Midterm 2

Question 1

Peripheral Nervous System Parts

Answer 1

Sensory Division: somatic sense & special senses
Motor Division: somatic NS (skeletal muscles) & autonomic NS [sympathetic NS f&f, parasympathetic NS r&d (smooth muscle, cardiac muscle + glands), enteric NS (smooth muscle + glands in GI tract)]

Question 2

D: photoreceptor

Answer 2

detect light that strikes the retina of the eye

Question 3

D: mechanoreceptor

Answer 3

mechanical stimuli such as deformation, stretching, bending of cells

Question 4

D: thermoreceptor

Answer 4

detect changes in temp

Question 5

D: nociceptor

Answer 5

respond to painful stimuli resulting from physical or chemical damage to the tissue

Question 6

D: osmoreceptors:

Answer 6

detect osmotic pressure of body fluids

Question 7

D: chemoreceptor

Answer 7

detect chemicals in the mouth, nose and body fluids

Question 8

D: pacinian corpuscles

Answer 8

oval-shaped pressure-receptor located in the dermis of the subcutaneous tissue consisting of concentric layers of connective tissue wrapped around the dendrites of the sensory neuron

Question 9

ear parts

Answer 9

External: auricle, external auditory cannal, eardrum
Middle: auditory tube, auditory ossicles, oval window
Internal: bony labyrinth, membranous labyrinth (contains the spiral organ)

Question 10

Olfactory receptor

Answer 10

-respond to hundreds of different odorant molecules by producing an electrical signal that triggers one or more nerve impulses
-we can recognize about 10,000 different odors from the activation of the different combinations of olfactory receptors
adaption (decreasing sensitivity to odors occurs rapidly. Olfactory receptors adapt by 50% in the first or second after stimulation

Question 11

Gustatory cells

Answer 11

• located in the taste buds. substances dissolve in saliva. five primary tastes are: salty, sweet, sour, bitter, and umami
• they trigger impulses in these cranial nerves: facial, glossopharyngeal, and vagus.
• impulses for taste conduct to the medulla oblangata, limbic system, hypothalamus, thalamus, and the primary gustatory ares in the parietal lobe of the cerebral cortex

Question 12

Eye parts, rods and cones

Answer 12

Three layers of the eye: Fibrous tunic (schlera and cornea), vascular tunic (choroid, ciliary body, and iris), and retina (consists of a neural layer [photoreceptor layer, bipolar cell layer, and ganglion cell layer] and a pigmented layer. The anterior cavity contains aqueous humor; the vitreous chamber contains the vitreous body.
-stimulation of the rods and cones then activates bipolar cells, which in turn activate the ganglion cells. Rods: we have more of them, very sensitive, see black and white
Cones: fine detail and colour

Question 13

Accessory structures of the eye

Answer 13

eyebrows, eyelids, eyelashes, the lacrimal apparatus (which produces and drains tears), and extrinsic eye muscles (which moves the eyes).

Question 14

Adaptation

Answer 14

• a decrease in the strength of a sensation during a prolonged stimulus
• caused by a decrease in the responsiveness to sensory receptors
• as a result of adaptation, the perception of a sensation may fade of disappear even though the stimulation persists.
• receptors associated with pressure, touch, and smell are rapid adapting
• receptors associated with pain, body position, and chemical composition of the blood are slow adapting

Question 15

Hormones: Insulin and Glucagon (8steps)

Answer 15

• main action of glucagon is to increase blood glucose level when it falls below normal
• insulin helps glucose move into cells, especially in muscle fibers, which lowers blood glucose level when it is too high.
• the level of blood glucose controls secretion of both glucagon and insulin via negative feedback
  1. low blood glucose stimulates the alpha cells to secrete
  2. (GLUCAGON) acts on liver cells to 1. convert glycogen into glucose and 2 form glucose from lactic acid and certain amino acids
  3. glucose released by liver cells raises blood glucose level to normal
  4. if blood glucose continues to rise, hyperglycemia inhibits release of glucagon
  5. high blood glucose stimulates beta cells to screte
  6. (INSULIN) acts on various body cells to 1. accelerate facilitated diffusion of glucose into cells, 2 speed conversion of glucose into glycogen, 3 increase uptake of amino acids and increase protein synthesis
  7. blood glucose level falls
  8. if blood glucose continues to fall, hypoglycema inhibits release of insulin

