Lab quizzes Flashcards
When the brain receives an input signal indicating that the body temperature is too high it sends an output signal through sympathetic nerves that activates sweat glands in the skin. Sweating helps to lower body temperature. What type of control mechanism is this?
Extrinsic control in negative feedback
What component of a homeostatic control mechanism detects the change in a variable produced by a stimulus?
Receptor (Sensory)
What role do sweat glands play in a homeostatic control mechanism for thermoregulation?
Effector
The uterus contains an inner lining of epithelial tissue the functions to nourish the developing fetus and a thick outer layer of smooth muscle that functions to produce uterine contractions during childbirth. What level of biological organization is the uterus?
Organ
During childbirth afferent neurons relay information into the brain from cervical stretch receptors in the uterus. Increased stretching stimulates production of the hormone Oxytocin. Oxytocin stimulates uterine contractions leading to increased stretching until the baby is delivered. What type of control mechanism is this?
Extrinsic control in positive feedback
What is the study of the functional changes in disease?
Pathophysiology
What type of bond forms between the partial negative charge of an oxygen atom in one molecule of water and the partial positive charge of a hydrogen atom in a different molecule of water?
Hydrogen bond
What type of bond forms between the oxygen and hydrogen atoms within a molecule of water?
Polar covalent bond
Polar molecule like glucose (C6H12O6) an ions like sodium (Na+) and chloride (CL-) are ________ chemicals that dissolve easily in water.
Hydrophilic
What variable does the experimenter manipulate in an experiment to investigate the effects on another variable? For example, what variable is the dietary vitamin D level in an experiment testing the effects of vitamin D on growth?
Independent Variable
A strong vinegar solution with a pH of 2.0 has __________ the concentration of hydrogen ions found in a neutral solution with a solution with a pH of 7.0?
100,000 times
Glycolysis is a catabolic pathway that converts glucose (C3H4O3). The atomic weight of carbon is 12 grams per mole. The atomic weight of hydrogen is 1 gram per mole. The atomic weight of oxygen is 16 grams per mole. What is the molecular weight of pyruvic acid?
88 g/mole
A recent study published by scientist at Stanford University School of Medicine demonstrated that the modern value of the homeostatic setpoint for body temperature is about 97.9 degrees Fahrenheit (F). What is this temperature in degrees Celsius (C)?
Formula: (F-32)5/9=*C
36.6 *C
How many grams of sodium chloride (NaCl) would be needed to make 5000L of a 0.90% isotonic saline solution?
(Formulas: 1% solution= 1g/100mL, 1Liter= 1000mL)
4.5x10^4 g
The molecular weight (M.W.) of sodium chloride (NaCl) is 58.5 g/mole. Calculate the molarity of a 0.90% isotonic saline solution. (Formulas: 1% solution=1g/100mL, 1 Liter=1000mL, Molarity (M)=moles/liter=grams/liter divided by M.W.)
0.15 M
Which direction does water move by osmosis if an erythrocyte is place in a hypertonic solution of 5% sodium chloride?
Out of the ell
Which direction does water move by osmosis if an erythrocyte is placed in a hypotonic solution of 0.009% sodium chloride?
into the cell
Which solution has the same solute concentration as the cytosol?
Isotonic solution
If you increase the temperature of a solution, the rate of diffusion?
Increase
What molecules have the fastest diffusion rate through an aqueous solution like the cytosol or blood plasma?
Molecules with low molecular weight diffuse faster when comparing heavier molecules molecular weight.
What method was used to separate DNA molecules for restriction fragments length polymorphism (RFLP) analysis?
Gel Electrophoresis
What nucleotide in DNA forms a Complementary base pair with Thymine?
Adenine
What membranous organelle sorts newly made proteins coming from the rough endoplasmic reticulum and sends them out in transport vesicles to various destinations within the cytoplasm, plasma membrane, or extracellular fluid?
Golgi apparatus
What amphiphilic organic molecules from a bilayer in the plasma membrane ?
phospholipids
What organelle performs translation to synthesize proteins?
Ribosome
Which organelle performs oxidative phosphorylation to produce large amounts of ATP?
Mitochondria
Where does transcription occur?
Nucleus
Which active transport mechanism moves extracellular fluid into the cell forming a vesicle within the cytoplasm?
Pinocytosis
What type of membrane transport mechanism enables a sodium ion to move into the cytosol through a channel protein from extracellular fluid with a higher sodium concentration?
Faciliatated diffusion
What chemical is broken down by the sodium-potassium pump in order to provide the energy needed to drive primary active transport of sodium?
Adenosine Triphosphate (ATP).
What molecules function as biological catalysts that speed up chemical reactions without being used up or altered in reaction?
Enzymes
What is a function of tyrosinase in humans?
Production of the pigment melanin
What determines the specificity of an enzyme?
The amino acid sequence of the protein
How does increasing the concentration of the substrate catechol effect the rate of the reaction catalyzed by catechol oxidase
Increase
How does decreasing the concentration of catechol oxidase effect the rate of formation of the product benzoquinone?
Decrease
What is a molecule that slows the rate of a biochemical reaction by binding to the active site of an enzyme?
Competitive inhibitor
What mechanism causes a dramatic decrease in enzyme activity at extremely high temperatures?
Denaturation
What type of RNA carries amino acids to the ribosome during translation?
tRNA
What transport mechanism is the movement of glucose into the cell against its concentration gradient that is fueled by the movement of sodium into the cell down its concentration gradient through a sodium-dependent glucose cotransporter?
Secondary Active transport
During which phase of mitosis do chromosomes align in the center of the mitotic spindle?
Metaphase
During which phase of the cell cycle is DNA replicated?
S phase
During transcription, what enzyme catalyzes dehydration synthesis of nucleotides to form a RNA polymer?
RNA polymerase
During the initiation step DNA replication, which enzyme constructs RNA primers complementary to the sequence of the template strand?
Primase
What genes code for proteins that normally stop or slow down the cell cycle and stimulate DNA repair?
Tumor suppressor genes
How does pH affect enzyme activity?
Increasing or decreasing from the optimal pH decreases activity.
