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Gabriela Samson P:1 Digestive & Urinary System - Coggle Diagram
Gabriela Samson P:1 Digestive & Urinary System
Major functions of the digestive system
Lips:
Highly mobile structures that surround the mouth opening
Involved in chewing and expression
Contain sensory receptors to detect the temperature and
texture of food
form the lateral walls of the mouth
Tongue:
Cheeks:
Thick, muscular organ, composed of skeletal muscle
The narrow space between the teeth, cheeks, and lips is called the vestibule
Covered by a mucous membrane
Oral cavity is the chamber between the palate and tongue
Surface contains projections called papillae, which provide
friction for moving food in the mouth
Surrounded by lips, cheeks, tongue, and palate
Taste buds occur along the sides of the papillae
Functions: receives food, and begins mechanical digestion by mastication (chewing)
Attached to the floor of the mouth by lingual frenulum
First portion of the alimentary canal
Lingual tonsils are lymphatic tissues located at the root of the tongue
The mouth
Teeth:
The wall of the alimentary canal consists of the same 4 layers throughout its length, with variations according to the functions of specific sections of the canal
Two sets of teeth develop in sockets within the alveolar processes of the maxillary and mandibular bones
~8 meters long
The 20 primary (deciduous) teeth are shed in the order they
appeared, and are replaced by 32 secondary (permanent) teeth
Food passageway between the mouth and anus
Through actions of chewing, teeth break food into smaller pieces, beginning mechanical digestion
Muscular tube that passes through thoracic and
abdominopelvic cavities
Different teeth are adapted to handle food in different ways, and include incisors, cuspids, bicuspids, and molars
Alimentary Canal:
Teeth start the process of mechanical digestion by breaking down larger pieces of food into smaller pieces
The digestive system consists of the alimentary canal (digestive tract), leading from mouth to anus, and several accessory organs whose secretions help the processes of digestion
Mechanical digestion makes chemical digestion easier, by
increasing surface area for enzyme access to food particles
Chemical digestion breaks down large nutrient molecules into smaller chemicals, by breaking chemical bonds
The salivary glands (Parotid, Submandibular, Sublingual glands) secrete saliva, which moistens and dissolves food particles, binds them together, aids in tasting, helps to cleanse the mouth and teeth, and begins carbohydrate digestion
Mechanical digestion breaks down large pieces of food into
smaller ones; chemical composition is not changed by this process
Salivary Secretions:
The digestive system carries out the process of digestion
Salivary glands contain serous cells that produce a watery fluid containing salivary amylase, and mucous cells that produce lubricating and binding mucus
Digestion: mechanical and chemical breakdown of foods and
absorption of nutrients
Amylase breaks down starch into disaccharides
Layers of the GI tract (including stomach)
Consists of 2 layers of smooth muscle: inner circular layer and outer longitudinal layer
Propels food through the canal
Muscularis
Serosa:
Vessels transport absorbed nutrients away from digestive organs
Outer serous layer, or visceral peritoneum
Nourishes the surrounding layers of the canal
Protects underlying tissues, and secretes serous fluid to reduce friction between organs
Consists of loose connective tissue, housing blood and lymphatic vessels, nerves, and glands
Movements of the Tube
Lies under the mucosa
The motor functions of the alimentary canal are of 2 types:
Submucosa
Mixing movements:
In some regions, the mucosa is modified into folds or projections, which increase surface area
Occur when smooth muscles contract rhythmically in small
sections of the tube
Carries on secretion and absorption of dietary nutrients
Segmentation in the small intestine aids mixing by alternately contracting and relaxing the smooth muscle in each area
Protects tissues of the canal
Propelling movements:
Consists of epithelium, underlying connective tissue, a little smooth muscle
Include a wavelike motion called peristalsis
A mucous membrane that surrounds the lumen of the tube
A ring of contraction in a portion of the tube occurs, while
relaxation occurs ahead of the ring
