Reproductive and digestive system Flashcards
(224 cards)
1
Q
When chyme enters duodenum, CCK is released what happens?
A
- Hepatopancreatic sphincter relaxes.
- Gallbladder contracts
2
Q
Full gallbladder contains how much bile?
A
- 40-70 mL.
3
Q
Enolecysittis
A
- Gallstones are so large, blockage occurs.
4
Q
Small intestine is described how?
A
- Long, muscular tube
5
Q
Where is chemical digestion completed?
A
- Small intestine
6
Q
True or False:
90% of nutrients absorption occurs in the stomach.
A
- False, Small intestine
7
Q
What are the 3 segments of the small intestine?
A
- Duodenum
- Jejunum
- Ilium
8
Q
Duodenum is located where?
A
-Segment of small intestine closest to stomach.
9
Q
How long is the duodenum?
A
- 25 cm.
10
Q
Why is the duodenum is referred to as the mixing bowl?
A
- Receives chyme from stomach and digestive secretions from pancreas and liver.
11
Q
Where is the Jejunum located?
A
Middle segment of small intestine
12
Q
How long is the Jejunum?
A
2.5 meters long
13
Q
What is area is the site of most chemical digestion and nutrient absorption?
A
Jejunum
14
Q
What is the final segment of small intestine?
A
Ileum
15
Q
What are circular folds?
A
- Transverse folds in intestinal lining.
- Permanent features that do not disappear when small intestine fills.
16
Q
What are intestinal villi?
A
Finger like projections in mucous of small intestine.
17
Q
What type of tissue covers intestinal villi?
A
Simple columnar epithelium and carpeted with microvilli that form brush border.
18
Q
What are lacteals?
A
Lymphatic vessel in each villus.
19
Q
What is the function of a lacteal?
A
Transports chylomicron that are too large to enter blood capillaries.
20
Q
Duodenal submucosal glands produce what?
A
Copious qualtities of mucus.
21
Q
When chyme arrives from stomach what happens?
A
Mucus protects epithelium from acidity of chyme.
22
Q
Mucus contains what?
A
Bicarbonate ions that raise pH.
23
Q
How much intestinal juice enters intestinal lumen each day?
A
1.8 liters
24
Q
What are functions of intestinal juice?
A
- Moistens chyme
- Assists in buffering acids
- Keeps digestive enzymes and products of digestion in solution
25
Mucosa of _______ _______ produces few enzymes involved in chemical digestion.
small intestine
26
What are functions of the brush border enzymes?
- Intergral membrane proteins on intestinal microvilli.
| - Break down materials in contact with brush border.
27
Enterropeptidase
Activates pancreatic trypsinogen.
28
After chyme arrives in duodenum what happens?
Weak peristaltic contractions move it slowly toward jejunum.
29
True or False:
Under control of the CNS control.
- False, not under control of CNS.
30
____________ stimulation accelerates local peristalsis and segmentation.
Parasympathetic
31
Gastroenteric reflex does what?
Stimulates motility and secretion along entire small intestine.
32
Gastroileal reflex triggers what?
Opening of ileocecal valve.
33
What does the gastroileal reflex allow materials to pass from?
Small intestine into large intestine.
34
What are 1 function of hormonal mechanisms?
-Coordinates activities of digestive glands
35
Where are acids neutralized and enzymes are added?
Centered on duodenum
36
Neural mechanisms involving the CNS prepare the ________ _______ for activity, through ____________ innervation.
1. Digestive system
| 2. parasympathetic
37
Inhibit ____________ activity through sympathetic innervation.
gastrointestinal
38
How are movements of materials along the digestive tract coordinated?
Reflexes
39
Motor neuron synapses in digestive tract release ___________.
Neurotransmitters
40
What kind of hormones does the intestinal tract secrete?
peptide hormones
41
What are 6 hormones of the duodenum?
- Gastrin
- Secretion
- gastric inhibitory peptide
- cholecystokinin
- vasoactive intestinal peptide
- enterocrinin
42
What is gastrin secreted by?
