Chapter 5 System 8 Digestive and 9 Excretory Flashcards
Absorption
Is the process in which the digested nutrients are transferred from the intestines to the blood or lymph vessels
Alimentary canal
Aka gastrointestinal or digestive tract
Consists of the mouth, pharynx, esophagus, stomach, and small and large intestine
A muscular tube that is 5x as long as a person is tall
Lips to anus
Accessory digestive organs
Consists of the teeth, tongue, salivary glands, pancreas, liver, and gallbladder
Oral cavity
Or mouth, prepares food for entrance into the stomach
The main functions of the digestive system are ____ and ____.
Digestion and absorption
Saliva
Produced by the salivary glands in the mouth and contains enzymes that begin to digest carbohydrates
Masticated
Chewing food
Bolus
The action of the teeth, tongue, and saliva prepared the food into a soft ball
The wall of the alimentary canal consists of what four distant layers?
Mucosa
Submucosa
Muscular layer
Serous layer
Mucosa
Innermost layer
Or mucous membrane, is made up of epithelial cells, connective tissue, and a variety of digestive glands.
This layer protects the underlying tissues and functions to carry on secretion and absorption
Submucosa
Second innermost layer
Consists of connective tissue, nerves, blood vessels, and lymph vessels that serve to nourish the surrounding tissue and carry away absorbed material
Muscular layer
3rd innermost layer
Has two layers of smooth muscles
One layer decreases the diameter
The other shortens the length
Serous layer
Outermost layer
On the stomach and intestines
This layer is continuous with the peritoneum that lines the abdominal cavity
Perstalsis
Is the wavelike muscular action of the alimentary canal
Digestion
Is the process of converting food into substances capable of being used by the cells for nourishment
Chyme
The mixture of digestive juices, mucus, and food material
Stomach
Where the bolus is churned with gastric juices secretes from glands in the wall of the stomach.
Hydrochloric acid
Protein digesting enzymes
Pyloric sphincter ***
Determines how long food is held in the stomach
voluntary muscle
Small intestine
Is the longest part of the alimentary canal
Duodenum
Jejunum
Ileum
Thousands of glands in the walls produce intestinal juices
Also secretions of bile from the liver and pancreatic fluids
Bile
A bitter, alkaline, yellowish-brown fluid
From the liver and gallbladder is carried through the common bile duct
Essential for the break down of fats
Pancreatic fluid
Enters the duodenum by way of the pancreatic duct
Contains enzymes that act to digest proteins, carbohydrates, and fats
Villi
The small intestine is lined with small, fingerlike projections covering the intestine wall
Greatly increase the surface area available for absorption
Lacteals
Network of blood capillaries and lymph
Cisterna chyli and the thoracic duct
Nutrients absorbed by the lymph flow through the cisterna chyli and the thoracic duct before entering the systemic circulation
The functions of the colon
Storing, forming, and excreting waste products of digestion and regulating the body’s water balance
The bacterial action in the colon also synthesizes some B-complex vitamins and vitamin K, which is reabsorb we into the bloodstream
Saliva
Salivary glands
Mouth
Enzymes; salivary, amylase
Begins digestion of starch into simple sugars
Gastric juice
Stomach
Stomach wall
Pepsin
Begins digestion of protein into amino acids
Pancreatic juice
Pancreas
Small intestine
Enzymes; Amylase, Trypsin,
Lipase
Starches, proteins, fats
Juice from small intestine
Small intestine
Enzymes; lactase, maltase, sucrase
Breaks down complex carbohydrates to simple sugars
Bile from liver
Small intestine
No enzymes
Breaks down fats into fatty acids
The path food travels
Mouth (bolus)- esophagus- cardiac sphincter- stomach (chyme)- pyloric sphincter- duodenum- jejunum- ileum- iliocecal valve- cecum- ascending colon- transverse colon- descending colon- sigmoid colon- rectum- anal canal- anus
Metabolic waste
Are products formed from cell metabolism
The function of the excretory system (including the urinary system)
Is to eliminate or excrete metabolic wastes and undigested food from the body
The organs of the excretory system are
The kidneys, liver, skin,
large intestine, and lungs
Kidneys
Excrete uric acid, urea, electrolytes, water, and other wastes through the process of urination
Beaned shaped organs
Blood filtration
maintain the body’s water balance and acid-base balance
production of the hormone Renin
Liver
Produces urea, which is returned to the blood to be excreted by the kidneys
Also discharges bile through the gallbladder and into the intestine
one of the largest organs of the digestive track
neutralizes or detoxifies toxic substances
stores vitamins A, B, B12, and glycogen
main excretory function is in the form of urea
Skin
Eliminates water and heat through the process of perspiration
Large intestine
Discharges food wastes through the process of defecation
Lungs
Exhale carbon dioxide and water vapor through external respiration
The urinary system includes
2 kidneys, two ureters, the bladder, and a urethra
Nephron
Is the functional unit of the kidney
2-3 million nephrons in the kidney
Filters 40-50 gallons of blood
99% of the fluid is reabsorbed into the bloodstream
Ureters
Are tubes that carry urine from the kidneys to the bladder
Bladder
Where the urine is stored
A hollow organ that is an involuntary muscles
Can hold a pint of urine
Renin
a hormone produced by the kidney
acts to regulate the blood pressure
