not pass through the membrane. Thus, B is the best answer
What is respiration?
exchanging oxygen and carbon dioxide with the environment breathing
what causes cells to differentiate?
expression of some genes with suppression of other genes cells use transcription factors and induction (external stimuli) --> get the cells around them to turn on and off -- get genes to differentiate into specific cell types **asymmetric distribution of products (mRNA and TFs-- some cells get more than others)
glycogenesis vs glycogenolysis
glycogenesis: stimulated by insulin --> adds glucose to glycogen glycogenolysis: stimulated by glucagon and epinephrine epinephrine works with GPCR and cAMP ... AMP stimulates pKA to activate glycogen phosphorylase which is the 1st step of glycogenolysis
where does glycosides occur vs gluconeogenesis?
glycolysis- CYTOPLASM only gluconeogensis- both the cytoplasm and mitochondria!! pyruvate is made into OAA via pyruvate carboxylase in the mitochondria... then it is either sent to the cytoplasm to turn into PEP via PEPCK or it uses mitochondrial PEPCK to turn into PEP
Because the hypodermis is a big layer of fat and fibrous tissue... we can label it as an
insulator
For each of the following write if insulin release and glucagon release increases or decreases: 1. glycogen synthesis 2. lipogenesis 3. protein synthesis 4. glycogenolysis 5. gluconeogenesis 6. lipolysis 7. ketogenesis
insulin release, glucagon release 1. inc, dec 2. inc, dec 3. inc, dec 4. dec, inc 5. dec, inc 6. dec, inc 7. dec, inc
Where do endocrine glands secrete?
into the blood stream so BLOOD NOT LYMPH VESSELS
why are spontaneous reactions irreversible?
irreversible because it took so much energy to make the reaction occur so it wouldn't want to proceed in the opposite direction **only happens in one direction
what AAs cause more steric strain?
large AAs cause more steric strain like FWY, LIM, KR
what AA is known to cause insulin secretion?
leucine which can decrease blood glucose levels
Linked genes vs Unlinked genes
linked genes- closer together on chromosomes --> makes nonrecombinant dna -- no combination occurs so original allele pairs remain so more offspring will be born with the same alleles as their parents (non recombinant offspring) unlinked genes makes recombinant dna --> which is more uncommon -- only about 2% chance -- allele pairs are affected -- combining of 2 or more dna
how can decreased liver function affect blood clots?
liver makes the coagulation factors, which promote blood clot formation so decreased liver function = decreased blood clots
How do you determine what the longest reading chain is of DNA?
look at the start codon (AUG) and the stop codon (UAA, UGA, UAG)
what is a quick trick to solve problems with AA?
look to see if there is a positive or negative charge is it gives you a positive charge then the answer may be the negative charge -- because it would increase interactions while like charges lead to repulsion **not always the case but could help
what happens when epithelial cells of the intestine are secreting lots of Cl- into the intestine?
lots of water from the blood would travel from the capillaries to the lumen of the intestine because wherever ions go water follows which would cause the individual to have loose stools (due to increased water excretion)
______ Km and ____ affinity creates a strong ES complex
low Km and high binding affinity would create a strong ES complex because the E and S want to associate with one another and that is why it doesn't take a lot of substrate to make it happen
what causes PTH to be released?
low blood Ca2+ Bone: which increases osteoclast activity (inc Ca2+ and PO43- release) Kidney: increases Calcitriol (Cholecalciferol is activated by PTH into Calcitriol) which inc Ca2+ and PO43- absorption by the gut increases kidney REABSORPTION of Ca2+ and EXCRETION PO43- (opp of gut)
histones are positively charged with the AA groups ____
lysine or arginine
tissue culture
make tissues or cells tissues are made up of cells and viruses use the cells to make viral proteins and make more viruses
what does insulin do for glut receptors?
makes more glut 4 receptors to go and bind to the cell membrane to let more glucose into the cell this can cause hypertension to decrease bc now there is less stuff in the blood vessels so less pressure
How does NADH get into the mitochondria?
malate-aspartate shuttle or uses the G3P shuttle, which oxidizes G3P into DHAP by converting cytosolic NADH into mitochondrial FADH2 and gives H+ to cyt c which goes to complex 2
how can phospholipids be separated by?
mass, charge, and solubility charged head groups = more soluble lipids with long hydrophobic chains = decreased solubility
why can't phagocytosis occur without MTs?
microtubules are essential for the shape of the cell (as well as microfilaments (actin) and intermediate filaments) in order for phagocytosis to occur, the cell needs to change shape and it is unable to do so if MTs aren't functioning MTs do polymerization and depolymerization in order to do this
What are prions?
