Because the AV node takes on the role of a very important delay in the cardiac conduction system. Without this delay, the atria and ventricles would contract at the same time.
<h3>Cardiac conduction system</h3>
The conduction system of the heart sends electrical signals, usually generated by the sinus nodes, causing the heart muscle to contract. Pacemaker signals originating from the sinus node travel through the right atrium to the atrioventricular (AV) along the bundle of His and through branches of the bundle, causing myocardial contraction. This signal first stimulates contraction of the right and left atria then flows to the right and left ventricles. That electric current then allows blood to be pumped throughout the body.
Learn more about sequence of travel by an impulse through the cardiac conduction system at brainly.com/question/28269433
#SPJ4
Answer:
yes
Explanation:
it will cost less to raise very productive animals because the money that would have been spent on treating infections would be put into a more productive venture
Answer:
A) Times of major climate change
Explanation:
The geological time scale is based on major changes in Earth's climate history. This is because of the reason that climate governs the geological processes on Earth. In geology, we study the ages with the help of stratigraphical data where sediment deposition and the fossils it is hosting are the keys to understand the environmental conditions at that particular time. These conditions didn't change significantly unless the climate was changed. An example is the extinction of dinosaurs during K/T boundary event (mass extinction). The most likely reason is the hitting of a meteorite on Earth that changed the climate of Earth in a short period making it least favorable for many organisms to survive.
On the other hand, the occurrence of huge events cannot be used to establish a geological time scale because sometimes, the changes happen more slowly.
Similarly, shifts in the Earth orbits are cyclic however geological time scale doesn't reflect cyclic changes. The same climate can establish in different ages but these events are not used not as a criterion to establish a geological time scale.
In the end, the time span of humans on Earth is very small when compared with the overall geological time scale. Humans record exists from Pleistocene (2,580,000 to 11,700 years ago) to today whereas geological time scale starts in the Archean Eon (4.0 billion to 2.5 billion years ago).
The question is incomplete as it does not have the options which are:
resistant
semisynthetic
synthetic
natural
Answer:
Semisynthetic
Explanation:
Antibiotics are the microbial compounds which are obtained from the micro-organisms which are found effective against the bacteria as they act by inhibiting the activity of the bacteria which ultimately kills the bacteria.
These antibiotics can also be distinguished based on their synthesis: natural, semi-synthetic and synthetic antibiotics.
The semi-synthetic antibiotics are the antibiotics which are obtained from the microbes but are modified artificially by making chemical changes to increase the effectiveness of the antibiotic and making the antibiotic as broad-spectrum bacteria.
Since the properties of the antibiotics provided in the question are similar to the semi-synthetic antibiotics, therefore, is considered semi-synthetic bacteria.
Thus, Semisynthetic is correct.
