Intro Flashcards
4 main functions of the digestive tract
-digestion
-absorption
-motility
-elimination of waste
The process from digesting to elimination of waste takes about
12-38 hours
Digestion is
The break down / conversion of food to a form the body can absorb
Absorption is the process where
Nutrient pass across mucosal cells in the GIT epithelium and into the body
Enzymes help to
Catalyze / speed up chemical reactions involved in the breakdown of feed substances
Four areas where enzymes are secreted to aid in digestion
-mouth
-stomach
-pancreas
-small intestine
The oral cavity includes (3)
-teeth
-tongue
-pharynx
In birds, the oesophagus is
Enlarged to a Crop
The small intestine is made of three parts:
-duodenum
-jejunum
-ileum
Fermentation in fore-gut fermenters takes place before
Reaching the glandular stomach and small intestine
In hinds-gut fermenters, fermentation takes place in
The large intestine and caecum (ie. AFTER food has passed through the stomach and small intestine)
The cardiovascular system aids in digestion by
Supplying digestive organs with O2 and energy rich blood
The endocrine system aids in digestion by
Regulating digestive gland and accessory organ secretion via hormones
The integument system aids in digestion by
Protecting digestive organs
The lymphatic system aids in digestion by (3)
-defending against entry of pathogens
-lipid absorption via lacteals
-transportation of lipids to circulation via lymphatic vessels
The muscular system aids in digestion by (2)
-providing support and protection to abdominal organs
-aid in defecation
The intrinsic (enteric) nervous system is located
Inside the GIT
The nervous system aids in digestion by
Regulating secretions and muscle contraction
The extrinsic (autonomic) nervous system is located
Outside the GIT
The respiratory system aids in digestion by (2)
-providing O2
-removing CO2
The skeletal system aids in digestion by
Protecting and supporting digestive organs
Homeostasis is the
Maintenance of a relatively constant internal environment
The urinary system aids in digestion by
Calcium absorption in the small intestine via vitamin D activation
Homeostasis requires (3)
-consistent monitoring (usually via negative feedback)
-capacity to make changes and adjustments (via integrated endocrine and neural responses)
-defence against the external environment (ie. microbes, temperature, and water)
The ingestion of feed will initially trigger these three responses
-endocrine
-neural (neurotransmitter and neurohormone)
-Paracrine response (hormones acting locally)
The GIT also plays a role in (2)
-fluid and electrolyte balance
-immunity
Enterocytes rely on food to maintain
Tight junctions between cells
Without food, enterocytes cannot maintain tight junctions between cells causing
Increase in permeability —> bacterial translocation —> sepsis
When bacteria enters the blood stream it is called
Sepsis
Colic is (2)
-NOT a diagnosis
-a collection of clinical signs and symptoms indicating abdominal pain
Mechanical processes of digestion include (8)
-prehension
-mastication
-deglutition
-rumination
-storage
-motility of the wall (ie. peristalsis)
-defecation
-vomiting
The stomach releases (2)
-pepsinogen (enzyme precursor)
-acid (non-enzymatic secretion that activates pepsinogen)
Acid activates ___ to form ___ which helps to ___
Pepsinogen; Pepsin; break down peptide bonds for digestion of protein
Secretory processes can be ___ glands or ___ glands
External; Internal
External glands (ie. outside the GIT) include (3)
-salivary glands
-liver
-pancreas
Internal glands (ie. within the GIT) include (2)
-stomach
-small intestine
A community of organisms living together in a specific habitat is called the
Microbiome
The microbiota is ___ and includes (5)
All living members forming the Microbiome
-bacteria
-Protozoa
-archaea
-fungi
-algae