G cells
43
What happens when G cells are exposed to incompletely digested proteins? ( 2 activities)
- Promotes increased stomach motility
| - Stimulates production of acids and enzymes.
44
Secretin is released when?
-When chyme arrives in duodenum.
45
What are the 2 functions of secretin when activated?
- Increases secretion of buffers by pancreas and bile by liver
- reduces gastric motility and secretory rates.
46
When is gastric inhibitory peptide secreted?
When fats and carbohydrates enter small intestine.
47
When is cholecystokinin?
Secreted when chyme arrives in duodenum.
48
what affect cholecytokinin have on the body? (2 functions)
- Accelerates pancreatic production and secretion of digestive enzymes.
- Relaxes hepatopancreatic sphinter and contracts gallbladder.
49
What affects does vasoactive intestinal peptide on the digestive system? (3 affects)
- Stimulates secretion of intestinal glands
- dilates regional capillaries
- Inhibits acid production in stomach
50
What 2 effects does enterocrinin have on the body?
- Released when chyme enters the duodenum
| - stimulates alkaline mucus production by submucosal glands.
51
Movements of mucosa increase _________ ________ in the small intestines.
- Absorptive effectiveness
52
What is the large intestine shaped like?
Horseshoe shaped
53
Large intestine extends from end of ilieum to where?
Anus
54
Where is the large intestine in relation to the liver and stomach?
Lies inferior to both body structures.
55
How long is the large intestine?
1.5 meters
56
How wide is the large intestines?
7.5 cm.
57
What are the 3 portions of the large intestine?
- cecum
- colon
- rectum
58
What is the cecum?
- Expanded pouch
- Receives and stores materials arriving from ileum
- Begins compaction
59
Appendix
- Slender, hollow structure about 9 cm. long
- attached to posteromedial surface of cecum
- dominated by lymphoid nodules
- Meso-appendix (smaller mesentery) connects appendix to ileum and cecum.
60
Colon
Larger diameter and thinner wall than small intestine.
61
Haustra
- Pouches in wall of colon
| - Permit expansion and elongation
62
Teniae coli
- Three longitudinal bands of smooth muscle
- Run along outer surfaces of colon, deep to serosa
- Similiar to out layer of muscular layer
- Muscle tone in teniae coli creates haustra
63
Omental appendices
Numerous teardrop shaped sacs of fat in serosa of colon
64
Name the 4 regions of the colon
- Ascending colon
- Transverse colon
- Descending colon
- Sigmoid colon
65
Where does the ascending colon begin?
Superior border of cecum
66
Ascending colon ascending along right lateral and _______ _____ of peritoneal cavity. To the inferior surface the ________.
Bends sharply to the left at ________ ________ _______ (hepatic flexure).
1. posterior wall
2. Liver
3. right colic flexure
67
_________ ______ crosses abdomen from right to left. Turns at left ______ ________ (splenic flexure).
Supported by the ___________ mesocolon. Separated from anterior abdominal wall by greater ________.
1. Transverse colon
2. colic flexure
3. transverse
4. omentum
68
Descending colon proceeds _______ along left side to iliac fossa.
________, firmly attached to abdominal wall.
1. inferiorly
| 2. Retroperitoneal
69
How long is the sigmoid colon?
15 cm.
70
Where is the sigmoid colon in relation to the urinary bladder?
Posterior to it
71
Sigmoid colon empties into what area in the body?
rectum
72
How long is the rectum?
15 cm.
73
What is the function of the rectum?
Expandable organ for temporary storage of feces.
74
Anal canal
- Last portion of rectum
| - Contains small longitudinal folds (anal columns).
75
Anus
- exit of anal canal
| - Keratinized epidermis like skin
76
Internal and sphincter
- Circular muscle layer
- Smooth muscle cells
- Not under voluntary control
77
External anal sphincter
- Encircles distal portion of anal canal.
