BIO theme 3- what causes stress?

Stroke:

A stroke occurs when the blood supply to part of your brain is interrupted or reduced, depriving brain tissue of oxygen and nutrients. Within minutes, brain cells begin to die. A stroke may be caused by a blocked artery (ischemic stroke) or the leaking or bursting of a blood vessel (hemorrhagic stroke). Some people may experience only a temporary disruption of blood flow to the brain (transient ischemic attack, or TIA) that doesn't cause permanent damage.

somatic nervous system

A subdivision of the peripheral nervous system. Enables voluntary actions to be undertaken due to its control of skeletal muscles

What's the role of epinephrine (aka adrenaline) in this process?

Adrenaline stimulates the nerves in the sympathetic nervous system, causing heart rate to increase

Describe the short term effects of adrenaline and cortisol on the body. How does this help us respond to a stressor? (alarm response)

Alarm reaction describes the body's immediate reaction upon facing a threatening situation or emergency, and it is roughly analogous to the fight-or-flight response During an alarm reaction, you are alerted to a stressor, and your body alarms you with a cascade of physiological reactions that provide you with the energy to manage the situation. A person who wakes up in the middle of the night to discover her house is on fire, for example, is experiencing an alarm reaction.

Differentiate between conscious and unconscious control of breathing. What structures are involved? What part of brain is responsible for each?

As part of the brainstem, a section of the lower pons stimulates and controls the intensity of breathing, while a section of the upper pons decreases the depth and frequency of breaths. Medulla - The primary role of the medulla is regulating our involuntary life sustaining functions such as breathing, The behavioral, or voluntary control of breathing is located in the cortex of the brain

Compare blood flow patterns when resting vs. exercising How does the distribution of blood change?

At rest, most blood goes to intestines, liver, brain, and some to muscles. AT heavy excercise, we see a huge increase in blood to the muscles, and decrease in all other areas. Heart stays the same in both situations

Atherosclerosis:

Atherosclerosis -- hardening and narrowing of the arteries -- silently and slowly blocks arteries, putting blood flow at risk. It's the usual cause of heart attacks, strokes, and peripheral vascular disease -- what together are called cardiovascular disease. Atherosclerosis begins with damage to the endothelium. It's caused by high blood pressure, smoking, or high cholesterol. That damage leads to the formation of plaque.When bad cholesterol, or LDL, crosses the damaged endothelium, the cholesterol enters the wall of the artery. That causes your white blood cells to stream in to digest the LDL. Over years, cholesterol and cells become plaque in the wall of the artery

Relate HDL and LDL to atherosclerosis

Atherosclorosis causes low HDL and high LDL which is bad

What structures does air pass through when breathing in? When breathing out? Be able to put in order

Breath in: nasal cavitiy, pharynx, larynx, trachea, lungs ( bronchus, bronchiole, alveolar duct, alveolar sac, cappilary

Explain how sudden cardiac arrest and heart attacks differ.

Cardiac arrest has to do with electrical disturbances in your heart while heart attack s are caused by blockages in the arteries

Compare total cardiac output when resting vs. exercising.

Cardiac output at rest= 5 liters per minute Cardiac output at excercise= 25 liters per minute

Describe how atherosclerosis can lead to health problems

Causes a rise in blood pressure and cholesterol, causing blackages in the heart

systole

Contraction of the heart

Describe the changes that take place in the body during breath holding (specifically the variables we consider today) know which go up, which go down and be able to explain, at least in a basic way, why

Diaphragm contraction: no change Pulse rate: increase Systolic blood pressure: increase Blood acidity (pH): decrease Blood CO2: increase Blood O2: decrease Blood glucose: increase Blood lactate: Increase

Myocardial infarction (heart attack)

During a heart attack, the blood supply that normally nourishes the heart with oxygen is cut off and the heart muscle begins to die. There are a few cardiac conditions that can cause heart attacks. One of the most common causes is plaque buildup in the arteries (atherosclerosis) that prevents blood from getting to the heart muscle. Heart attacks can also be caused by blood clots or a torn blood vessel. Less commonly, a heart attack is caused by a blood vessel spasm.

Identify cellular respiration inputs and outputs. How do these relate to the cardiovascular and respiratory systems?

