which muscles are activated during forced expiration?

the internal intercostal muscles and abdominal wall muscles

which of the following arterial blood levels is the most powerful respiratory stimulant?

rising CO₂ levels

which if the following initiate(s) inspiration?

ventral respiratory group (VRG)

which of the following stimuli is the most powerful respiratory stimulant to increase respiration?

rising carbon dioxide levels

which blood vessels supply oxygenated systemic blood to the lung tissue?

bronchial arteries

which of these structures is/are NOT properly matched with one of its/their functions?

paranasal sinuses: surface for odor receptors

the alveolar ducts are part of the conducting zone. T/F

false

which of the following would NOT be helpful in identifying the left lung?

horizontal fissure

emphysema can result in an_________.

increased level of carbaminohemoglobin

increased level of deoxyhemoglobin

increased likelihood of the skin of Caucasians developing a slightly blue coloration

all of the listed responses are correct

which of the following cavaties surround(s) the lung alone?

pleural cavities

what area in the brain sets the respiratory rhythm?

ventral respiratory group (VRG)

inspiratory neurons send information to the diaphragm via what nerve?

phrenic nerve

what directly stimulates the central chemoreceptors, thus increasing respiraition?

H+ (hydrogen ions)

which receptors inhibit inspiration during hyperinflation of the lungs?

pulmonary stretch receptors in joints, neural input from the motor cortex, and other factors

a homeostatic control mechanism controls respiration. what acts as the effector(s) in this system?

respiratory muscles

which of the following is NOT a benefit of breathing through the nose?

destruction of pathogens entering the nasopharynx

which of the following inhibits/reduces the respiratory rate?

stimulation of stretch receptors in the lungs

quiet inspiration is _______, and quiet expiration is _______.

an active process; a passive process

the division between the upper and lower respiratory system is around the nasopharynx.

false

which of the following statements about the pleurae is NOT true?

the pleurae create one continuous cavity for both lungs

which of these structures forms a complete ring around the airway?

cricoid cartilage

which of the following would include the loss of oxygen from the hemoglobin and the blood?

a drop in blood pH

what type of epithelial tissue forms the walls of the alveoli?

simple squamous epithelium

what part of the larynx covers the laryngeal inlet during swallowing to keep food out of the lower respiratory passages?

epiglottis

which of the following is/are part(s) of the respiratory zone structures?

alveoli

which of the following modifies and smoothes the respiratory pattern?

pontine respiratory centers

which of these cells would be most effective in the ingestion and disposal of microorganisms that may enter the alveoli?

alveolar macrophages

which of the following regions contains the opening of a canal that equalizes pressure in the middle ear?

nasopharynx

what is the primary form in which oxygen is carried in blood?

chemically bound to hemoglobin

what is the most common method of carbon dioxide transport?

as bicarbonate ions in the plasma

in children with infant respiratory distress syndrome (IRDS), the walls of the alveoli cling to each other and make them difficult to inflate. it is common in babies born prematurely. what cells in these infants are NOT fully developed and are NOT doing their job?

type II alveolar cells

what is the most powerful respiratory stimulant in a healthy person?

arterial blood carbon dioxide level

during inhalation,

the diaphragm and rib muscles contract

from which structures do oxygen molecules move from the lungs to the blood?

alveoli

which statement is correct?

in the blood, oxygen is bound to hemoglobin, a protein found in red blood cells

after blood becomes oxygenated,

it returns to the heart, and is then pumped to body cells

hemoglobin

is a protein that can bind four molecules of oxygen

which of the following is NOT a function of the nasal conhae

routing air and food into proper channels

which form of CO₂ transport accounts for the least amount of CO₂ transported in blood?

dissolved in plasma

which of the following is NOT a structural modification of the small intestine that increases surface area?

rugae

what role of the stomach is essential to life?

production of intrinsic factor

the _____ is the serous membrane that lines the abdominal organs.

visceral peritoneum

which layer of the alimentary canal is responsible for segmentation and peristalsis?

muscularis externa

the pancreas secretes ______.

procarboxypeptidase

which organ of the digestive tract is the body's major digestive organ?

small intestine

what triggers the release of secretin from the small intestine?

the presence of acidic, fatty chyme in the small intestine

salivation is controlled almost entirely by the nervous system. which of the following stimuli would inhibit salivation?

fear

HCI secretions convert pepsinogen to the active hormone pepsin. what cells in the gastric pits produce pepsinogen?

chief cells

in response to a steak dinner, certain secretions are needed to aid digestion. what cells in the pancreas would provide these secretions?

acinar cells

an increase in HCI (hydrochloric acid) arriving in the duodenum would stimulate which hormone that would help to counteract the effects of HCI?

secretin

the secretion in the large intestine consists of which of the following?

bicarbonate - potassium-rich mucus

which layer of the alimentary canal contains not only glands and blood vessels but also a nerve plexus that helps regulate digestive activity?

submucosa

which digestive process does NOT occur in the mouth?

segmentation

which enzyme(s) is/are responsible for the chemical breakdown of carbohydrates?

amylases

which of the following is the primary physiological function of the large intestine?

water absorption and feces elimination

carbohydrates are digested into_____.

monosaccharides

what is a major function of pancreatic juice?

neutralizing chyme entering the small intestine from the stomach

______ and ______ are water-soluble vitamins that are absorbed in the small intestine.

B complex and C vitamins

which layer of the stomach contains the gastric pits that secrete mucous, acid, and digestive enzymes?

mucosa

the ______ circulation drains all of the organs of the digestive system.

hepatic portal

which of the following does NOT describe a basic regulator of digestive control?

conscious neural control

which of the following is NOT a means of mechanically breaking down food?

peristalsis

what type of blood capillary located in this sublayer is uniquely suited for absorption of nutrient material?

fenestrated

which of the following is NOT a function of saliva

saliva contains enzymes that begin the chemical breakdown of proteins

which chemical activated the transformation of trypsinogen to trypsin?

enteropeptidase

which of the following is NOT a characteristic of the stomach?

the stomach releases enzymes to digest carbohydrates

which of the following functions is NOT correctly matched with its description?

propulsion : physical breakdown of ingested food in the GI tract

bacteria that resides in the large intestine make vitamin C.

false

which of these best describes a lacteal?

a lymphatic vessel designed to help introduce fats to the blood

which major process involves the removal of water from intestinal contents?

absorption

which of the following is NOT a function of the large intestine?

production of intrinsic factor

which area of the stomach adjoins the small intestine?

pylorus

what structural modification of the small intestine slows the movement of chyme through the lumen?

circular folds

the _____ is the first segment of the small intestine.

duodenum

which of the following processes occurs in the stomach?

mechanical digestion

bile is produced by the _____ under hormonal influence of _____.

liver; secretin

most absorption of nutrients occurs in the _____.

jejunum

which layer of the digestive tract controls digestive propulsion?

muscularis externa

which of the following is NOT a secretin of the pancreas?

bile

which layer of the alimentary canal is constructed from either stratified squamous or simple columnar epithelium?

mucosa

which of these structures is found in the stomach but nowhere else in the alimentary canal?

serosa

which cells in the small intestine's mucosa secrete mucus?

goblet cells