Digestive and respiratory Flashcards
animals whose primary food source is plant- based.
herbivores
animals that eat other animals
Carnivores
are those that rely entirely on animal flesh to obtain their nutrients
obligate carnivores
are those that also eat non-animal food in addition to animal food
Facultative carnivores
are animals that eat both plant- and animal-derived food
omnivores
Many aquatic animals are ____, which eat small organisms or food particles suspended in the water.
suspension feeders
feeders like the humpback whale shown above move water through a filtering
structure to obtain food.
filter feeders
animals that live in or on their food source, eating their way through the food
substrate feeder
suck nutrient-rich fluid from a living host
fluid feeder
eat relatively large pieces of food
bulk feeders
is found in organisms with only one opening for digestion.
gastrovascular cavity
is a more advanced system: it consists of one tube with a mouth at one end and an anus at the other.
alimentary canal
this type of digestive system consists of one stomach chamber. Humans and many animals (herbivores) have this system
monogastric: single chambered stomach
The stomach of birds has two chambers:
proventriculus and gizzard
are mainly herbivores like cows, sheep, and goats, whose entire diet consists of eating large amounts of roughage or fiber.
ruminants
The digestive enzymes of these animals cannot break down cellulose, but microorganisms present in the digestive system can. Therefore, the digestive system must be able to handle large amounts of roughage and break down the cellulose.
pseudo-ruminant
is a muscular tube lined by a mucous membrane and
features a basic histological organization that is similar across all
of its segments of the tract.
GI tract
four layers of the gi tract
adventitia, submucosa, muscularis externa (2 layers)
consists of connective tissue containing
blood vessels, nerves, and fat.
adventitia
is a thick connective tissue layer that
contains arteries, veins, lymphatics, and nerves.
submucosa
surrounds the submucosa and is
composed of two muscle layers, the inner circular layer and
outer longitudinal layer.
muscularis externa
There
are four distinct types of mucosal variations:
Protective mucosa, Secretory mucosa, Absorptive mucosa, Absorptive/protective mucosa
is characterized by a stratified squamous
epithelium. It is found in the oral cavity, pharynx,
esophagus, and anal canal.
Protective mucosa
contains cells that are responsible for the
secretion of digestive enzymes. It is found exclusively in the
stomach
Secretory mucosa
contains two key structures, crypts and
villi, and is responsible primarily for absorbing digested
nutrients. It is found along the entirety of the small intestine.
Absorptive mucosa
specializes in water
absorption and mucous secretion. It is found in the large
intestine.
Absorptive/protective mucosa
is the most widespread
epithelium. This type of epithelia varies in thickness depending on
the number of cell layers present.
Stratified squamous epithelium
are mitotically active and
replace the cells of the epithelium which are lost by “wear and
tear”.
basal cell
is followed by layers of cells with
polyhedral outlines.
basal cell layer
is seen as single layer of tall, closely
packed cells, aligned like soldiers in a row. This epithelial type
lines the digestive tract from the stomach to the rectum.
Simple columnar epithelium
are mostly associated with absorption and
secretion, and the digestive tract lining has two distinct
modifications that reflect those dual functions:
Columnar cells
microvilli and goblet cells
is the point of entry of food into the
digestive system,
oral cavity
There are three major glands that
secrete saliva:
- the parotid
- the submandibular
- the sublingual.
Saliva contains the following:
mucus, immunoglobulins, salivary amylase, lipase
The chewing and wetting action provided by the teeth and saliva
prepare the food into a mass called the
bolus
is junction that opens to both the
esophagus and the windpipe (trachea).
Pharynx
As you swallow, the top of
the windpipe moves up so that its opening, the ____, is blocked
by a cartilaginous flap called the ______
glottis, epiglottis
is a tubular organ that connects the mouth to the
stomach.
Esophagus
The smooth muscles of the
esophagus undergo a series of wave like movements
called __ that push the food toward the stomach
peristalsis
A ring-like muscle called a __ forms valves in the digestive
system.
sphincter
__ is located at the
stomach end of the esophagus.
gastro-esophageal sphincter
True or false. Many animals have a true sphincter; however, in humans, there is no true sphincter, but the
esophagus remains closed when there is no swallowing action.
True
occurs when the acidic digestive juices
escape into the esophagus.