Essentially, sugar (C6H12O6) is burned, or oxidized, down to CO2 and H2O, releasing energy (ATP) in the process. Why do cells need ATP? ALL cellular work -all the activities of life - requires energy, either from ATP or from related molecules. A lot of oxygen is required for this process! The sugar AND the oxygen are delivered to your cells via your bloodstream.

Differentiate between "eustress" and "distress." When is stress good?

Eustress= good stress, can be positive, motivating force, improve quality of life, positive feelings, optimal health and performance DIstress= bad stress, when stress exceeds the optimal level, no longer positive, debilitating, burned out, fatigue, exhausted, performance decline, health erodes

Describe lifestyle changes that could be implemented to improve heart health.

Exercising and healthy eating habits

What is the "fight or flight" response? With which part of the nervous system is this response associated?

Fight or flight response: response to any perceived threat, body undergoes a series of changes—a direct function of sympathetic activation—preparing him to face the threat. His pupils dilate, his heart rate and blood pressure increase, his bladder relaxes, his liver releases glucose, and adrenaline surges into his bloodstream. This constellation of physiological changes, known as the fight or flight response, allows the body access to energy reserves and heightened sensory capacity so that it might fight off a threat or run away to safety. Associated with the Sympathetic nervous system

alarm reaction

First stage of the GAS, during which the body mobilizes its resources to cope with a stressor.

List some of the negative health consequences of chronic stress

For example, stress often contributes to the development of certain psychological disorders, including post-traumatic stress disorder, major depressive disorder, and other serious psychiatric conditions. Additionally, stress is linked to the development and progression of a variety of physical illnesses and diseases

alveoli

Gas exchange occurs only in the alveoli. The alveoli are thin-walled and look like tiny bubbles within the sacs. The alveoli are in direct contact with capillaries of the circulatory system. Such intimate contact ensures that oxygen will diffuse from the alveoli into the blood. In addition, carbon dioxide will diffuse from the blood into the alveoli to be exhaled. The anatomical arrangement of capillaries and alveoli emphasizes the structural and functional relationship of the respiratory and circulatory systems. Estimates for the surface area of alveoli in the lungs vary around 100 m2. This large area is about the area of half a tennis court. This large surface area, combined with the thin-walled nature of the alveolar cells, allows gases to easily diffuse across the cells.

Where exactly does gas exchange take place? What gases are being exchanged? Relate this to oxygenated and de-oxygenated blood

Gas exchange takes place in alveoli, which are in direct contact with the cappilaries- diffuses O2 into blood and CO2 out of blood to be exhaled(oxygenated going into cappilaries, deoxygenated going out of cappilaries)

What happens to cardiac output when heart rate goes up?

Heart rate x Stroke volume= cardiac output Cardiac output increases when heart rate increases

what happens to cardiac output When stroke volume goes up?

Heart rate x Stroke volume= cardiac output Cardiac output increases when stroke volume increases

Differentiate between heart rate and stroke volume.

Heart rate= beats per minute Stroke volume= liters per beat

Explain how short and long term effects of stress differ.

However, extended release of cortisol—as would happen with prolonged or chronic stress—often comes at a high price. High levels of cortisol have been shown to produce a number of harmful effects. For example, increases in cortisol can significantly weaken our immune system. In summary, a stressful event causes a variety of physiological reactions that activate the adrenal glands, which in turn release epinephrine, norepinephrine, and cortisol. These hormones affect a number of bodily processes in ways that prepare the stressed person to take direct action, but also in ways that may heighten the potential for illness. When stress is extreme or chronic, it can have profoundly negative consequences.

Why could high blood pressure (hypertension) be a problem?

Hypertension, or high blood pressure, is when your blood travels through blood vessels with more force than is considered healthy. When blood pressure is high, it can damage artery and blood vessel walls over time. This leads to dangerous complications and even death if left untreated.

What bodily functions change when the parasympathetic division is activated? Think about your daily routine. Which division is most active when you are running to class? Dozing in class?

Once the threat has been resolved, the parasympathetic nervous system takes over and returns bodily functions to a relaxed state. Our hunter's heart rate and blood pressure return to normal, his pupils constrict, he regains control of his bladder, and the liver begins to store glucose in the form of glycogen for future use. These processes are associated with activation of the parasympathetic nervous system. running= sympathetic dozing=parasympathetic

Describe how cellular respiration relates to breathing. What are the reactants and the products?