- Skeletal muscle fibers
- Under voluntary control.
78
What does the large intestine lack?
villi
79
What type of cell does the large intestine have a abundance of?
Goblet cells
80
What are the functions of the large intestines?
- Absorption or reabsorption of water, nutrients, bile salts, organic wastes, and vitamins and toxins produced by bacteria.
- Compaction of intestinal content into feces
- Storage of fecal material prior to defecation.
81
Microbiome
- Microbes (bacteria, fungi, and viruses)that live in and on human body.
- Including those that inhabit large intestine.
82
Vitamins
- Organic molecules
- Important as cofactor or coenzymes in metabolism.
- Normal bacteria in colon make three vitamins that supplement diet.
83
Vitamin K (fat soluble)
Required by liver for synthesizing four clotting factors, including prothrombin.
84
Biotin (water soluble)
Important in glucose metabolism.
85
Vitamin B3 ( pantothenic acid; water soluble)
Required in manufacture of steroid hormones and some neurotransmitters.
86
Organic wastes
Bacteria convert bilirubin to urobilinogens and stercobilingens.
87
What are sometimes absorbed into bloodstream and excreted in urine?
Urobilinogens
88
If urobilinogens and stercobilinogens that remain in the colon are converted into what?
- urobilins
| - stercobilins
89
Bacteria break down peptides into what 2 things?
- feces
| - generate
90
Bateria feed on indigestible carbohydrates and produce?
Fluids (intestinal gas) in large intestine.
91
________ and gastroenteric reflexes move materials in cecum while you _____.
1. Gastroileal
| 2. Eat
92
Movement from _______ to transverse colon is slow, allowing hours of water absorption.
__________ waves move material along length of colon.
Sementation movements mix contents of ______ _______.
1. cecum
2. Peristaltic
3. adjacent haustra
93
Movement from transverse colon through rest of ______ _______. Results form powerful peristaltic contractions called ______ ______.
1. Large intestine
| 2. Mass movements
94
Stimulus is distension of _________ and duodenum. relayed over ______ ______ plexuses.
1. Stomach
| 2. intestinal nerve
95
Distension of ______ _____ initiates defecation reflex.
Involves ____ positive feedback loops.
Both triggered by _________ _______ in the rectum.
1. Rectal wall
2. Two
3. Stretch receptors
96
Intrinsic myenteric defecation reflex
- Short reflex
| - Triggers peristaltic contraction in sigmoid colon and rectum.
97
Parasympathetic defecation reflex
- Long reflex
- Coordinated by sacral parasympathetic neurons
- Stimulates mass movements
98
Elimation of fecese requires relaxtion of internal and external ______ _____.
Reflexes open ________ sphincter.
_________ ________ system much be activated to consciously open external sphincter.
_________ nerves carry somatic motor commands.
1. Anal sphincters
2. internal
3. Somatic nervous
4. Pudendal
99
What 6 nutrients are in a balanced diet?
- Carbohydrates
- Lipids
- Proteins
- Vitamins
- Minerals
- Water
100
________ _______ breaks down physical structure of food.
Digestive system
101
What is food broken down into?
Disassembles component molecules.
102
Molecules released into bloodstream are absorbed by cells and either?
- Broken down to provide energy for ATP.
| - Used to synthesize carbohydrates, proteins and lipids.
103
What does digestive enzymes do?
Break molecular bonds in large organic molecules.
104
Carbohydrates break bonds between what?
Simple sugars
105
What bonds does proteases break?
Amino acids
106
What separates fatty acids from glycerides?
Lipases
107
What are 4 areas that secrete digestive enzymes?
- Salivary glands
- Tongue
- Stomach
- Pancreas
108
Complex carbohydrates are digested 2 steps?
1. Salivary amylase and pancreatic alpha-amylase.
- Carvohydrases from salivary glands and prancreas
2. Brush border enzymes of intestinal microvilli
- Maltase splits bonds between maltose
- Sucrase breaks apart sucrose
- Lactase hydrolyzes lactose
109
Insufficient lactase leads to what?