The inner layer of the wall
This allows a mass of food to be propelled to the next segment of the tube
Mucosa:
The wall of the alimentary canal consists of the same 4 layers throughout its length, with variations according to the functions of specific sections of the canal
Structure of the Wall of the Alimentary Canal
Location of digestion and absorption of each macromolecule
The mouth
First portion of the alimentary canal
The wall of the alimentary canal consists of the same 4 layers throughout its length, with variations according to the functions of specific sections of the canal
Functions: receives food, and begins mechanical digestion by mastication (chewing)
~8 meters long
Surrounded by lips, cheeks, tongue, and palate
Food passageway between the mouth and anus
Muscular tube that passes through thoracic and
abdominopelvic cavities
Oral cavity is the chamber between the palate and tongue
The narrow space between the teeth, cheeks, and lips is called the vestibule
Alimentary Canal:
Structure of the Small Intestinal Wall
The digestive system consists of the alimentary canal (digestive tract), leading from mouth to anus, and several accessory organs whose secretions help the processes of digestion
The inner wall of the small intestine is lined with finger-like
intestinal villi, which greatly increase the surface area available for absorption and aid in mixing actions
Chemical digestion breaks down large nutrient molecules into smaller chemicals, by breaking chemical bonds
Each villus consists of simple columnar epithelium with a core of connective tissue, housing blood capillaries and a lymphatic capillary called a lacteal
Mechanical digestion breaks down large pieces of food into
smaller ones; chemical composition is not changed by this process
Blood capillaries and lacteals transport absorbed dietary nutrients out of the alimentary canal
The digestive system carries out the process of digestion
Digestion: mechanical and chemical breakdown of foods and
absorption of nutrients
Major organs of the urinary systems
Tubular secretion:
Process by which additional wastes from the blood are
moved from the peritubular capillaries into the renal tubule
Most useful substances are returned to blood by this process
Amount of a substance excreted in urine:
Process by which useful filtered substances are transported
from the filtrate to the blood of the peritubular capillaries
Amount filtered by glomerulus;– amount reabsorbed by renal tubule; + amount secreted by renal tubule
Tubular reabsorption:
Urea and Uric Acid Excretion-By-product of amino acid metabolism
Produces about 180 liters of fluid per day
After glomerular filtration, 40-60% of urea is reabsorbed
Filtrate then moves into the renal tubules
Remaining urea is excreted in the urine
Glomerulus filters water and small substances from blood
plasma, and transports it into the glomerular capsule as glomerular filtrate
Uric acid:By-product of nucleic acid metabolism;Most is reabsorbed by active transport;
First step of urine formation
Small amount is secreted into the renal tubule, and then
excreted in the urine
Glomerular filtration:
Ureter:Muscular tube that conveys urine from the kidney to the urinary bladder
Tubular secretion
Begins as the funnel-shaped renal pelvis
Tubular reabsorption
Due to the angle at which ureters enter the urinary bladder,
wall of the bladder acts as a one-way valve, propelling the urine into the bladder, but preventing it from flowing backward
Glomerular filtration
Urinary bladder:Hollow, distensible, muscular organ lying in the pelvic cavity
Urine formation involves 3 processes:
Stores urine, and excretes it through the urethra
Urine Formation
Portion of the lower bladder forms the internal urethral
sphincter
Disorders of the digestive and urinary systems
Colon Diseases- Colo rectal cancer- uncontrolled cell growth in the colon.
Diverticulitis- Pounches form on the wall of the colon.
Peptic Ulcers- Sores that develop in the lining of the stomach or the duodenum.
Bladder Cancer- A person with bladder cancer will have one or more tumors in the bladder.
Inflammatory Bowel Disease (IBD)- A chronic complex intestinal condition that causes inflammation in the digestive tract, includes crone's disease and ulceration colitis.
Urinary Tract Infection (UTI)- Urinary tract infections are very common in women. About 40% of women will experience a UTI at least once.
