B)<span>When you listen to the heart sounds, you are hearing the flow of blood which stops abruptly when a heart valve closes. This produces the "lub-dub" sounds. 1st heart sound (when the Mitral Valve closes) as the ventricle contracts (systole) and then 2nd heart sound (when the Aortic Valve closes) and the ventricle starts to fill again (diastole)
</span><span>The pulse is the wave of pressure you can feel through the artery walls. This denotes systole.
</span><span>The ECG's QRS complex is the electrical signal that tells the Ventricles to contract. You can see that the QRS occurs right at the beginning of systole and triggers Isovolumetric contraction.
</span><span>So the QRS on the ECG, the pulse wave you can feel (ie. the rise in aortic pressure) and the 1st heart sound all signify SYSTOLE.
</span><span>there a delay between systole of the ECG and the resulting pulse felt in the finger (R-Pulse) </span>because it takes a little bit of time for the pressure to transmit through the body, as the finger is not on the heart (if it was there would be no delay)
Answer:
In the case of the algae, each individual cell is responsible for absorbing its own water. This makes the algae nonvascular compared to the highly vascular plant species. In this connection, algae also lack several key structures that are normally present in ordinary plants like the leaves, roots and stem.
Answer: Atoms are the basic building blocks of all matter, living and nonliving. They are made up of subatomic particles (neutrons, protons, and electrons)
Explanation:
Hope thats correct and helps! :)
Answer:
The correct option is d. it causes exchange diffusion
Explanation:
Amphetamines are synthetic substances with a stimulating effect. Their action lies mainly in increasing synaptic levels of monoamines by various mechanisms, including diffusion exchange through membrane transporters. Amphetamine increases extracellular concentrations of serotonin by displacing the neurotransmitter from its specific presynaptic transporter. When amphetamine binds to serotonin transporters, on the one hand it prevents it from entering the terminal and on the other it reverses the recapture mechanism so that serotonin leaves the synaptic space.
The raw material from which sedimentary rocks are formed is D. Weathered remains of other rocks.
