Lecture Quiz 5 Flashcards
What are vitamins?
organic compounds needed for growth and good health
not used for energy
What are the functions of vitamins (vague)?
crucial in helping the body use nutrients
often function as coenzymes
What vitamins are synthesized in the body?
D (skin)
K (intestine)
B (intestine)
What are the water soluble vitamins?
B and C
What is unique about B12 absorption?
it requires gastric intrinsic factor to be absorbed
What are the fat soluble vitamins and how are they digested?
A, D, E, K
bind to ingested lipids and are absorbed with their digestion products
What is vitamin B1?
thiamin
coenzyme for the pyruvate catalyzed reactions of the pentose phosphate pathway
oxidation of alcohol
What does deficiency of B1 do?
reduced capacity of cells to generate. energy
Beriberi syndrome - caused by white rice or excessive alcohol
What is vitamin B2?
riboflavin
coenzymes FMN and FAD to form FMNH2 and FADH2
What does a deficiency in B2 cause?
dermatitis
cheilosis
blurred vision
light sensitivity
What is vitamin B3?
niacin
required for synthesis of NAD+
coenzyme in glycolysis, oxidative phosphorylation, DNA repair
What does a deficiency in vitamin B3 do?
early - headache, loss of appetite
late - dermatitis, diarrhea, dementia, death
What is vitamin B5?
required for synthesis of coenzyme A
required for the metabolism of carbohydrate via the TCA cycle and all fats and proteins
What does a deficiency in vitamin B5 do?
neuromuscular degeneration
loss of appetite
mental depression
abdominal pains
What is vitamin B6?
pyridoxal
efficiently converted to the biologically active form of vitamin B6, pyridoxal phosphate
this functions as a cofactor in enzymes involved in transamination reactions and glycogenolysis
What happens during a deficiency of vitamin B6?
infants - nervous irritability, anemia
adults - increased risk of heart disease
What is vitamin B7?
biotin
coenzyme for carboxylation, decarboxylation, deamination
essential for Krebs cycle
What happens during a deficiency of vitamin B7?
scaly skin, muscle pains, nausea, elevated blood cholesterol levels
What is vitamin B12?
cyanocobalamin
coenzyme in all cells
important in DNA synthesis in bone marrow
What happens during B12 deficiency?
pernicious anemia
neurological disturbance
What is vitamin C?
ascorbic acid
antioxidant
enhances iron absorption and bioavailability
essential in conversion of tryptophan to serotonin and of cholesterol to bile salts
What happens during vitamin D deficiency?
joint pains, poor bone growth, poor wound healing, more susceptible to infection
What is vitamin A?
retinol
consists of three biologically active molecules (retinol, retinal, retinoic acid)
required for photoreceptor pigments synthesis, integrity of skin, and reproductive function
antioxidant
essential for normal bone development
What happens during vitamin A deficiency?
night blindness
epithelial changes
increases infections
What is vitamin D?
antirachitic factor
steroid hormone that functions to regulate specific gene expression following interaction with its intracellular receptor
functions primarily to regulate calcium and phosphorous homeostasis
increases calcium blood levels by enhancing absorption of calcium
mobilizes calcium from the bone with PTH
What results from vitamin D deficiency?
antisterility factor
antioxidant removing free radicals
What results from Vitamin E deficiency?
hemolysis of RBCs, fragile capillaries
What is vitamin K
coagulation factor
intermediate in ETC
essential for formation of clotting proteins
involved in oxidative phosphorylation in all cells
What happens in vitamin K deficiency?
easy bruising and bleeding
What minerals are found in the body? (7)
calcium phosphorous potassium sulfur sodium chloride magnesium
What do minerals do?
work with nutrients to ensure proper body functioning
not used for fuel
What do ca, p, and mg all do?
harden bone
What do na and cl do?
help maintain normal osmolarity, water balance, and are essential in nerve and muscle function
Why must mineral uptake and excretion be balanced?
to prevent toxic overload
How are most ions found in the body?
ionized in fluids
bound to organic compounds to form phospholipids, hormones, enzymes, and other functional proteins
What is the respiratory zone?
site of gas exchange
consists of bronchioles, alveolar ducts, and alveoli
What is the conducting zone?
conduits for air to reach the sites of gas exchange
includes all other respiratory stuctures (nose, pharynx, trachea)
What is the major function of the respiratory system?
supply the blood with oxygen and dispose of CO2
What are the four things that must happen for respiration?
pulmonary ventilation - air into and out of lungs
external respiration - gas exchange between lungs and blood
transport - of CO2 and O2 between lungs and tissues
internal respiration - gas exchange between blood and tissues
What are the functions of the nose?
providing an airway for respiration
moistening and warming the entering air
filtering inspired air and cleaning it of foreign matter
serving as a resonating chamber for speech
housing olfactory receptor
Describe the vestibule of the nose
nasal cavity superior to the nares
What are the vibrissae of the nose?
hairs that filter coarse particles from inspired air
What are the olfactory mucosa of the nose?
lines the superior nasal cavity
contains smell receptors
What is the respiratory mucosa?
lines the balance of the nasal cavity
glands secrete mucus containing lysozyme and defensins to destroy bacteria
What happens to inspired air?
humidified by high water content in nasal cavity
warmed by rich plexuses of capillaries
What do ciliated mucosal cells do?
remove contaminated mucus
What do the nasal conchae do?
increase mucosal area
enhance air turbulence and help filter air
filter, heat, moisten air upon inspiration
reclaim heat and moisture during exhalation
What do sinuses do?
lighten the skull and help warm and moisten air
Describe the nasopharynx
strictly an air passageway
lined with pseudostratified columnar epithelium
closes during swallowing
pharyngeal tonsil
Describe the oropharynx
common passageway for food and air
stratified squamous epithelium
palatine and lingual tonsils
Describe the laryngopharynx
common passageway for food and air
extends to larynx, where food and air diverge
What are the functions of the larynx?
provide a patent airway
act as a switching mechanism to route air and food into proper channels
voice production
connected to hyoid bone
What are the cartilages of the larynx?
shield-shaped anterosuperior thyroid cartilage w/ midline laryngeal prominence (adam’s apple)
cricoid cartilage
arytenoid, cuneiform, corniculate cartilages
epiglottis
Describe the vocal ligaments
elastic fibers that form mucosal folds
vibrate to produce sound as air rushes up from the lungs
What are the false vocal cords?
mucosal folds superior to true vocal cords
medial opening between them is the glottis
play no part in sound production
Define speech
intermittent release of expired air while opening and closing the glottis
Define pitch
determined by the length and tension of the vocal cords
Define loudness
depends upon the force at which the air rushes across the vocal cords
How does the pharynx participate in vocal production?
resonates, amplifies, and enhances sound quality
sound is shaped by pharynx, tongue, soft palate, lips
When is the larynx closed?
coughing
sneezing
Valsalva’s maneuver
