Anatomy and Physiology Exam #1

5 effects on the body due to sympathetic activation

1. increased heart rate

2. dilation of pupils

3. increased blood pressure

4. sweat production

5. decreased gastrointestinal movement

5 targets of the parasympathetic division

1. heart

2. digestive system

3. respiratory system

4. eyes

5. urinary system

synapse

a small gap at the end of a neuron that allows the signals to pass from one neuron to the next

autonomic ganglia

clusters of nerve cell bodies

postganglionic neuron

a nerve cell that carries signals away from an autonomic ganglion to an effector organ

craniosacral

referring to the two main divisions of the parasympathetic nervous system

thoracolumbar

referring to the two main divisions of the sympathetic nervous system

varicosities

swollen, bead-like structures along the length of certain autonomic nerve fibers

adrenal medulla

innermost part of the adrenal glands, which are small triangular-shaped glands located on top of each kidney

visceral motor neuron

use neurotransmitters to transmit signals

neuron that contributes to both the sympathetic and parasympathetic functions

neurotransmitter (+example)

a chemical messenger that transmits signals across synapses

example: acetylcholine

dual innervation by the autonomic nervous system (+example)

most visceral organs receive input from both the sympathetic and parasympathetic divisions

example: the heart is influenced by both the sympathetic and parasympathetic nervous systems

collateral ganglia (+example)

clusters of nerve cell bodies located at a distance from the spinal cord, they are involved in regulating functions of abdominal organs

example: celiac ganglia

sympathomimetic drug (+example)

a substance that mimic or enhances the effects of the sympathetic nervous system

example: epinephrine (adrenaline)

explain why epinephrine and norepinephrine can be considered both neurotransmitters and hormones

they help signals jump from one messenger to another at synapses but they also reach different parts of the body and prepare it for action

explain how the vagus nerve controls most of the output of the parasympathetic nervous system

it serves as the main conduit for parasympathetic signals that originate in the brain and influence various organs throughout the body

explain how fight or flight allows us to deal with a crisis

the fight or flight response is a set of physiological changes that prepares the body to cope with a crisis by optimizing physical and mental capabilities

somatic versus autonomic divisions of the nervous system

the somatic nervous system control voluntary movements and skeletal muscles

the autonomic system regulated involuntary functions of internal organs , maintaining the body’s internal environment

adrenergic versus cholinergic receptors

adrenergic receptors respond to norepinephrine and epinephrine, mediating sympathetic responses

cholinergic receptors respond to acetylcholine, mediating parasympathetic responses

length of preganglionic neuron of sympathetic versus parasympathetic division

preganglionic neurons are shorter in the sympathetic division and longer in the parasympathetic division

nicotinic versus muscarinic receptor

nicotinic receptors mediate rapid responses

muscarinic receptors meidate slower and more prolonged responses

alpha versus beta receptors

alpha receptors cause vasoconstriction

beta receptors have diverse effects on the heart, lungs, and other organs, contributing to the body’s response to stress and danger

2 hormones that regulate Ca2+ levels

1. parathyroid hormone (PTH)

2. calcitonin

2 effects of thyroid hormones on the body

1. metabolic rate regulation

2. energy homeostasis and nutrient utilization

2 hormones secreted from the pancreas

1. insulin

2. glucagon

4 hormones secreted from the adrenal gland

1. cortisol

2. aldosterone

3. epinephrine and norepinephrine

4. androgens

2 hormones that are regulated by CRH

1. adrenocorticotropic hormone (ACTH)

2. thyrotropin-releasing hormone (TRH)

2 targets of growth hormone (GH)

1. muscles and bones

2. immune system

second messenger

a substance whose release within a cell is promoted by a hormone and brings about a response to the cell

hypophyseal portal system

a specialized vascular arrangement that connects the hypothalamus and the anterior pituitary gland

facilitates the communication of hormones

upregulation

the process by which a cell increases its response to a substance or signal from outside the cell to carry out a specific function

antidiuretic (ADH)

a chemical produced in the brain that causes the kidneys to release less water, decreasing the amount of urine produced

calorigenic effect

the measure of increased metabolic rate and increase in the consumption of oxygen

prolactin (PRL)

a hormone that’s responsible for lactation

oxytocin

a hormone released by the pituitary gland that causes increases contraction of the uterus and stimulates the ejection of milk of the breasts

releasing hormone (+example)

a type of hormone that stimulates the release of another hormone

example: thyroid-releasing hormone (TRH)

inhibiting hormone (+example)

a type of hormone that suppresses or inhibits the release of another hormone from an endocrine gland

example: growth hormone-inhibiting hormone (GHIH)

steroid hormone (+example)

hormones derived from cholesterol and characterized by their lipid-soluble nature

example: cortisol

gonadotropins (+example)

a group of hormones that stimulate the gonads to produce sex hormones and gametes

example: follicle-stimulating hormone (FSH)

synergistic effect (+example)

situation in which the combined action of two or more factors, results in an effect greater than the individual effects

