Quiz 3 (Modules 11-15) Flashcards
Somatic senses
Include tactile sensations, thermal sensations, pain sensations, and proprioceptive sensations
Visceral senses
Provide information about conditions within internal organs Eg. pressure, stretch, chemicals, nausea, hunger, and temperature
Special senses
Include the sensory modalities of smell, taste, vision, hearing, and equilibrium
Nociceptors
Respond to painful stimuli resulting from physical or chemical damage to tissue
Osmoreceptors
Detect the osmotic pressure of body fluids
Pressure
A sustained sensation that is felt over a larger area than touch Occurs with deformation of deeper tissues Receptors for pressure sensation include Meissner corpuscles, Merkel discs, and Pacinian corpuscles
Vibration
Sensations that result from rapidly repetitive sensory signals from tactile receptors Receptors for vibration sensations are Meissner corpuscles and Pacinian corpuscles
Organ of smell
Olfactory epithelium
Conjunctiva
Thin, mucus-secreting epithelial membrane that lines the interior surface of each eyelid and the exposed anterior surface of the eyeball 2 layers: Palpebral conjunctiva, and bulbar conjunctiva
Palpebra
Eyelid Protects the eyeball from drying out (dessication)
Palpebral conjunctiva
Thicker of the 2 layers of conjunctiva Adheres to the eyelid
Bulbar conjunctiva
Transparent Covers the surface of the eyeball (extremely thin at cornea)
3 pairs of cranial nerves that control the extrinsic eye muscles
Oculomotor nerves (III) Abducens nerves (VI) Trochlear nerves (IV)
Fibrous layer of the eyeball
Outermost layer Consists of the sclera and cornea
Choroid
Highly vascular, pigmented layer located between the sclera and the retina in the posterior portion of the eye Brown pigment absorbs excess light rays that might interfere with vision
Ciliary body
Ciliary processes secrete aqueous humor Ciliary muscles change the shape of the lens
Rods
Function in dim light Do not detect fine detail or colour Detect motion
Cones
Function in bright light Detect fine detail and colour
Canals of Schlemm
Where aqueous humor drains
Myopia
Nearsightedness (can focus on close, but not far objects) Light rays focus in front of the retina Usually caused by an eyeball that is too long
Hyperopia
Farsightedness (can focus on far, but not close objects)
Light rays focus behind the retina
Usually caused by an eyeball that is too short
Glaucoma
Caused by intraocular pressure when the drainage of aqueous humor has been blocked
3 bones in the middle ear
Malleus Incus Stapes
Semicircular canals of the ear
Three oval-shaped canals that contain receptors that detect motion Concerned with equilibrium (balance)
Hormone
A chemical messenger that is released in one part of the body but regulates the activity of cells in other parts of the body
Down-regulation
If a hormone is present in excess, the number of target-cell receptors may decrease
Makes a target cell less sensitive to a hormone
Up-regulation
When a hormone is deficient, the number of target-cell receptors may increase
Makes a target cell more sensitive to a hormone
Circulating hormones
Pass from the secretory cells that make them into interstitial fluid and then into the blood
Local hormones
Act locally on neighboring cells or on the same cell that secreted them without first entering the bloodstream
Paracrines
Local hormones that act on neighboring cells
Autocrines
Local hormones that act on the same cell that secreted them
Amino-based hormones
Consist of proteins or protein derivatives
Most hormones in the body
React with receptors on the surface of the cell, and reactions are rapid
Steroid hormones
Synthesized from cholesterol
React with receptor sites inside a cell and reactions are slow
Sex hormones and hormones from the adrenal cortex
Follicle-stimulating hormone (FSH)
Stimulates production of sperm in the male
Stimulates maturation of ova and production of estrogen by the ovaries
Secreted by the anterior pituitary
Luteinizing hormone (LH)
Stimulates the production of testosterone in the testes
Stimulates the production of estrogen and progesterone by the ovaries; also stimulates ovulation
Secreted by the anterior pituitary
Thyroid-stimulating hormone (TSH)
Secreted by anterior pituitary gland
Stimulates production of thyroid hormones (T3 and T4)
T3 / T4 (Triiodothyronine / thyroxine)
Secreted by the thyroid gland
Regulate energy balance; increase rate of protein synthesis; regulates growth
Calcitonin
Regulates calcium blood levels by inhibiting the release of calcium from bone tissue to blood (decreases blood calcium levels)
Secreted by the thyroid gland
