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)
I'm gonna say D is the answer.
Stamen: The pollen producing part of a flower, usually with a slender filament supporting the anther. Anther: The part of the stamen where pollen is produced. Pistil: The ovule producing part of a flower. The ovary often supports a long style, topped by a stigma.
Answer:
The correct answer is ecological isolation.
Explanation:
The condition when two species in spite of living in the same region, exhibits certain characteristics, which inhibits them from mating with each other is termed as reproductive isolation. The obstructions or the causes that prevent them from interbreeding is known as isolating mechanisms.
The given case is an example of ecological isolation and is one of the forms of reproductive isolation. Habitat or ecological isolation refers to the phenomenon in which two species cannot mate with each other as they thrive in two distinct locations. Like as mentioned, two species of garter snakes though coming from the same geographical area cannot interbreed, as one of them is living in the land and the other one in the water.