Example: antibiotic and beta-inhibitors

explain how the kidneys are involved in the regulation of sodium and potassium levels in the blood

the kidneys manage the levels of sodium and potassium by filtering, reabsorbing, and then pushes the extra into the urine

explain how the pancreas regulates blood glucose levels

the pancreas produces insulin and glucagon which manage blood sugar levels and maintains balanced levels

explain how the hypothalamus controls the endocrine system

the hypothalamus makes sure everything in the body is doing their job, it send messages to other glands telling them what to do and how to adjust

hormonal versus humoral stimuli (+example)

hormonal: occurs with the release of hormones triggered by the presence of other hormones

example: T3 and T4 is stimulated by the release of TSH

humoral: change in extracellular fluid

example: insulin is stimulated by high blood glucose levels

endocrine versus neuronal stimuli (+example)

endocrine: involves the release of hormones in response to changes in the internal environment or signals from other hormones

example: thyroid hormone regulation

neuronal: involves the release of hormones in response to neural signals

example: fight or flight response

hormones that bind to surface cell receptors versus intracellular receptors

hormones that bind to surface: typically water-soluble and cannot pass through the cell membrane

example: peptide hormones (insulin, GH, and glucagon)

intracellular: typically lipid-soluble and can pass through the cell membrane

example: steroid hormones (testosterone, estrogen, and cortisol)

peptide versus lipid derived hormone (+example)

peptide: made up of amino acids and form short chains of peptide, are water-soluble

example: insulin, GH, oxytocin

lipid-derived: derived from lipids and include steroids, lipid-soluble

example: testosterone, estrogen, cortisol

functions of the blood in the cardiovascular system

• transports oxygen and nutrients

• distribution of hormones

• maintains body temperature

• fluid balance

three phases of hemostasis

1. vasoconstriction

   • helps reduce blood flow to injured area

2. platelet plug

   • stop bleeding by forming a temporary plug

3. coagulation

   • sealing the injured area to prevent further bleeding

components of whole blood

• plasma

  • liquid component

  • makes up about 55%

• formed elements

  • RBCs, WBCs, platelets

• buffy coat

  • WBCs and platelets

  • immune response and blood clotting

• hematocrit

  • percentage of blood volume occupied by RBCs

hematocrit

ratio of the volume of RBCs to the total volume of blood

erythrocyte

a RBC that contains hemoglobin and transports oxygen and carbon dioxide to and from tissues

hemostasis

the stopping of a flow of blood

thrombin

an enzyme in blood plasma which causes the clotting of blood by converting fibrinogen to fibrin

hematopoiesis

blood cell production

colony stimulating factor (CSF)

a substance secreted by bone marrow which promotes the growth of stem cells into colonies of specific blood cells

hemotopoietic stem cell

an immature cell that can develop into all types of blood cells, (RBCs, WBCs, and platelets)

thrombocytopenia

deficiency of platelets in blood, causing bleeding into the tissues (bruising)

leukopenia

a reduction in the number of white blood cells in the blood

leukemia

a disease in which the bone marrow and other blood-forming organs produce increased numbers of immature or abnormal leukocytes

major plasma proteins (+example)

proteins that are found in the liquid component of blood called plasma, they maintain osmotic pressure, transport substances, and contribute to the immune response

example: albumins, globulins, and fibrinogen

agglutinin (+example)

an antibody that causes clumping to agglutination of cells, immune system’s response to foreign substances

example: anti-A agglutinin, anti-B agglutinin

agglutinogen (+example)

an antigen that can induce the clumping or agglutination of cells, agglutinogens on the surface of red blood cells can determine an individuals blood type

example: A and B antigens

anticoagulant (+example)

a substance that prevents or inhibits blood clotting

example: heparin

granulocyte (+example)

a type of WBC characterized by the presence of granules in their cytoplasm

example: neutrophils, basophils

explain how the structure of red blood cells provide for their function

the biconcave shape maximizes the surface area for flexibility

lack of nucleus provide more space for hemoglobin, maximizing the cell’s oxygen carrying capacity

explain how EPO regulated RBC production

EPO is produced and released by the kidneys, especially in response to low oxygen levels in the blood