Lactose introlerance
110
Dipeptidases
In epithelial surface of small intestine, break short peptide chains into individual amino acids.
111
Nucleic acid digestion and absorption
- Nucleic acids are broken down into nucleotides.
- Brush border enzymes digest nucleotides into sugars.
* Absorbed by active transport.
112
Water absorption
- Cells cannot actively absorb or secrete water.
| - Movement of water across digestive tract involves passive water flow down osmotic gradients.
113
Vitamins
Organic compound required in very small quantities.
114
Water-soluble vitamins
Include B vitamins and vitamin C. B12
115
Fat-soluble vitamins
Vitamins A,D, E, and K
116
Gonads
Organs that produce gametes and hormes
117
Testes
- Secrete male sex hormones
| - Produce male gametes-half a billion sperm per day.
118
Ovaries
- Release one immature gamete (oocyte) per month.
- Produce hormones.
- Retains and nurtures zygote.
119
Pathway of sperm
1. Testis
2. Epididymis
3. Ductus deferens
4. Ejaculatory duct
5. Urethra
120
Accessory glands secrete fluid into duct system
- Seminal glands
- Prostate
- Bulbo-urethral glands
121
External genitalia
- Penis
| - Scrotum
122
Testes
-5 cm. long, 3 cm. wide, 2.5 cm thick
-Each weighs 10-15 g
Hang in scrotum
123
Scrotum
- Flesh pouch that encloses testes
- Suspended inferior to perineum
- divided into two chamber by raphe of scrotum
- Each testies lies in a separate scrotal cavity.
124
Spermatic cords
- Extend between abdominpelivic cavity and testes.
- Enclose ducts deferens, blood vessels, nerves, and lymphatic vessels of testes.
- Each begins at entrance to inguinal canal and descend into scrotum.
125
Tunica vaginalis
- Serous membrane
- Lines scrotal cavity
- Reduces friction between opposing surface
* Parietal (outer) layer
* Visceral (inner) layer
126
Dartos muscle
- Layer of smooth muscle in dermis of scrotum
| - Causes characteristic wrinkling of scrotal surface
127
Cremaster
- Layer of skeletal muscle deep to dermis
- Tenses scrotum and pulls testes closer to body
* Due to sexual arousal or decreased temperature.
128
What is temperature for normal sperm development?
1.1 C lower than body temp.
129
Muscles relax or contract to move _____away or toward body.
| Maintains acceptable _______ temperatures.
- Testes
| - Testicular
130
What are the arteries of the testes?
- Deferential artery
- Testicular artery
- Pampiniform plexus
131
Nerves of testes
Branches of genitofemoral nerve form lumbar plexus
132
Inguinal hernias
- Protrusions of visceral tissues into inguinal canal
- Fairly common in males
* Spermatic cord creates weak point in abdominal wall.
133
Tunica alburginea
- Deep to tunica vaginalis
- dense layer of connective tissue rich in collagen fibers
- Continuous with fibers surrounding epididymis
- Fibers form septa testis that converge near entrance to epididymis.
- Supports blood and lymphatic vessels of testis and efferent ductules.
134
Septa subdivide each testis into ______
Lobules
135
Efferent ductules connect where?
Epididymis
136
Interstitial endocrine cells (Leydig cells) produce what?
-Androgens
137
Epididymis
- Start of male reproductive tract.
- Coiled tube almost 7 m long.
- Bound to posterior border
- Head, Body , and Tail
138
Head of epididymis
-Largest part, receives sperm from efferent ductules.
139
Body of Epididymis
On posterior surface of testis
140
Tail of epididymis
- Begins near inferior border of testis
- ascends to connection with ductus deferens
- Primary storage location of sperm.
141
What are the 3 functions of the epididymis?
- Monitor and adjust composition of fluid produced by seminiferous tubes; Sterocillia go up SA for absorption & secretion of fluid in tube.
