Answer:
This electrical signal start in the sinoatrial node generates an electrical impulse. From this, the signal passes through the atrioventricular node, which stops the signal for a brief moment and sends it through the muscle fibers of the ventricles, stimulating its contraction.
Explanation:
The electrical impulses generated by the myocardium stimulate the heartbeat. This electrical signal originates in the sinoatrial node located in the upper part of the right atrium. When the sinoatrial node generates an electrical impulse, it stimulates the contraction of the atria. From this, the signal passes through the atrioventricular node, which stops the signal for a brief moment and sends it through the muscle fibers of the ventricles, stimulating its contraction.
I would say the answer is All of the above
Answer:
a
Explanation:
Smoking causes cancer, heart disease, stroke, lung diseases, diabetes, and chronic obstructive pulmonary disease (COPD), which includes emphysema and chronic bronchitis. Smoking also increases the risk of tuberculosis, certain eye diseases, and problems with the immune system, including rheumatoid arthritis.
Other effects of tobacco smoke on the body include:
- irritation and inflammation of the stomach and intestines
- increased risk of painful ulcers along the digestive tract
- reduced ability to smell and taste
- premature wrinkling of the skin
- higher risk of blindness
- gum disease (periodontists).
The effects of tobacco smoke on the musculoskeletal system include:
- tightening of certain muscles
- reduced bone density.
The effects of tobacco smoke on the immune system include:
- greater susceptibility to infections such as pneumonia and influenza
- more severe and longer-lasting illnesses
- lower levels of protective antioxidants (such as vitamin C), in the blood.
The effects of tobacco smoke on the circulatory system include:
- raised blood pressure and heart rate
- constriction (tightening) of blood vessels in the skin, resulting in a drop in skin temperature
- less oxygen carried by the blood during exercise
- ‘stickier’ blood, which is more prone to clotting
- damage to the lining of the arteries, which is thought to be a contributing factor to atherosclerosis (the buildup of fatty deposits on the artery walls)
- reduced blood flow to extremities (fingers and toes)
- risk of stroke and heart attack due to blockages of the blood supply.
The effects of tobacco smoke on the respiratory system include:
- irritation of the trachea (windpipe) and larynx (voice box)
- reduced lung function and breathlessness due to swelling and narrowing of the lung airways and excess mucus in the lung passages
- impairment of the lungs’ clearance system, leading to the buildup of poisonous substances, which results in lung irritation and damage
- and increased risk of lung infection and symptoms such as coughing and wheezing
- permanent damage to the air sacs of the lungs.
Highly damaging components of tobacco smoke include:
- Tar– is the word for the solid particles suspended in tobacco smoke. The particles contain chemicals, including cancer-causing substances (carcinogens). Tar is sticky and brown, and stains teeth, fingernails, and lung tissue
- carbon monoxide – is a poisonous gas. It is odorless and colorless and, in large doses, quickly causes death because it takes the place of oxygen in the blood. In people who smoke, the carbon monoxide in their blood makes it harder for oxygen to get to their organs and muscles
- oxidizing chemicals – which are highly reactive chemicals that can damage the heart muscles and blood vessels of people who smoke. They react with cholesterol, leading to the buildup of fatty material on artery walls. Their actions lead to heart disease, stroke, and blood vessel disease
- metals – tobacco smoke contains several metals that cause cancer, including arsenic, beryllium, cadmium, chromium, cobalt, lead, and nickel
- radioactive compounds – tobacco smoke contains radioactive compounds that are known to be carcinogenic.
People who use e-cigarettes are more likely to experience side effects such as:
- Coughing.
- Dizziness.
- Dry mouth or a scratchy throat.
- Headaches.
- Loss of taste or changes in taste.
- Shortness of breath.