Question 16

Hormones: Epinephrine and nor-epinephrine

Answer 16

• raise blood pressure
• the adrenal medullae secrete them, when under stress (or during exercise)
• about 80% epinephrine and 20% nor-epinephrine
• fight or flight response. By increasing heart rate and force of contraction, they increase the pumping output of the heart, which increases blood pressure. They also increase blood flow to the heart, liver, skeletal muscles, and adipose tissue; dilate airways to the lungs; increase blood levels of glucose and fatty acids; and help the body resist acute stress

Question 17

Hormones: Thyroid

Answer 17

• regulate oxygen use and basal metabolic rate, cellular metabolism, and growth and development
• Thyroid-stimulating hormone (TSH) stimulates the synthesis and secretion of thyroid hormones by the thyroid gland

Question 18

Hormones: Calcitonin

Answer 18

• lowers the blood level of calcium; it’s secretion is controlled by the level of calcium in the blood
• produced by the parafollicular cells of the thyroid gland
• can decrease the level of calcium in the blood by inhibiting the action of osteoclasts, the cells that break down bone.
• the secretion of calcitonin is controlled by negative feedback system
• miacalcin, a calcitonin extract from salmon, is an effective treatment for osteoperosis

Question 19

Hormone: growth hormone

Answer 19

• decreases with advancing age
• is the most abundant anterior pituitary hormone
• main function is to promote synthesis and secretion of small protein hormones called insulinlike growth factors
• also enhance breakdown of triglycerides ], which releases glucose into the blood

Question 20

Hormone: antidiuretic hormone

Answer 20

• made in the hypothalamus and released in the posterior pituitary
• ADH secretion is controlled by the osmotic pressure of the blood and blood volume
• constantly regulates and balances the amount of water in the blood
• most important role is to conserve the fluid volume of your body by reducing the amount of water passed out in the urine

Question 21

Receptor types

Answer 21

sensory receptor: a stimulus, or change in the environment, capable of activating certain sensory neurons
Olfactory receptor: a bipolar neuron w an exposed dendrite and axon. on the dendrite is cilia, which are sites that responses can be generated. they respond to the chemical stimulation of an odorant molecule by producing an olfactory response
gustatory receptor: 50 in each taste bud.

Question 22

Endocrine glands

Answer 22

• secrete hormones into interstitial fluid and then diffuse into the blood
• include the pituitary, thyroid, parathyroid, adrenal, and pineal glands, thymus, pancreas, ovaries, testes, kidneys, stomach, liver, small intestine, skin, heart, adipose tissue, and placenta

Question 23

Blood functions (3)

Answer 23

Transportation: transports oxygen, carbon dioxide, nutrients, wastes, and hormones.
Regulation: regulates pH, body temp, and water contents
Protection: prevents blood loss through clotting and homeostasis. Phagocytic white blood cells and specialized proteins fight against microbes and toxins

Question 24

Blood components

Answer 24

Red blood cells, white blood cells [granular leukocytes like neutrophils, basophils and Agranular leukocytes like T & B lymphocytes and Monocytes], and platelets
RBC: biconcave disks wihtout nuclei that contain hemoglobin, live about 120 days, males have about 5.4 million/mL, females have about 4.8 million/mL, formation happens in red bone marrow
WBC: are nucleated cells, combats inflammation and infection, live for only a few days, 5000-10000 WBC/mL
Platelets: disc-shaped cell fragments without nuclei, 150000-400000/mL, lifespan of 5-9 days