misfolded versions of normal protein that can cause disease-- prions are misfolded proteins that are infectious and cause proteins to fold from alpha helix to beta sheet
what has to happen to proteins so that they fold properly?
most proteins need to undergo post-translational modifications like: glycosylation, prenylation, methylation, carboxylation, acetylation, ubiquitination, etc
What parts of the body is lined with mucous?
mouth, nose, eyelids, trachea (windpipe) and lungs, stomach and intestines, and the ureters, urethra, and urinary bladder
What is mutagenesis?
mutations arise-- so DNA alters ALTERS AA sequence
How do populations evolve?
natural selection Although many different types of adaptations may help an individual organism survive, they will not be passed on to the next generation unless the organism produces offspring, passing on the genes that cause the advantageous phenotype. To evolve by natural selection and become a general characteristic of the species, the genes must become a significant portion of the gene pool, which will most likely occur if individuals of the species with the trait produce more offspring than do individuals without them. this is due to theory of evolution by natural selection: overpopulation --> variation --> selection --> adaptation (inheritance)
Describe signal sequence
newly synthesized proteins have a signal peptide at the N-terminus that starts with the N that is positively charged followed by 16-30 amino acids (mainly hydrophobic) an SRP (signal recognition particle) recognizes the signal peptide and binds to it, which allows the ribosome to leave the cytosol and go to the rough ER to finish translation there -- SRP binds to a receptor on the lumen and signal peptide gets cut -- protein is secreted into the lumen
do small FA use the carnitine shuttle?
no because they can just diffuse through the membrane of the mitochondria while large FA must: 1. activation: fatty acid acyl-coa synthetase activates FA using acetyl coA and ATP --> AMP + PPi & Acyl-coA 2. carnitine acyltransferase (rate limiting step of B-oxidation) --> attaches carnitine to the FA to form FA-carnitine 3. FA-carnitine comes inside and then FA acyl-CoA forms which then undergoes Beta oxidation either way both small and large FA go to peroxisomes or mitochondria to do Beta oxidation
can glutamine be involved in ionic interactions?
no salt bridges are only between KEDRH
are G cells only in pyloric glands?
no they can also be found in gastric glands (but mainly in pyloric)
do prokaryotes have histones and telomeres?
no!!! telomerase only for eukaryote archae have histones
what is the reverse of a spontaneous reaction?
non spontaneous
Are interferons specific or non-specific?
non-specific mainly but it also can be adaptive (specific) proteins that prevent viral replication and dispersion slow down and stop virus spreading
nonreducing vs reducing sugars have what bound?
nonreducing sugars have something bound at anomeric C (glycosidic bond formed) reducing sugars have OH bond
Where are ribosomes made?
nucleolus (nucleoli) nucleolus makes rRNA which make ribosomes which leave the nucleus via nuclear pores to go to the cytoplasm
how many axons can oligodendrocytes myelinated vs schwann cells?
oligodendrocytes (CNS) can myelinate multiple axons while schwann cells (PNS) can only myelinate 1 axon at a time
primary vs secondary active transport
primary: directly uses ATP (ATP hydrolysis- releases E) secondary: coupled; molecules passively moving ALONG concentration gradient releases E which is used to move molecules AGAINST their concentration gradient (PE stored from one drives another)
Are prokaryotes (bacteria) unicellular or multicellular? what about eukaryotes?
pro- all are unicellular eukaryote- both ex. protists are unicellular; mammals, plants, fungi, algae multicelluar
do prokaryotes or eukaryotes make proteins faster?
prokaryotes because in eukaryotes transcription and translation happen in steps but in prokaryotes it happens simultaneously the polymerases in prokaryotes also act faster
if we are told that something is a prosthetic group, what can it tell us about the affinity?
prosthetic groups are tightly bound to enzymes usually through covalent bonds so we know that it would have a LOWWWW kd so high affinity for the enzyme
what makes up ribosomes?