Oxygen (from breathing ) + glucose---> Carbon dioxide (exhaled) and H2O (also mostly exhaled) and energy

diastole

Relaxation of the heart

stage of resistance

Second stage of the GAS, during which the body adapts to and uses resources to cope with a stressor. less intense than alarm

General Adaptation Syndrome

Seyle's concept that the body responds to stress with alarm, resistance and exhaustion

Summarize how the body directs blood to where it's needed most (metabolism, pre-capillary sphincters, etc)

Slow metabolism- sphincter constricts, less gas exchange needed, less vasolidating substance produced Fast metabolism: more gas exchange needed, more vasolidating substance produced, sphinctor dialates Medula oblongota regulates heart rate \vagus nerve decreases heart rate Regulated by hormones in blood Metabolism slows down in stressful situations

Sudden cardiac arrest

Sudden cardiac arrest is the sudden, unexpected loss of heart function, breathing and consciousness. Sudden cardiac arrest usually results from an electrical disturbance in your heart that disrupts its pumping action, stopping blood flow to the rest of your body. The immediate cause of sudden cardiac arrest is usually an abnormality in your heart rhythm (arrhythmia), the result of a problem with your heart's electrical system.

Compare/contrast the role of the sympathetic and parasympathetic nervous responses in breathing

Sympathetic: increase breathing, involontary Parasympathetic: decrease/ return to normal

Summarize how the body regulates total cardiac output

The body regulates cardiac output with the rate at which the heart beats and the amount of blood it pumps.

Carotid artery

The carotid arteries are major blood vessels in the neck that supply blood to the brain, neck, and face. There are two carotid arteries, one on the right and one on the left.

Differentiate between the systemic and pulmonary circuits. What is the function of each?

The heart is a complex muscle that consists of two pumps: one that pumps blood through pulmonary circulation to the lungs, and the other that pumps blood through systemic circulation to the rest of the body's tissues (and the heart itself)

Explain what the hepatic portal vein is and how blood entering the liver here is different from blood entering from the hepatic artery

The hepatic artery goes right to the liver and the hepatic portal vein goes from intestines to liver.blood is deoxygenated when it goes into the hepatic portal vein while the blood in the hepatic artery is oxygenated

Describe how the hypothalamus, pituitary gland and adrenal glands work together to respond to stress during a "sympathetic" response.

The hypothalamus in the brain is in charge of the stress response. When a stress response is triggered, it sends signals to two other structures: the pituitary gland, and the adrenal medulla. The Hypothalamic Pituitary-Adrenal (HPA) System The stressor activates the Hypothalamic Pituitary Axis The hypothalamus stimulates the pituitary gland The pituitary gland secretes adrenocorticotropic hormone (ACTH) ACTH stimulates the adrenal glands to produce the hormone corticosteroid Cortisol enables the body to maintain steady supplies of blood sugar Adequate and steady blood sugar levels help person to cope with prolonged stressor, and helps the body to return to normal The adrenal cortex releases stress hormones called cortisol. This have a number of functions including releasing stored glucose from the liver (for energy) and controlling swelling after injury, boost of energy when first encounter with stressor, decrease pain. The immune system is suppressed while this happens., long term=wears down immune system=illness, disease, death

Define stress (focus on response based, physiological definitions)

The process in which an individual perceives and responds to events that he/ she appraises as overwhelming or threatening to their well being.

Differentiate between sympathetic and parasympathetic responses of the autonomic nervous system

The sympathetic nervous system is activated when we are faced with stressful or high-arousal situations. The sympathetic nervous system is involved in preparing the body for stress-related activities; the parasympathetic nervous system is associated with returning the body to routine, day-to-day operations. (see above at fight or flight for sympathetic responses)Once the threat has been resolved, the parasympathetic nervous system takes over and returns bodily functions to a relaxed state. Our hunter's heart rate and blood pressure return to normal, his pupils constrict, he regains control of his bladder, and the liver begins to store glucose in the form of glycogen for future use. These processes are associated with activation of the parasympathetic nervous system.