Parathyroid glands
4 small glands embedded in the thyroid gland
Secrete only PTH (parathyroid hormone), which increases blood calcium levels
Mineralocorticoids
Most common is aldosterone
Target cells - kidneys
Regulate water balance in the body
Glucocorticoids
Most common is cortisol
Increase blood sugar levels
Inhibit inflammation and immune response
Islets of Langerhans
Special tissue in the pancreas that produces insulin and glucagon
Insulin
Produced by the beta cells in the islets of Langerhans
Lowers blood glucose by increasing the rate of glucose transported into cells
Glucagon
Produced by the alpha cells in the islets of Langerhans
Increases blood glucose
Stimulates the liver to convert glycogen into glucose and release it into the blood stream
Thymus gland
Site of production of T cells (involved with immunity)
Secretes thymosin, which regulates the development and function of the immune system
Pineal gland
Affects biorhythms (rates of secretion of other hormones)
Secretes melatonin
Cholecalciferol
Produced by epidermal cells in the skin
Stimulates active transport of dietary calcium into the bloodstream
Anastomosis
The union of the branches of two or more arteries (or veins) supplying the same body region Provides alternative routes for blood to reach a tissue or organ
Collateral circulation
The alternative route of blood flow to a body part through an anastomosis
End artery
An artery that does not anastomose
3 types of capillaries
Continuous capillaries Fenestrated capillaries Sinusoids
Portal vein
A vein that transports blood from one capillary network into another
Bulk flow
A passive process in which large numbers of ions, molecules, or particles in a fluid move together in the same direction (high pressure to lower pressure). Important for regulation of the relative volumes of blood and interstitial fluid
Pressure-driven movement of fluid and solutes from blood capillaries into interstitial fluid
Filtration
Pressure-driven movement from interstitial fluid into blood capillaries
Reabsorption
Cardiac output
The volume of blood that circulates through systemic or pulmonary blood vessels each minute (total blood flow) CO = HR x SV (stroke volume)
Blood flow
The volume of blood that flows through any tissue in a given time period (in mL/min)
Systolic BP
The highest pressure attained in arteries during systole
Diastolic BP
The lowest arterial pressure during diastole
Systole
Ventricular contraction
Diastole
Ventricular relaxation
Vascular resistance depends on
Size of lumen Blood viscosity Total blood vessel length
Shock
Failure of the cardiovascular system to deliver enough O2 and nutrients to meet cellular metabolic needs Inadequate blood flow to body tissues
4 different types of shock
Hypovolemic shock - due to decreased blood volume Cardiogenic shock - due to poor heart function Vascular shock - due to inappropriate vasodilation Obstructive shock - due to obstruction of blood flow
Causes of hypovolemic shock
Acute hemorrhage Loss of body fluids through excessive sweating, diarrhea, vomiting, urination Inadequate intake of fluid
Valve between R atrium and R ventricle of the heart
Tricuspid valve
Valve between L atrium and L ventricle of the heart
Mitral valve
Semilunar valves
Pulmonary valve and aortic valve
Normal pacemaker of the heart
Sinoatrial (SA) node
Age related changes affecting the heart include
Thickening of valve flaps Atherosclerosis Decline in cardiac reserve
The lubb heard during a heart beat (S1) is due to
AV valves closing
The dubb heard during a heart beat (S2) is due to
Semilunar valves closing
Angina pectoris
Chest pain caused by inefficient blood delivery to the heart muscle
3 arteries that branch off the top of the aortic arch
Left common carotid artery: Supplies oxygenated blood to the brain Left subclavian artery: Supplies oxygenated blood to the arms Innominate artery: Supplies oxygenated blood to the upper chest
Peyer’s patches
Lymphatic tissue in the small intestine - control the large numbers of bacteria. They prevent bacteria from penetrating the intestinal wall
Buboes
Buboes are infected lymph nodes. Normally, the lymph nodes trap and destroy antigens (e.g., viruses and bacteria). However, the nodes do not always win the battle and the nodes become very swollen
Anaphylaxis
A severe reaction to something that causes the bronchioles in the lungs to constrict – severe anaphylaxis can result in death
Difference between lymph nodes and lymphatic nodules
Lymphatic nodules are not surrounded by a capsule
Plasmin
The enzyme that hydrolyzes fibrin, resulting in the breakdown of blood clots