proteins and rRNA ribosomal proteins are made in the cytoplasm and then they go into the nucleus to combine with rRNA to make ribosomal subunits to form ribosome rRNA is in the nucleolus (nucleoli) --> made via transcription via RNA polymerase 1
proteins vs DNA size stain gel
proteins are much smaller than DNA protein stain via coomassie blue or silver stain & DNA with fluorescence to glow protein uses polyacrimide gel (highly cross linked) while DNA uses agarose gel (large pores)
The fact that there appears to be a genetic component to inflammatory bowel disease, but that it does not show clear Mendelian inheritance ratios suggests any of the following, EXCEPT: A. the gene for the disease has incomplete penetrance B. the gene for the disease has limited expressivity C. the disease is polygenic D. the gene for the disease is recessive
read Q carefully! Inflammatory bowel disease appears to have a genetic component, but it does not show clear evidence of Medelian inheritance. This means that the trait cannot simply be "recessive" since, if it were, it would show Mendelian inheritance patterns. Mendelian inheritance patterns: dominant and recessive genes
RT-PCR (reverse transcriptase-polymerase chain reaction)
reverse transcriptase turns mRNA into cDNA (single stranded) & then it is amplified to make thousands of DNA -- primer is added to cDNA to make it go from ssDNA to dsDNA cDNA is denatured into single strands and the add forward and reverse primers to anneal denatured cDNA so Taq polymerase can elongate DNA sequence different genes are expressed during specific stages of development (blastula vs gastrula) and in different parts of the body like lizard's tail vs tongue -- so by taking mRNA for different regions of the body we can make DNA and then see that different genes are expressed
what direction do ribosomes read vs polymerases?
ribosomes 5' --> 3' polymerases 3' --> 5' (synthesize 5' to 3')
what can easily disrupt salt bridges?
salts because salts are made up of + and - charge so they can go and bind to the + and - charges on salt bridges which would disrupt the interaction between them ex. NaCl --> Na+ goes and binds to the negative charge of the salt bridge (so like D or E) and Cl- goes and binds to the positive charge (like KRH) cause proteins to unfold (denature) and lose or reduce function
what kind of amine is in proline?
secondary all the other amines are primary (unless its bound with other substrates so make sure to double check)
how can dehydration affect the kidneys?
severe dehydration greatly reduces the volume of filtrate moving through the nephrons of the kidney -- because you're going to want to keep as much water in as possible If fluid volume is too drastically reduced, the kidney will be unable to effectively do its job of filtering and maintaining homeostasis within
What is the cooperativity of sigmoidal and hyperbolic curves?
sigmoidal curves indicate cooperativity but with hyperbolic curves there is NOT POSITVE cooperativity with hill's coefficient: n>1 = positive cooperativity (sigmoidal) n<1 = negative coopeartivity (hyperbolic- lower on graph than no cooperativity) n=1 - no cooperativity (hyperbolic)
describe how transcription factors are associated with the nucleus AND the cytoplasm?
since TFs are proteins, they are made in the cytoplasm but they control gene expression so they go back into the nucleus and exert their affects localization in the nucleus
diastole and systole mnemonic
sky/dirt systole/diastole heart beating bc bird is flying/resting on dirt
At the end of his initial hospital stay, a few E. coli cells remained in the patient's colon, even though he was taking antibiotics. These cells were most likely present because: A. the antibiotics cause drug-resistance mutations to occur in the bacterial DNA B. the bacteria in the patient developed an immune reaction to the antibiotics C. the patient's colon cells became increasingly resistant to the antibiotics during his hospitalization D. chance mutations in a few E.coli before the treatment made these cells and their descendants antibiotic resitant D.
so antibiotics would not cause mutations so we can get rid of A bacteria don't develop an immune reaction to antibiotics so we can get rid of B C can be eliminated because the relationship between colon cells and antibiotics does not explain the relationship between antibiotics and bacteria -- also it is the bacteria that become resistant, not the colon cells D correct because mutations can cause bacteria to become resistant to antibiotics -- these types of mutations are rare but these mutations can happen and cause the bacteria to flourish when nonresistant cells are being killed by antibiotics
once F+ transfers plasmid to F- are the bacteria now the same?
