Think it would be C, not 100% on this.
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.
Well you should know about a punnet square, so anyways you have the result of the punnet square, if you have a dominant allele then the phenotype would be that allele, while the genotype is the dominant and either a recessive allele or a dominant allele.
C. The digestive system breaks down food and the circulatory system transports the nutrients throughout the body.
The Digestive system is the system that helps the body digest food. It consists of the following organs: liver, stomach, gallbladder, large and small intestines, pancreas, rectum, and esophagus.
The Circulary system is the system that pumps blood through body. The blood contains all the nutrients and minerals the body needs. The system consists of the following organs: heart, blood vessels, blood, lymph, lymphatic vessels, and glands.
Carbon cycle refers to an array of procedures by which the compounds of carbon are interconverted in the environment, comprising the inclusion of carbon dioxide into living tissue by the process of photosynthesis and then getting back into the atmosphere via respiration, the burning of fossil fuels, and the decomposition of dead organisms.
The following are the steps that illustrate how the carbon cycle functions:
1. Carbon enters the atmosphere as carbon dioxide from combustion and respiration.
2. The absorption of carbon dioxide takes place by the producers to manufacture glucose in photosynthesis.
3. The animals feed on the plant passing the carbon components through the food chain. The majority of the consumed carbon is exhaled in the form of CO2, which was produced at the time of aerobic respiration. The plants and animals die eventually.
4. The dead plants and animals get dissociated by the dead organisms and return the carbon present in their bodies back to the atmosphere as CO2 by the process of respiration. In certain occasions, the dead plant and animals get converted into fossil fuel, which is available in future for combustion.