EPO travels in the blood stream to the bone marrow, where RBCs are produced

explain how red blood cell components are degraded

the components of RBCs are broken down and recycled in a process known as RBC catabolism

explain how platelets aid in hemostasis

platelets form a temporary plug at the site of injury and they contribute to the formation of a stable blood clot

explain how white blood cells contribute to immunity

they play a central role in defending the body against infections, pathogens and foreign substances

deoxyhemoglobin versus oxyhemoglobin

what determines these states

deoxyhemoglobin: hemoglobin without oxygen, found in tissues where oxygen has been given to cells for their needs

oxyhemoglobin: hemoglobin with oxygen, predominant in the lungs where hemoglobin picks up oxygen

neutrophil versus basophil (+example)

neutrophils: most abundance type of WBC, often the first responders to infections

example: a cut becomes infected, neutrophils migrate to the site of infection

basophils: involved in the inflammatory and allergic responses, release histamine

example: in an allergic reaction, basophils release histamine

parietal pericardium

the outer layer of the pericardium which is a sac of fibrous tissue that surrounds the heart

pericarditis

inflammation of the pericardium

myocardial infarction

heart attack

decreased or complete cessation of blood flow to a portion of the myocardium

coronary ischemia

heart problems caused by narrowed heart (coronary) arteries that supply blood to the heart msucle

isovolumetric contraction

the phase of systole when both valves are closed

stroke volume

the volume of blood pumped out of the left ventricle of the heart during systolic cardiac contraction

end diastolic volume

the amount of blood that is in the ventricles before the heart contracts

tachycardia

an increased heart rate

AV valves (+example)

heart valves located between the atria and the ventricles of the heart

example: tricuspid valve, mitral valve

semilunar valves (+example)

heart valves located between the ventricles of the heart and the major arteries that carry blood away from the heart

example: aortic valve, pulmonary valve

explain how blood flows through the pulmonary circuit, indicating the major chambers, vessels, and valves involved

1. right atrium

2. tricuspid valve

3. right ventricle

4. pulmonary valve

5. pulmonary artery

6. lungs

7. pulmonary veins

8. left atrium

9. mitral valve

10. left ventricle

11. aortic valve

12. aorta

13. rest of the body

explain the functions of the four valves of the heart

tricuspid: prevents back flow of blood from the right ventricle to the right atrium during systole

mitral valve: prevents back flow of blood from the left ventricle to the left atrium

pulmonary valve: prevents back flow of blood from the pulmonary artery to the right ventricle during diastole

aortic valve: prevents back flow from the aorta to the left ventricle during diastole

explain why the SA node is considered the natural pacemaker of the heart

because it posses intrinsic electrical properties that enable it to generate rhythmic and regular electrical impulses, initiating the heartbeat

the 3 layers of the heart wall

1. epicardium

2. myocardium

3. endocardium

the major vessels involved in the systemic circuit (connected directly to the heart)

1. aorta

2. systemic arteries

3. arterioles

4. capillaries

5. systemic veins

6. superior and inferior vena cava

components of the conducting system

1. sinoatrial node (SA node): natural pacemaker of the heart

2. atrioventricular node (AV node): receives electrical impulses from the SA node and serves as a delay mechanism allowing the atria to fully contract

3. atrioventricular bundle: rapidly conducts the impulses from the AV node to the ventricles

4. bundle of branches: divides into smaller branches that conduct the impulses to the purkinje fibers

5. purkinje fibers: conduct electrical impulses to the myocardial cells of the ventricles, leading to their contraction

right versus left ventricle

right: receives deoxygenated blood from right atrium and pumps it to the pulmonary artery, thinner wall, tricuspid valve

left: receives oxygenated blood from the left atrium and pumps it into the aorta, thicker wall, mitral valve

systole versus diastole

systole: phase of the cardiac cycle when the heart chambers contract, pushing blood out of the chambers

diastole: phase of the cardiac cycle when the heart chambers relax and fill with blood

arteries versus veins

arteries: carry oxygenated blood away from the heart and to the tissues and organs throughout the body

veins: carry deoxygenated blood from the tissues back to the heart

P wave

depolarization of the atria

QRS complex

depolarization of ventricles

ventricles begin contracting shortly after R wave

T wave

repolarization of ventricles

P-R interval

from start of atrial depolarization, to start of QRS complex

Q-T interval

time required for ventricles to undergo a single cycle of depolarization

pacemaker cells

cardiac muscle tissue contracts without neural or hormonal stimulation

conducting cells

initiate and distribute electrical impulses that stimulate contraction

ectopic pacemaker

• abnormal cells generate high rate of action potentials

• bypass conducting system

• disrupts timing of ventricular contractions