so bacteria already have their own chromosomes so they're their own thing.... then F+ with the F-factor or fertility factor creates an appendage or a sex pilus which connects to the F- bacteria the plasmid starts off double stranded and then unwinds into two strands... the tDNA travels to the other bacteria and then the DNA in both bacteria replicate to form dsDNA so now the F- becomes F+ bc now it has a plasmid so we have 2 F+ bacteria... they have identical plasmids but they are made up of different chromosomes (DNA) https://www.youtube.com/watch?v=hm8SZaFmlWg
Table 1 lists concentrations of various solutes in normal plasma, in plasma from a typical renal failure patient before dialysis, and the range of solute concentrations used in dialysate solutions. Sodium (Na+): normal plasma: 140 mEq/L renal failure: 138 mEq/L Dialyste range: low --> 128 mEq/L high -->140 mEq/L Why are high concentrations of sodium included in the dialysate (Table 1)? A. to induce water movement from the blood into the dialysate fluid B. to maintain a high osmotic pressure in the diasylate solution C. to maintain isotonicity of the dialysate solution with blood D. to compensate for the urea nitrogen and creatinine in the blood
so if you analyze the table carefully- you can see that normal plasma is 140 mEq/L while dialysate at high concentration is 140 mEq/L that means that they have the same concentration -- so ISOTONIC A is wrong because if the concentrations are the same, then water will not be moving from blood into the diasylate fluid due to sodium concentration C- wrong bc there isn't a high osmotic pressure if the concentrations of sodium are the same The question asks the examinee to correctly identify the reason why high concentrations of sodium are included in the dialysate. As shown in Table 1, the dialysate contains 128-140 mEq/L of sodium, which is equivalent to the sodium concentration in normal plasma, as well as to the sodium concentration in the blood of a patient with renal failure. Consequently, A is incorrect because solvent will not move in response to the sodium concentration in the dialysate, if it is the same as the concentration in the patient's blood. B is incorrect because the sodium in the dialysate is not maintaining a high osmotic pressure if the patient's blood and the dialysate have the same sodium concentration. C is correct because examination of the concentrations of all ions in plasma and dialysate suggests that sodium levels must remain high in the dialysate so that the dialysate is isotonic to blood. D is incorrect because the sodium concentration of the dialysate would not compensate for the levels of urea nitrogen and creatinine nitrogen in the blood. Thus, C is the best answer.
why does ammonia excretion increase when we are starving?
so when we are starving we run out of carbs and fats to break down for energy but we still have protein present so our body begins to breakdown protein --> AAs which increases ammonia excretion
How do adrenergic drugs affect digestion?
so when you see adrenergic - NE,E -- fight or flight so it would want to decrease digestion and peristalsis by inhibiting those enzymes would want to increase nutrient absorption so that we are able to get nutrients to muscles and organs for use -- would want to dilate blood vessels to help with this blood flow Symp NS- typically does vasoconstriction but some exceptions sympathetic nervous system can accelerate heart rate, widen bronchial passages, decrease motility of the large intestine, constrict blood vessels, increase peristalsis in the esophagus, cause pupillary dilation, piloerection (goose bumps) and perspiration (sweating), and raise blood pressure
What are mutations caused by?
some mutations seem to happen spontaneously without any outside influence (randomly) They occur when mistakes are made during DNA replication (even mitosis, meiosis, or protein synthesis)/other mutations are caused by environmental factors called mutagens (chemical substance or radiation)
what is the essential part of the plasma membrane of RBCs?
sphingolipids they are important for structure
what is the role of spleen and lymph nodes with WBC?
spleen: WBC remove pathogens and remove old/damaged RBC blood filtration WBC recognize pathogens and bind/mount foreign antigens -- create immune response lymph nodes: like spleen WBC remove pathogens and create immune response against them B and T lymphocytes mount foreign antigens here
REVERSIBLE OR IRREVERSIBLE? spontaneous processes: nonspontaneous processes:
spontaneous processes: irreversible nonspontaneous processes: reversible
what are the nonhydrolizable lipids?
steroids, prostaglandins, fat-soluble vitamins, cholesterol
How does epinephrine work in relation to glucose?
stimulates the release of glucagon because it wants to get glucose to be distributed throughout the body especially during times of emergency It is a vasoconstrictor effect and also increases cardiac output
how many antigens can antibodies bind at a time?
they are specific to one type of antigen but are able to bind 2 antigens at a time (has to be same type)
are ribosomes of prokaryotes and eukaryotes similar or different?
they are very different than eukaryotes (mammals, plants, fungi) this is because prokaryotes are bacteria -- so when we get sick we take antibiotics which go in and target ribosomes in prokaryotes which disrupts translation but it does not alter our eukaryotic ribosomes in any way
Parallel vs. antiparallel β-sheets
they both have H-bonding with the adjacent backbone parallel has a longer sequence (360 degree loop) connecting the N to C terminus --- N terminus' align Have the zig zag H bonding antiparallel beta turns are shorter (180 degrees) -- have the straight H bonding -- antiparallel is more stable bc it has more of an optimal H bonding
How do stacking interactions serve as a stabilizing interaction for proteins?
they happen between aromatic side chains (FWY) which can increase the stability of secondary structures stacking interactions serve as a stabilizing interaction in the DNA double helix as well -- but with bases stacking & two strands run in opposite directions to form the double helix
how do inflammatory cell trigger vasodilation?
