Biological and Biochemical Foundations Score 122 Flashcards
What contributes to Cerebal edema?
Cerebral edema is the accumulation of fluid in the brain. Increased cerebral blood flow. Increased cerebrospinal fluid. Increased serum glucose.
What is ketogenesis?
Ketogenesis is the biochemical process through which organisms produce ketone bodies through breakdown of fatty acids and ketogenic amino acids. This process supplies energy under circumstances such as fasting or caloric restriction to certain organs, particularly the brain, heart and skeletal muscle. It can be triggered by a severe insulin deficiency.
What are some common things seen as an effect of diabetic ketoacidosis?
- Decrease in plasma pH
- Increased plasma fatty acid concentration.
- Cells won’t have an accumulation of intracellular glucose
When is NADH most likely used?
NADH is often utilized as a cofactor in both catabolic and anabolic reactions as a hydrogen donor. Look for added hydrogens.
What is the relative risk ratio?
The relative risk (RR) ratio provides us with meaningful information as to whether or not there is an increased risk associated with a given condition and the occurrence of an event. In order to be statistically meaningful, both the RR and lower bound of the confidence interval (CI) must exceed 1
What is the effect of Increasing the osmotic pressure of serum plasma?
Increasing the osmotic pressure of serum plasma (by administration of hypertonic saline) would pull fluid from the brain into the bloodstream where it can be excreted
What is the effect of Increasing cellular electrolyte uptake in central nervous system neurons?
it would increase the osmotic pressure of the intracellular compartment, increasing cellular uptake of electrolytes would most likely increase the accumulation of fluid in the brain
What is the effect of Decreasing generation of ketone bodies?
Administration of insulin will result in the down-regulation of both lipolysis and ketogenesis, decreasing the generation of ketone bodies
What is antigenic?
Antigenic molecules can cause antibody production
What is amphipathic?
Detergents are amphipathic (or amphiphilic) molecules because they are both hydrophilic and hydrophobic
What is Amphoteric?
Amphoteric molecules can act as either acids or bases. Examples of amphoteric molecules are amino acids (due to their amino and carboxyl ends) or bicarbonate (HCO3–) which neutralizes stomach acid in the duodenum and functions as a blood buffer
What is allosteric.?
Allosteric regulators are small molecules that can bind to allosteric sites on enzymes and control their activity
How does E.coli grow best?
37 degrees. If bacteria are growing in liquid culture, they must be continuously shaken to ensure proper mixing and distribution of nutrients, and to provide a constant oxygen supply.
What is a true statement about RNAase?
It contains peptide bonds and is degraded non-specifically in strong acid conditions. RNAase is an enzyme that degrades RNA by breaking the phosphodiester bonds in the RNA backbone. Enzymes are proteins and are therefore made of amino acids connected by a covalent peptide bond. Proteins are degraded specifically by proteases and nonspecifically in strong acid conditions or extreme temperatures. Enzymes increase the rate of the reaction by decreasing the activation energy in a reaction and are not consumed in the reaction, but are regenerated
What does myelination of nerves do?
Myelination speeds up nerve conduction by allowing action potentials to “skip over” myelinated regions of the neuron; these action potentials are instead transmitted between the nodes of Ranvier on the axon. Demyelination due to illness slows nerve conduction enough that a patient would have difficulty contracting the diaphragm. An action potential, once initiated, is “all or none”; it cannot have a large or small amplitude
What does methylation of DNA do?
Methylation of DNA (called imprinting) and methylation of histones with subsequent heterochromatin formation can both silence gene expression
What is RNA interference?
is a posttranscriptional method of regulating gene expression.RNAi is mediated by siRNA (small interfering RNA) or miRNA (micro RNA). These small non-coding RNAs bind to complementary sequences on mRNA and the resulting double stranded RNA is degraded. The reduction in mRNA leads to a reduction in the gene product
What is the promoter region?
the promoter is just the binding site for RNA pol; the start point of transcription is located downstream from the promoter, and typically the regulatory regions for repressor/enhancer binding are between them
What is the boiling point temp of a substance?
The boiling point temperature of a substance is the temperature at which its vapor pressure equals the atmospheric pressure. If the atmospheric pressure is lowered, the substance will boil when its vapor pressure is lower, i.e., at a lower temperature
How can you change an equilibrium constant (K)?
