What happens in meiosis during anaphase I?

View the animation below, then complete the quiz to test your knowledge of the concept. conducting of the heart

valina [46]

1. In the heart, an action potential originates in the (E) sinoatrial node.
The cardiac action potential is a term referring to the change in the membrane potential of heart cells causing the heart to contract. Cardiac action potentials are created by a group of specialized cells capable of generating automatic action potentials and are located in the right atrium of the heart. These cells are called sinoatrial node and sometimes are referred to as the natural pacemaker of the heart. This characterization originates from the fact that sinoatrial node continuously provides action potential and sets the rhythm of the heart function.

2. The sequence of travel by an action potential through the heart is (A) sinoatrial node, atrioventricular node, atrioventricular bundle, bundle branches, Purkinje fibers.
As explained above, the cardiac action potential originates from the sinoatrial node. This action potential then travels through the atrioventricular node, which belongs to the electrical conduction system of the heart and is located between the atria and the ventricles. It is responsible for the electrical connection between the right atrium and the right ventricle. The action potential then travels to the atrioventricular bundle (or bundle of His), another part of the electrical conduction system of the heart. The atrioventricular bundle transmits the electrical impulses from the atrioventricular node to the bundle branches. The bundle branches then send the signal to the Purkinje fibers which send the electrical impulses to the ventricles, causing them to contract.

3. The correct answer is A.
The generation of an action potential in the sinoatrial node causes the contraction of the atria. When the action potential passes from the sinoatrial node to the atrioventricular node, it slows down. This causes the transport of the electrical impulse from the atria to the ventricles to slow down. This delay enables the blood (from the contraction of the atria) to fill the ventricles before their contraction.

4. This statement is true.
The interventricular septum is a structure which divides the two ventricles of the heart and it is composed of two branches, the left bundle and the right bundle branch. When the action potential reaches the interventricular septum, it then travels to the apex of the heart from where it travels upwards along the walls of the ventricles and the ventricular contraction begins.

5. This statement is true.
The bundle branches gradually become Purkinje fibers located in the interior of the ventricular walls. Purkinje fibers are specialized cells and are responsible for conducting cardiac action potentials from the bundle branches to the ventricular walls. This signal transduction causes the muscle of the ventricular walls to contract.

7 0

3 years ago

The visual examination of the fundus of the eye with an ophthalmoscope is known as?

den301095 [7]

Answer:

Ophthalmoscopy, also called funduscopy.

6 0

2 years ago

Which theory explains why our universe is structured and uniform and suggests that the universe is flat in shape?

snow_lady [41]

Inflation theory is the correct answer.

4 0

3 years ago

Temperature decreases at high altitude

spin [16.1K]

Answer:

Higher the altitude, the thinner the atmosphere gets. The total heat content of a system is directly related to the amount of matter present, so it is cooler at higher elevations.

Here cooler means decrease in temperature.

5 0

2 years ago

List and briefly describe the chemical sequence of events in the fight-or-flight response to a threatening situation from the bi

777dan777 [17]

Answer:

Binding taking place at the receptor site

G protein activates in the cell membrane

Conversion of GDP → GTP

Activation of adenylate cycles

Cyclic production of AMP → ADP

Initiation of the desired reaction in regard to the original message

Cyclic restoration of AMP → ATP

Explanation:

The description of the mechanism:

Right off the bat, epinephrine attaches to a molecule called a receptor (beta-adrenergic protein).

G protein, which is found on the inner side of the plasma membrane, is activated when epinephrine binds to it.

The GDP-carrying Alpha subunit of G protein is isolated during activation. After that, the GDP is translated to GTP.

Adenylate cyclase is then activated by GTP.

The only enzyme that can catalyze the transformation of ATP to CAMP is adenylate cyclase (Cyclic adenosine monophosphate). As a result, the CAMP molecule (secondary messenger) is produced.

CAMP stimulates protein kinase A, and the cycle repeats till the glycogen phosphorylase enzyme is triggered.

After that, the cyclic amp is brought back and restored.

3 0

3 years ago