they release histamine, bradykinin, and prostaglandin which help dilate blood vessels this allows immune cells to easily travel through the blood stream and get to the damaged site
In eukaryotic cells, the process of incorporating uridine nucleotides into nucleic acid polymers occurs in which of the following structures of the cell? A. Nucleus B. Lysosome C. Ribosome D. Golgi Body Similar question: (2) In which organelle of a eukaryotic cell is the pyrimidine uracil, as part of uridine triphosphate (UTP), incorporated into nucleic acid? A. Nucleus B. golgi bodies C. ribosomes D. endoplasmic reticulum
this type of thing was asked like 3 times.. got it right but KNOW THIS! The correct answer is A. The question asks the examinee to identify the cellular structure in eukaryotic cells in which the process of incorporating uridine nucleotides into nucleic acid polymers occurs. Uridine nucleotides are incorporated into RNA, and the question is therefore asking where transcription occurs. In a eukaryotic cell, transcription occurs in the nucleus (A). Thus, A is the best answer. 2. The correct answer is A. The nitrogenous base, uracil, combined with the sugar ribose and phosphate makes up the nucleotide uridine. It is found in RNA, but not in DNA. The corresponding DNA nucleotide is thymine. Uridine is incorporated into RNA in the nucleus where transcription of DNA into RNA takes place. RNA is manufactured in the nucleus from a DNA template. Therefore, the correct answer is answer choice A. RNA is necessary for protein synthesis by free ribosomes and those attached to endoplasmic reticulum, but it is not synthesized there, so answer choices C and D are incorrect. Proteins are packaged for export in the Golgi apparatus, but it too takes no part in RNA synthesis, so answer choice B is incorrect.
what can mess up elisa method?
too little substrates = insufficient color change -- inaccurately reports low levels of proteins too many substrates = too much color change -- inaccurately reports low levels of proteins color change- it is proportional to protein concentration and it tells us the presence & quantity of proteins
How can the brain and the digestive tract and fat cells communicate when they're so far apart?
via hormones -- released by the hypothalamus of the brain and put into the blood steam (endocrine hormones)
which are faster sleep or wakefulness brain frequencies?
wakefulness because sleep brain frequencies are slower like delta waves
what are the hydrolyzable lipids?
waxes, triacylglycerols, phospholipids, sphingolipids, glycerolipids highlighted are the hydrolyzable bonds lipases cleave the ester bonds in hydrolizable lipids
how does our respiration rate change when we have a fever (or hot)?
we increase our respiration rate to dissipate heat think about how when we work out, we get super hot and we breathe heavily.... dogs panting
salvation layer: folded vs unfolded proteins
we want higher entropy so we want water molecules to be more DISORDERED- we want hydrophobic inside and hydrophilic outside to interact with aqueous environment which is POSITIVE DELTA S unfolded proteins form aggregates and water molecules must form in an orderly manner around them which DECREASES ENTROPY (more ordered) which is unfavorable
what exactly happens to the enzyme when temperature changes?
when temperature is high --> the protein is denatured so enzymes break apart and the active site is destroyed with low temperatures --> the active site is in tact but the active site is inflexible and rigid so the active site cannot easily change shape for the transition state so the reaction will happen slowly
would we want to increase or decrease aldosterone after eating lots of salty food?
would want to decrease aldosterone because aldosterone increases the amount of salt (+water) in our blood stream so if we increase aldosterone then we would further increase blood pressure which is bad we would want to decrease aldosterone so that NaCl can be excreted in urine
can prostaglandins help the immune system?
yes bc it can do autocrine and paracrine signaling which can help with localized inflammatory response
do prokaryotes and eukaryotes have the same cell membrane?
yes they do! made up of phospholipids, cholesterol etc prokaryotes have cell wall while animal cells do not (some eukaryotes have cell walls)
Describe the ELISA process
you add a sample to a well --> antigen (protein) binds and becomes immobilized bc it absorbs to the well then you add antibodies which are specific to the antigen binding is: -direct: when primary antibodies with receptor enzymes bind to the antigen -indirect: primary antibodies bind and then secondary antibodies with receptor enzymes bind to the antigen WASHHH-- get rid of antibodies that are not bound to anything finally add substrates that bind to the receptor which cause a color change --> reaction product causes the color change color change- it is proportional to protein concentration and it tells us the presence & quantity of proteins
how do we increase blood glucose levels if an individual is unresponsive to hormones?
you dont add E or glucagon bc they are hormones you would make the individual consume more sugar like sucrose NOT cellulose bc that is used as fiber and digestion -- our human bodies do not break down cellulose