Acid reflux or “heartburn”
is a saclike organ that secretes gastric digestive
juices.
stomach
Protein digestion is mediated by an enzyme called __ in the stomach chamber.
pepsin
Another cell type secrete hydrogen and chloride ions, which combine in the lumen to form hydrochloric acid, the primary acidic component of the stomach juices.
parietal cells
The partially digested food and gastric juice
mixture is called
chyme
is the organ where the digestion of protein, fats, and
carbohydrates is completed.
small intestine
The small intestine is a long tube-like
organ with a highly folded surface containing finger-like
projections called the
villi
The apical surface of each villus has
many microscopic projections called.
microvilli
The human small intestine is over 6m long and is divided into
three parts:
a. duodenum
b. jejunum
c. ileum
is produced in the liver and stored and concentrated in the
gallbladder.
bile
reabsorbs the water from the
undigested food material and processes the waste material.
large intestine
three parts of the large intestine
cecum, colon, rectum
is an opening at the far-end of the digestive tract and is
the exit point for the waste material.
anus
Two sphincters between the
rectum and anus control elimination:
the inner sphincter is
involuntary and the outer sphincter is voluntary.
are organs that add secretions (enzymes) that catabolize food into nutrients.
Accessory Organs
is the largest internal organ in humans and it plays a very
important role in digestion of fats and detoxifying blood.
liver
is a small organ that aids the liver by storing bile
and concentrating bile salts.
gallbladder
is the process
of taking in food through the mouth.
ingestion
is the mechanical and chemical break down of food into
small organic fragments.
digestion
The disaccharides are broken down
into monosaccharides by enzymes called
maltases, sucrases,
and lactases
is a process in which large lipid
globules are broken down into several small lipid globules.
emulsification
contain triglycerides,
cholesterol, and other lipids and have proteins on their surface.
Chylomicrons
Fat soluble
vitamins are absorbed in the same manner as
lipids
Water-soluble vitamins can
be directly absorbed into the bloodstream from the
intestine
is a condition where
the feces are hardened because of excess water removal in the
colon.
constipation
if enough water is not removed from the feces,
it results in
diarrhea
is elimination of food by forceful expulsion
through the mouth.
Emesis, or vomiting
The source of O2, called the
respiratory medium,
The part of an animal’s body where gas is exchanged with the
surrounding environment is called the
respiratory surface.
is a slow, passive transport process. In order
for diffusion to be a feasible means of providing oxygen to the cell,
the rate of oxygen uptake must match the rate of diffusion across
the membrane.
diffusion
Systems of Gas Exchange
Direct Diffusion, Skin and Gills, Tracheal Systems in Insects, Mammalian Respiratory System
is the most
abundant cartilage type in the body.
hyaline cartilage
The respiratory or gas-exchange region of the lung is composed of
millions of
alveoli
Tissue types in the respiratory system
ciliated pseudostratified columnar epithelium, hyaline cartilage, Simple squamous epithelium.
During inhalation, air enters the body through the __ located just inside the nose.
nasal cavity
is coated with mucus to seal the
tissues from direct contact with air.
respiratory tract
From the nasal cavity, air passes through the __ and
the ___, as it makes its way to the __
pharynx (throat); larynx (voice box); trachea
The main function of the trachea
to funnel the inhaled air to the lungs and the exhaled air back out of the body.
True or false. The lungs are not identical
true
The ___ is larger and
contains three lobes, whereas the smaller __ contains two
lobes.
right lung; left lung
In the lungs, air is diverted into smaller and smaller passages, called
brochi
Each bronchus divides into
secondary bronchi, then into tertiary bronchi, which in turn divide,
creating smaller and smaller diameter ____ as they split
bronchioles
bronchioles
with a diameter smaller than 0.5 mm are the
respiratory
bronchioles
subdivide into microscopic branches
called respiratory bronchioles.
terminal bronchioles
___ are attached
to the end of each bronchiole. At the end of each duct are
approximately 100 ___, each containing 20 to 30 ___
alveolar ducts; alveolar sacs; alveoli
Gas exchange
occurs only in
alveoli
Alveoli are in direct contact with ____
of the circulatory system.
capillaries (one-cell thick)
The air that organisms breathe contains ___ such
as dust, dirt, viral particles, and bacteria that can damage the
lungs or trigger allergic immune responses.
particulate matter
The breathing mechanism involves two processes:
- Inspiration
- Expiration
In the process of ____, there would be a
contraction of muscles attached to the ribs on the outer side
which pulls out the ribs and results in the expansion of the chest
cavity.
inspiration or inhalation
The ___ process is considered once after the gaseous
exchange occurs in the lungs and the air is expelled out.
expiration process
The neurons mainly responsible for regulating breathing are in the ___, near the base of the brain
medulla oblongata
wheezing and breathlessness caused by a
narrowing of the airways
asthma
inflammation of the lung’s larger airways
bronchitis
disease of the alveoli (air sacs) of the lungs
ephysema
an allergic reaction to pollen, dust or other
irritants
hay fever
caused by viruses
influenza
inflammation of the voice box (larynx)
laryngitis
infection of the lung
pneumonia