Gastroesophageal Reflux Disease (GERD)- A chronic disease that occurs when the esophageal sphincter relaxes, allowing the contents of the stomach to move back into esophagus.
Kidney Stones- Urine contains many dissolved minerals and salts. When the urine has high levels of minerals and salts, hard stones can form.
Cholecystitis- An inflammation of the gall bladder.
Major organs of the digestive system
Functions of the small intestine:
Receives chyme from stomach
Fills a large part of the abdominal cavity
Receives pancreatic juice from pancreas and bile from liver and gallbladder
Small intestine is a long tubular organ, which runs from the
stomach to the beginning of the large intestine
Finishes digestion of nutrients that arrive in the chyme
Lower esophageal (cardiac, cardioesophageal) sphincter helps to prevent regurgitation of the stomach contents into the esophagus
Absorbs digestive end products
Transports the remaining residue to the large intestine
Mucous glands scattered throughout submucosa produce
mucus to moisten and lubricate the inner lining of the tube
Extends downward through an opening in the diaphragm
Small intestine consists of the duodenum, jejunum, and ileum
Straight, collapsible food passageway leading to the stomach
Duodenum: the shortest and most fixed portion of the small intestine; the stomach empties chyme directly into the duodenum
Esophagus:
Jejunum: makes up the proximal two-fifths of the small intestine, has a slightly larger diameter than the ileum, and is more active in the digestion process
Laryngopharynx: bottom portion, passageway to esophagus
Ileum: most distal portion
Oropharynx: middle portion, passageway for food and air
The jejunum & ileum are suspended from the posterior abdominal wall by a double-layered fold of peritoneum called mesentery
Nasopharynx: top portion, air passage behind nasal cavity
The mesentery contains blood vessels, nerves, and lymphatic vessels that serve the intestinal wall
Divided into 3 portions:
Greater omentum drapes over the intestine; it is a double fold of peritoneal membrane
Connects the nasal and oral cavities with the larynx and
esophagus
The inner wall of the small intestine is lined with finger-like
intestinal villi, which greatly increase the surface area available for absorption and aid in mixing actions
Structure of the Pharynx:
Each villus consists of simple columnar epithelium with a core of connective tissue, housing blood capillaries and a lymphatic capillary called a lacteal
Esophagus: muscular tube leading from pharynx to stomach
Blood capillaries and lacteals transport absorbed dietary nutrients out of the alimentary canal
Pharynx (throat): cavity lying posterior to the mouth
Pharynx and Esophagus
Major functions of the urinary system
– amount reabsorbed by renal tubule
amount secreted by renal tubule
Amount filtered by glomerulus
Glomerular filtration:
Amount of a substance excreted in urine:
Process by which additional wastes from the blood are
moved from the peritubular capillaries into the renal tubule
First step of urine formation Involves filtration of water and small dissolved substances from the glomerular capillaries into the glomerular capsule
Glomerular filtrate is very similar to interstitial fluid; consists
mainly of water, electrolytes, small nutrient molecules, and small waste molecules (but no large plasma proteins)
Tubular secretion:
Tubular secretion:
Most useful substances are returned to blood by this process
Reverse of tubular reabsorption
Process by which useful filtered substances are transported
from the filtrate to the blood of the peritubular capillaries
20% of plasma is filtered by the glomerulus; 80% is transported to the efferent arteriole and then to the peritubular capillaries
Tubular reabsorption:
Urine Formation
Tubular secretion transports certain substances from the
plasma of the peritubular capillaries into the fluid of the renal tubule
Help control the rate of red blood cell formation
Wastes and large molecules typically join the forming urine by tubular secretion
Remove metabolic wastes from the blood in the process,
forming urine
Regulate the volume, composition, and pH of body fluids
Functions of the kidneys:
Kidney Functions