Arrhythmia:

The term "arrhythmia" refers to any change from the normal sequence of electrical impulses. The electrical impulses may happen too fast, too slowly, or erratically - causing the heart to beat too fast, too slowly, or erratically Causes Normally, the heart's most rapidly firing cells are in the sinus (or sinoatrial or SA) node, making that area a natural pacemaker. Under some conditions almost all heart tissue can start an impulse of the type that can generate a heartbeat. Cells in the heart's conduction system can fire automatically and start electrical activity. This activity can interrupt the normal order of the heart's pumping activity. Secondary pacemakers elsewhere in the heart provide a "back-up" rhythm when the sinus node doesn't work properly or when impulses are blocked somewhere in the conduction system. An arrhythmia occurs when: The heart's natural pacemaker develops an abnormal rate or rhythm. The normal conduction pathway is interrupted. Another part of the heart takes over as pacemaker.

stage of exhaustion

Third stage of the GAS, during which the body depletes its resources in responding to an ongoing stressor. illness, disease, death

Describe a scenario in which stress has a positive effect on performance

You are stressed about passing a class so you study and get a good grade, stress about being unhealthy so you work out, stress about a soccer game so you practice and prep, stress about getting fired or not getting pay raise so you do a good job at work

Explain how the cardiovascular and respiratory systems work together to provide the energy that the body needs.

You get energy through the respitory system (breathing) and then this is exchanged in the cardiovascular system to the body through blood flow (given to blood through aveoli sacs)

hypothalamic-pituitary-adrenal (HPA) axis

a major neuroendocrine pathway relevant to the stress response involving the hypothalamus, pituitary gland, and the adrenal cortex

Pulmonary vein

a vein carrying oxygenated blood from the lungs to the left atrium of the heart.

-Alveolar ducts

are attached to the end of each respiratory bronchiole. At the end of each duct are alveolar sacs, each containing 20 to 30 alveoli

Veins

are blood vessels that bring blood high in carbon dioxide back to the heart. Veins are not as thick-walled as arteries, since pressure is lower, and they have valves along their length that prevent backflow of blood away from the heart. The major veins drain blood from the same organs and limbs that the major arteries supply.

efferent

carry or move away from a central structure, motor

Capillary beds

contain a large number, 10's to 100's of capillaries that branch among the cells of the body. Capillaries are narrow-diameter tubes that can fit single red blood cells and are the0 sites for the exchange of nutrients, waste, and oxygen with tissues at the cellular level. Fluid also leaks from the blood into the interstitial space from the capillaries. The capillaries converge again into venules that connect to minor veins that finally connect to major veins.

Atria

each of the two upper cavities of the heart from which blood is passed to the ventricles. The right atrium receives deoxygenated blood from the veins of the body; the left atrium receives oxygenated blood from the pulmonary vein.

afferent

in neurons, another name for sensory, carry toward CNS

adrenaline (epinephrine)

secreted by the adrenal medulla; increases heart rate and blood pressure

Baroreceptors:

senses differences in pressure of blood, located in the aorta and carotid artery

Chemo-receptors:

senses differences of chemicals in blood, in aorta and carotid artery

Arterioles

smallest arteries, diverge into cappilary beds

cortisol

stress hormone released by the adrenal cortex

How do sympathetic vs. parasympathetic nerves affect the heart?

sympathetic= increase heart rate, increase cardiac output Parasympathetic= decrease heart rate, decrease cardiac output

Arteries

take blood away from the heart. The main artery of the systemic circulation is the aorta; it branches into major arteries that take blood to different limbs and organs. The aorta and arteries near the heart have heavy but elastic walls that respond to and smooth out the pressure differences caused by the beating heart. Arteries farther away from the heart have more muscle tissue in their walls that can constrict to affect flow rates of blood. The major arteries diverge into minor arteries, and then smaller vessels called arterioles, to reach more deeply into the muscles and organs of the body.

Pulmonary artery

the artery carrying blood from the right ventricle of the heart to the lungs for oxygenation.

primary appraisal

the first step in assessing stress, which involves estimating the severity of a stressor and classifying it as either a threat or a challenge

Aorta

the main artery of the body, supplying oxygenated blood to the circulatory system. In humans it passes over the heart from the left ventricle and runs down in front of the backbone.

autonomic nervous system

the part of the peripheral nervous system that controls the glands and the muscles of the internal organs (such as the heart). Its sympathetic division arouses; its parasympathetic division calms.

secondary appraisal

the second step in assessing a threat, which involves estimating the resources available to the person for coping with the stressor

Predict changes in HDL and LDL with age and lifestyle

young= hdl is low, ldl is high (normal) but if your lifestyle is bad then... old= high ldl and low hdl= bad, if you keep going then atherosclerosis could cause you to have a heart attack. If you become healthier in living, you can get your hdl and ldl back to normal