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Chapter Goals:
- Find the integrated structure and function of the cardiorespiratory system.
- Be able to know the categories of the basic structure and function of the endocrine system.
- Make a summary of the basic structure and function of the digestive system.
The Cardiorespiratory System
This cardiorespiratory system is made up of two systems: the respiratory and the cardiovascular system.
The cardiovascular system comprises the heart, blood vessels, blood, and related parts.
The respiratory system is made up of the airways and the lungs.
These systems work together to give the body the oxygen it needs, deliver the necessary nutrients, and remove waste products from the body, like carbon dioxide.
The Cardiovascular system
This system comprises the heart, blood, and blood vessels in the body to transport blood to the body’s tissues.
The Heart
The heart is a pump for the body that pushes blood. It does so through rhythmic contractions.
The heart is made of cardiac muscle. The Cardiac is similar to the skeletal muscle, except it is a voluntary muscle we have no control over.
The heart is broken down into two atria and two ventricles, one of each on both the right and left sides.
The right side of the heart receives the oxygen poor blood and then sends it through the pulmonary circuit to put oxygen in and take the carbon dioxide out. The left side, then, of course, takes care of the pumping of the newly oxygenated blood and continues the cycle.
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The cardiac muscle fibers are shorter and more tightly connected than that the normal skeletal muscles. There is also a presence of irregularly shaped bands known as intercalated discs.
The resting heart rate for the general population is usually between 60 and 100 beats per minute. The body changes this rate to meet the demands that are placed on it.
The heart is known for its electrical conduction system, which is made of specialized cells that transmit the signal using different nodes in the heart. This allows for the rhythmic contractions to go through their normal pattern, but possibly at different speeds when needed.
The stroke volume is the amount of blood that is pumped out of the heart with all of the contractions.
The stroke volume with the heart rate gives the cardiac output, which is the amount of blood that is pumped out every minute by the heart.
A good idea with exercise is to monitor the heart’s activity and all of these factors using a heart rate monitor.
Blood
This unique life-sustaining fluid will supply the body’s organs and cells with the nutrients and oxygen needed to regulate the body’s temperature, fight off infections, and take out the waste items that accumulate.
The three kinds of cells to know are red blood cells, white blood cells, and platelets.
The support mechanisms of blood are transportation, regulation, and protection.
Blood Vessels
The vessels are a closed circuit of hollow tubes that allow the blood to transport to and from the heart. The three main blood vessel types are the arteries, capillaries, and veins.
The arteries are used to carry the blood from the heart.
The capillaries are used as exchange sites for the water and many other chemicals to go between the blood and the tissues.
The veins are used to carry the blood back to the heart to go through the whole cycle of events again.
The Respiratory System
This system is also known as the pulmonary system and it is used to bring oxygen into the lungs from the air we breathe and to expel the carbon dioxide back into the air when we exhale.
The parts of this system are the airways, the lungs, and the respiratory muscles used.
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Mechanisms of Breathing
Breathing is the process of moving air in and out of the body. This requires the use of the respiratory pump and the accompanying components.
Inspiration and expiration are the two phases of breathing. Inspiration is taking in the air, and expiration is the opposite.
Cardiorespiratory System Function
Oxygen is essential for life, so the cardiorespiratory system is an important part of our lives.
While the cells are using oxygen, they produce carbon dioxide, which needs to be removed. This leads to the inhalation and exhalation processes.
The amount of oxygen consumed depends on the system’s ability to collect oxygen, the system’s ability to absorb and transport the oxygen, and the tissues’ ability to use said oxygen.
Some metabolic processes need oxygen to supply energy for actions, and others do not require it. This is important to know for clients and losing weight.
The Endocrine System
Endocrine literally means “secreting hormones.”
The endocrine stem makes hormones, which are used to affect every form of human function. Some of the big ones are triggering muscle contractions, synthesizing fats, and activating enzyme systems. There are many others we could name.
The endocrine system regulates a wide variety of bodily functions like controlling mood, development and growth, metabolism, and functions of tissues.
All hormones have to target certain cells; thus, they will not interact with just anything they run into.
Endocrine Glands
The main glands of the endocrine system are the hypothalamus, pineal gland, pituitary, adrenal, thyroid, pancreas, and reproductive glands.
Insulin, Glucagon, and the Control of Blood Glucose
Carbs make up the main energy sources during vigorous exercise. They are also the source of energy for the brain.
Insulin is used to help with the regulation of the metabolism in the body, and it does so mainly by telling what substrates for the body to use as fuel and whether the body is well fed or in a fasted state.
Glucagon is one of two hormones that the pancreas secretes, and it is used to regulate blood glucose levels and is considered a counterpart to insulin.
Adrenal, Pituitary, and reproductive Hormones
The adrenal and pituitary glands fill in many of the body’s functions, mainly anything from metabolism to growth and recovery.
The two catecholamines are epinephrine and norepinephrine. The hormones help the body to prepare for activity. These hormones are also known as the fight-or-flight hormones.
Cortisol is a catabolic hormone, which means it has a role in breaking down tissues. It is known as a hormone of stress but also has a role in gluconeogenesis.
Testosterone and estrogen are the reproductive hormones to know. Testosterone is known for its role in the growth and repair of tissues. Estrogen is made in the ovaries and has small levels in the adrenal glands for men.
Growth hormone is known for its role in developing bone, muscle, and protein. It is vital for the body.
Thyroid Hormones and Insulin-Like Growth Factors
The thyroid gland is found in the neck region toward the front, and it releases hormones through the blood to control many functions in almost every organ throughout the body.
Sleep and Its Effect on Hormones
Sleep is a physiological process, and changes in the requirements of this activity throughout the stages of our lives and our fitness levels.
According to studies, most adults will sleep for only 5 – 6 hours, but truly they need an additional 2 on top of that.
Sleep plays a large role in the hormones in the body.
The Digestive System
This complex group of anatomical structures will allow the foods we eat and liquids we consume to be processed, digested, and absorbed.
Overview of the Digestive System
The digestive system has three regions that we group activities into.
The first region is the head and neck, including the mouth.
The second region is the upper gastrointestinal tract.
The third and final region is the lower GI tract.
The food we eat will pass through this exact sequence and digest in various parts depending on the nutrient in question. It is important to know that all nutrients digest in different areas and go through different steps to get to the state needed for use in the body.
As we go through the nutrient chapters, we will discuss the parts of the digestive system that we would use and for what.
Tyler Read
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