Question 25

Blood Types

Answer 25

- ABO system: antigens determine blood type - Rh system: Rh antigens = Rh+, no Rh = Rh-. - Neither Rh+ or RH- persons have anti-Rh antibodies in plasma. But exposure can cause the Rh- person to develop Rh antibodies. - a disorder due to Rh incompatibility between mother and fetus is called hemolytic disease of the newborn

Question 26

Blood characteristics

Answer 26

- thickness greater than that of water - temp of 38 d - pH range between 7.35 and 7.45 - constitutes 8% of body weight in adult - consists of 55% plasma and 45% formed elements - is liquid connective tissue that consists of cells surrounded by an extracellular matrix - hemopoisis, the formation of blood cells from pluripotent stem cells, occurs in red bone marrow

Question 27

Hemostasis

Answer 27

the stoppage of bleeding, involves muscular spasm (the smooth muscle of a blood vessel wall contracts), platelet plug formation (aggregation of platelets to stop bleeding), and blood clotting (network of insoluble protein fibres in which formed elements of blood are trapped).

Question 28

Hemoatopoiesis

Answer 28

the process by which the formed elements of blood develop - before birth: occurs in the yolk sac of an embryo - 3 months before birth, occurs in red bone marrow

Question 29

Liquid connective tissue

Answer 29

blood is a liquid connective tissue that consists of cells surrounded by an extracellular matrix

Question 30

Heart components

Answer 30

-between the lungs, left of the midline -held in position by pericardium -chambers include two upper atria and two lower ventricles -apex is the inferior pointed end of the heart, base is the superior portion, the percardium is composed of a parietal layer and a visceral layer -blood flows to the heart from the superior and inferior vena cavae.. throught the pulmonary arteries to the lungs

Question 31

Heart layers (4)

Answer 31

percardium, epicardium, myocardium, endocardium

Question 32

Heart valves (4)

Answer 32

tricuspid valve, pulmonary valve, mitral valve, and aortic valve

Question 33

Heart conduction system (5)

Answer 33

- consists of specializes cardiac muscle tissue that generates and distributes action potentials components: 1. sinoatrial (SA) node 2. atrioventricular (AV) node 3. atrioventricular (AV) bundle 4. right and left bundle branches 5. purkinje fibers

Question 34

Heart electrocardiogram

Answer 34

- the record of electrical changes during each cardiac cycle - consists of a P wave, QRS complex, and T wave. - used to diagnose abnormal cardiac rhythms and conduction patterns

Question 35

Heart/blood disorders (5)

Answer 35

Myocardial Infection (heart attack): gross necrosis of myocardial tissue due to interrupted blood supply Ischemia: a lack of sufficient blood to a body part due to an obstruction of constriction of a blood vessel Angina Pectoris: a pain in the chest related to reduced coronary circulation due to CAD Coronary artery disease: the heart muscle does not receive and adequate amount of blood because of an interruption in the blood supply Atherosclerosis: the process in which fatty substances are deposited in the walls of the medium sized and large arteries resulting in an empeded blood flow

Question 36

Pulse

Answer 36

- the alternate expansion and elastic recoil of an artery with each heart beat - normal pulse rate is about 75 beats per minute

Question 37

Blood vessel components/characteristics

Answer 37

* Arteries carry blood away from the heart. Their walls consist of three layers. The structure of the middle layer gives arteries their two major properties, elasticity and contractility. * Arterioles are small arteries that deliver blood to capillaries. Through constriction and dilation, arterioles play a key role in regulating blood flow from arteries into capillaries. * Capillaries are microscopic blood vessels through which materials are exchanged between blood and interstitial fluid. Precapillary sphincters regulate blood flow through capillaries. Capillary blood pressure “pushes” fluid out of capillaries into interstitial fluid (filtration). Blood colloid osmotic pressure “pulls” fluid into capillaries from interstitial fluid (reabsorption). * Venules are small vessels that emerge from capillaries and merge to form veins. They drain blood from capillaries into veins. * Veins consist of the same three layers as arteries but have less elastic tissue and smooth muscle. They contain valves that prevent backflow of blood. Weak venous valves can lead to varicose veins. * Venous return, the volume of blood flowing back to the heart through systemic veins, occurs due to the pumping action of the heart, aided by skeletal muscle contractions (the skeletal muscle pump), and breathing (the respiratory pump).

