Answer the following question given this paragraph: 19.2 Cardiac Muscle and Electrical Activity The heart is regulated by both neural and endocrine control, yet it is capable of initiating its own action potential followed by muscular contraction. The conductive cells within the heart establish the heart rate and transmit it through the myocardium. The contractile cells contract and propel the blood. The normal path of transmission for the conductive cells is the sinoatrial (SA) node, internodal pathways, atrioventricular (AV) node, atrioventricular (AV) bundle of His, bundle branches, and Purkinje fibers. The action potential for the conductive cells consists of a prepotential phase with a slow influx of Na+ followed by a rapid influx of Ca2+ and outflux of K+. Contractile cells have an action potential with an extended plateau phase that results in an extended refractory period to allow complete contraction for the heart to pump blood effectively. Recognizable points on the ECG include the P wave that corresponds to atrial depolarization, the QRS complex that corresponds to ventricular depolarization, and the T wave that corresponds to ventricular repolarization. Q: The conductive cells within the heart establish the heart rate and transmit it through the what? Choices: - meiosis - conduction - neurons - myocardium A:
myocardium
Answer the following question given this paragraph: Red litmus paper turns blue when placed in a basic solution. Q: Red litmus paper turns what color when placed in a basic solution? Choices: - white - orange - pink - blue A:
blue
Q: Answer the following question given this paragraph: The yellow subunits are identical in structure, as are the gray subunits. A smaller organic structure called a porphyrin ring is attached to each protein subunit and contains the iron ion used to bind oxygen. Q: The iron ion used to bind oxygen is on what type of "ring"? Choices: - DNA ring - petrarchan ring - reagent ring - porphyrin ring A:
A: porphyrin ring
Question: Answer the following question given this paragraph: Stomata are special pores that allow gasses to enter and exit the leaf. Q: Stomata are special pores that allow gasses to enter and exit what? Choices: - the skin - the flower - the soil - the leaf A:
Answer: the leaf
*Question*
Answer the following question given this paragraph: Figure 10.43 Diamond is extremely hard because of the strong bonding between carbon atoms in all directions. Graphite (in pencil lead) rubs off onto paper due to the weak attractions between the carbon layers. An image of a graphite surface shows the distance between the centers of adjacent carbon atoms. (credit left photo: modification of work by Steve Jurvetson; credit middle photo: modification of work by United States Geological Survey) You may be less familiar with a recently discovered form of carbon: graphene. Graphene was first isolated in 2004 by using tape to peel off thinner and thinner layers from graphite. It is essentially a single sheet (one atom thick) of graphite. Graphene, illustrated in Figure 10.44, is not only strong and lightweight, but it is also an excellent conductor of electricity and heat. These properties may prove very useful in a wide range of applications, such as vastly improved computer chips and circuits, better batteries and solar cells, and stronger and lighter structural materials. The 2010 Nobel Prize in Physics was awarded to Andre Geim and Konstantin Novoselov for their pioneering work with graphene. Q: Diamond is extremely hard because of the strong bonding between ______ in all directions? Choices: - consistent atoms - hydrogen atoms - liquid atoms - carbon atoms A:
**Answer**
carbon atoms
(Question)
Answer the following question given this paragraph: A very important point here is that the vertical motion of these two balls is identical. That is, they each fall exactly the same distance vertically in each succeeding second. The constant horizontal velocity of the blue ball has no effect on its accelerated vertical motion. Therefore, the vertical motion of the blue ball can be analyzed exactly the same as the vertical motion of the red ball. Q: What force pulls bodies with mass together? Choices: - thermal - solar - isolation - gravity A:
(Answer)
gravity