The only way of changing the value of an equilibrium constant, K, and therefore a value like pKb, is to change the temperature
How does the solubility of a gas change when pressure is changed?
The solubility of a gas decreases with decreasing pressure
How is the solubility of a compound affected when Ksp changes?
The solubility of a compound increases as Ksp for that compound increases. More moles of the Zn(OH)2 will be dissolved than Fe(OH)2 in the starting solutions based on Ksp values.
Zn(OH)2 1.8 x 10–14
Fe(OH)2 1.1 × 10–14
What is the dissociation equation for a compound?
M(OH)2(s)—->M^2+(aq)+2OH-(aq)
How would adding NaOH to a solution (looking at dissociation equation) affect the equilibria?
M(OH)2(s)—->M^2+(aq)+2OH-(aq)
When NaOH is added, the OH– concentration is increased and we would expect the equilibria of both solutions to shift to the left as predicted by Le Chatelier’s principle (or the common ion effect).
What is pepsin?
An enzyme made in the stomach that breaks down proteins in food during digestion. Stomach acid changes a protein called pepsinogen into pepsin.
What are serous cells?
Serous cells make serous secretions, which in the salivary gland would include salivary amylase (or ptyalin) and salivary lipase.
What blood cells contain nuclei?
White blood cells contain nuclei and genetic material but not red blood cells.
What is a balanced translocation?
genetic information is neither missing nor added.
What is a Robertsonian translocation?
the parent has the majority of their genome intact, but that the long arm of their chromosome 21 has moved and has attached opposite the long arm of chromosome 14. The short arms of chromosomes 14 and 21 are lost but the passage describes how this has little effect. This would appear on the parental karyotype as a missing chromosome 21 (and an elongated chromosome 14), thus the parent would appear to have only 45 total chromosomes. When this parent has offspring, one possibility is that she will pass on her normal chromosome 21 as well as the Robertsonian chromosome (the 14:21 combination). The father of the child will pass on his normal chromosome 21, and the child will thus inherit three copies of chromosome 21.
What is chimerism?
Chimerism is described as the fusion of two non-identical zygotes early in development, and each differentiates into distinct tissues making up a single fetus. Two non-identical zygotes must have arisen from two eggs that were fertilized by two sperm
What is polyspermy?
Polyspermy is the fertilization of an egg by multiple sperm, and the results of such unions are lethal. If multiple sperm fertilize an egg, the embryo inherits multiple paternal centrioles. This causes competition for extra chromosomes and results in the disruption of the creation of the cleavage furrow, thus causing the zygote to die.
When does nondisjunction occur and what are the effects?
ANAPHASE. If a single nondisjunction event occurred in anaphase II of spermatogenesis, it would only affect two out of the four resulting gametes. The primary spermatocyte would generate two normal secondary spermatocytes. One of the secondary spermatocytes would perform normal anaphase II and would generate two normal spermatids. The secondary spermatocyte that undergoes nondisjunction in anaphase II would produce two abnormal spermatids, one that would fertilize an egg to cause trisomy and another that would fertilize an egg and cause monosomy. Thus, the probability of Down syndrome occurring if nondisjunction occurred in anaphase II of spermatogenesis would be 25%. If the nondisjunction event occurred in anaphase I, both secondary spermatocytes would be affected and all four spermatids would be affected; two would generate zygotes with trisomy and two would generate zygotes with monosomy. Thus, the probability of Down syndrome occurring if nondisjunction occurs in anaphase I is 50%
What does GnRH do and what is it?
Gonadotrophin-releasing hormone. GnRH travels from the hypothalamus to the anterior pituitary to have its effect. The hypothalamus is connected to the anterior pituitary via a portal system, which is a series of two capillary beds placed in sequence. This system allows hormones such as GnRH that have been released into the blood by the hypothalamus to be rapidly taken up by the anterior pituitary before they circulate around the rest of the body, during which time they might degrade. the anterior pituitary does not contain nerve axons from the hypothalamus
How do diabetes drugs work?
When cells are resistant to insulin, glucose stays in the blood. Over time, high blood sugar levels can cause damage to the kidneys, the eyes, and blood vessels, in addition to other side effects. Diabetes drugs work to reduce blood sugar by assisting in the movement of glucose out of the blood and into cells