Question 38

Stroke Volume/Cardiac Output

Answer 38

Cardiac output (CO) is the amount of blood ejected by the left ventricle into the aorta each minute: CO = stroke volume X beats per minute. Stroke volume (SV) is the amount of blood ejected by a ventricle during ventricular systole. It is related to stretch on the heart before it contracts, forcefulness of contraction, and the amount of pressure required to eject blood from the ventricles.

Question 39

Gas exchange

Answer 39

- taking in oxygen and blowing off carbon dioxide - the cardiovascular system aids gas exchange by transporting blood containing the gases between the lungs and tissue cells

Question 40

Lymphatic system organs

Answer 40

* Primary Lymphatic Organ: Primary are where stem cells divide and develop into mature B calls and T cells- red bone marrow and thymus. Thymus: two lobed organ located posterior to the sternum, medial to the lungs, and superior to the heart. T-cells mature in the Thymus. Red bone marrow: site of T-cell and B-cell formation. Only B-cells mature in red bone marrow * Secondary Lymphatic Organ: The secondary lymphatic organs and tissues are the sites where most immune responses occur. They include lymph nodes, the spleen, and lymphatic nodules. Lymph nodes contain B cells that develop into plasma cells, T cells, dendritic cells, and macrophages. Lymph enters nodes through afferent lymphatic vessels and exits through efferent lymphatic vessels. The spleen is the single largest mass of lymphatic tissue in the body. It is where B cells divide into plasma cells and macrophages phagocytize worn-out red blood cells and platelets. Lymphatic nodules are oval-shaped concentrations of lymphatic tissue that are not surrounded by a capsule. They are scattered throughout the mucosa of the gastrointestinal, respiratory, urinary, and reproductive tracts.

Question 41

Lymphatic system components

Answer 41

* The body system responsible for adaptive immunity (and some aspects of innate immunity) is the lymphatic system. Consists of lymph, lymphatic vessels, structures and organs that contain lymphatic tissue, and red bone marrow. * Components of blood plasma filter through blood capillary walls to form interstitial fluid, the fluid that bathes the cells of body tissues. After interstitial fluid passes into lymphatic vessels, it is called lymph.

Question 42

Lymphatic system functions

Answer 42

* Drains excess interstitial fluid. * The lymphatic system drains tissue spaces of excess fluid and returns proteins that have escaped from blood to the cardiovascular system. * Transports dietary lipids and lipid-soluble vitamins to the blood. * It also transports lipids and lipid-soluble vitamins from the gastrointestinal tract to the blood, and protects the body against invasion. * Carries out immune responses.

Question 43

Lymphatic system flow

Answer 43

Lymphatic vessels begin as lymphatic capillaries in tissue spaces between cells. The lymphatic capillaries merge to form larger lymphatic vessels, which ultimately drain into the thoracic duct or right lymphatic duct. Located at intervals along lymphatic vessels are lymph nodes, masses of B cells and T cells surrounded by a capsule. The passage of lymph is from interstitial fluid, to lymphatic capillaries, to lymphatic vessels and lymph nodes, to the thoracic duct or right lymphatic duct, to the junction of the internal jugular and subclavian veins. Lymph flows due to the “milking action” of skeletal muscle contractions and pressure changes that occur during inhalation. Valves in the lymphatic vessels prevent backflow of lymph. Primary lymphatic organs are the sites where stem cells divide and develop into mature B cells and T cells. They include the red bone marrow (in flat bones and the ends of the long bones of adults) and the thymus. Stem cells in red bone marrow give rise to mature B cells and to immature T cells that migrate to the thymus, where they mature into functional T cells.