Digestive enzymes (including names and functions)
Two nucleases break down nucleic acids to nucleotides
Proteolytic enzymes, trypsin, chymotrypsin, and
carboxypeptidase, each split certain bonds between amino acids, to break down proteins to dipeptides
Pancreatic lipase breaks down triglycerides to glycerol and fatty acids
Pancreatic juice also contains bicarbonate ions, which create an alkaline environment in the duodenum for enzyme function
Pancreatic amylase breaks down starch into disaccharides
Liver and Gallbladder
Pancreatic juice contains enzymes that digest carbohydrates, fats, proteins, and nucleic acids:
The reddish-brown liver, located in the upper right quadrant of the abdominal cavity, is the body’s largest internal organ
Pancreatic Juice
Liver Structure:
Divided into large right and left lobes, and is enclosed by a
fibrous capsule
Exocrine function is to produce pancreatic juice that aids digestion
Pancreas is both endocrine and exocrine gland
Liver Functions
Pancreas
Responsible for many metabolic activities, such as the metabolism of carbohydrates, lipids, and proteins
Amylase breaks down starch into disaccharides
Maintains proper blood concentrations of glucose and other nutrients
Salivary glands contain serous cells that produce a watery fluid containing salivary amylase, and mucous cells that produce lubricating and binding mucus
Stores glycogen, vitamins A, D, and B12, and iron
Salivary Secretions:
Synthesizes lipoproteins, phospholipids, and cholesterol
The salivary glands (Parotid, Submandibular, Sublingual glands) secrete saliva, which moistens and dissolves food particles, binds them together, aids in tasting, helps to cleanse the mouth and teeth, and begins carbohydrate digestion
Filters the blood, removing damaged red blood cells and foreign substances, and removes toxins, Role in digestion is to secrete bile
Salivary Glands
Nephron anatomy and physiology
Consists of cone-shaped structures
Renal cortex:
Renal medulla:
Surrounds the renal medulla
Each kidney has 2 major regions:
Granular appearance, due to presence of tiny, round
structures called renal corpuscles, which are part of the functional units of the kidneys, the nephrons
Renal pelvis is also the expanded superior end of the ureter
Kidney Functions
Inside the renal sinus lies a renal pelvis that is subdivided into major and then minor calyces
Functions of the kidneys:
Hilum: medial depression in kidney; leads to a hollow chamber, the renal sinus, into which blood vessels, nerves, lymphatic vessels, and the ureter enter or exit
Regulate the volume, composition, and pH of body fluids
Lateral side is convex, and medial side is concave
Remove metabolic wastes from the blood in the process,
forming urine
Kidney Structure
Help control the rate of red blood cell formation
Kidneys are retroperitoneal, behind the parietal peritoneum
Renal Blood Supply
Enclosed in a tough, fibrous capsule
The abdominal aorta gives rise to renal arteries, which supply blood to the kidneys
A reddish brown, bean-shaped organ, 12 cm long
As renal arteries pass into the kidneys, into the afferent
arterioles, which lead to the nephrons
The kidney:
Afferent arteriole gives rise to capillary cluster, a glomerulus
Kidneys
Nephron anatomy and physiology
Renal tubule consists of the following parts, in this order:
Glomerular capsule
Nephron Structure
Proximal convoluted tubule
Glomerular capsule is actually the expanded proximal end of
a renal tubule
Nephron loop (descending and ascending limbs)
Consists of cluster of capillaries, the glomerulus, and a
glomerular capsule, a cup-shaped sac that receives filtrate
Distal convoluted tubule
Filtration structure in renal cortex, which performs the first
step of urine formation
Collecting duct
Renal corpuscle:
Several distal convoluted tubules join to become a collecting
duct, which passes from the renal cortex into the renal medulla, emptying into a minor calyx at the papilla
Consists of a renal corpuscle and a renal tubule
About one million nephrons per kidney
Functional unit of kidney; can produce urine independently
Nephron:
Nephron Structure
The renal vein then joins the inferior vena cava in the
abdominal cavity
Blood not filtered by glomerulus enters efferent arteriole, into
the renal vein