- Recycle damaged sperm.
- Store and protect sperm and facilitate their functional maturation; 3 weeks.
142
How long are the ductus deferens (vas deferens)
40-45 cm long
143
True or false:
| The ductus deferens is part of the spermatic cord.
- True
144
Where does the ductus deferens start?
-Begins at tail of epididymis and scends through inguinal canal.
145
The ducturs deferens curves inferioly along _______ ______.
| Toward _______ and seminal glands.
1. Urinary bladder
| 2. Prostate
146
Lumen enlarges into what?
ampulla of ductus deferens
147
Ampulla of ductus deferens contains a think layer of what type of muscle?
-Smooth muschle
148
How long is the male urethra?
-18-20 cm
149
What are the 3 regions of the male urethra?
- Prostatic
- Membranous
- Spongy
150
What is the job of the digestive system?
Acquires nutrients from environment which is used to synthesize essential compounds.
151
What is the digestive tract?
What is the digestive tract?
152
What are the 3 accessory organs of the digestive system?
- Teeth
- Tongue
- Various glandular organs
153
When does ingestion occur?
Occurs when food enters oral cavity.
154
What 2 things occur during mechanical digestion and propulsion?
- Crushing and shearing of food.
| - Propelling food along digestive tract.
155
What 5 things are released during secretion?
- Water
- Acids
- enzymes
- buffers
- salts
156
What 3 place do secretions occur?
- Epithelium of digestive tract
- glandular organs
- gallbladder
157
What are 5 things moved during absorption?
- Organic molecules
- Electrolytes
- Vitamins
- minerals
- water
158
Where does absorption take place?
Across digestive epithelium and into interstitial fluid of digestive tract.
159
What is defecation?
Elimination of wastes from body.
160
Compacted dehydrated wastes are call what?
Feces
161
What 3 things does the digestive tract protect us against?
- Corrosive effects of digestive acids and enxymes
- Mechanical stresses
- Bacteria either ingested with food or that reside in digestive tract.
162
Peritoneum is serous membrane lining what cavity?
Peritoneal cavity
163
What does the visceral peritoneum cover?
Organs within peritoneal cavity
164
What does the perietal peritoneum line?
Surfaces of body wall.
165
Serous membrane makes what?
Peritoneal fluid
166
What does peritoneal fluid allow?
Sliding of parietal and visceral surfaces without friction or irritation.
167
Ascites
Abdominal swelling due to buildup of peritoneal fluid.
168
Mesenteries is a double sheet of what?
Peritoneal membrane
169
Where are mesenteries?
Suspend portions of digestive tract with peritoneal cavity.
170
Mesenteries connect what 2 body structures?
parietal peritoneum to visceral peritoneum.
171
What are the 3 functions of the mesenteries?
- Route to and from digestive tract for blood.
- Stabilize positions of attached organs.
- Prevent intestines form becoming entangled.
172
What are the 2 functions of the lesser omentum?
- Stabilizes position of stomach
| - Provides access route for blood vessels and other structures entering or leaving liver.
173
What is the function of the Falciform ligament?
Helps stabilize position of lever relative to diaphragm.
174
Where does the greater omentum extend to?
Extends inferiorly between body wall and anterior surface of small intestine.
175
What are the 4 functions of the Adipose tissue in greater omentum?
- Conforms to shapes of surrounding organs.
- Pads and protects surfaces of abdomen.
- Provides insulation to reduce heat loss.
- stores lipid energy reserves.
176
What is the mesentery proper?
Thick mesenterial sheet.
177
What are 2 functions of mesentery proper?
- Provides stability
| - Permits some independent movement.
178
How far does the mesentery proper extend into the small intestine?
25 cm
179
Mesentery associated with duodenum and pancreas fuse with what?
Abdominal wall
180
During development mesocolon of ascending colon, descending colon, and rectum do what 2 things?
- Fuse to posterior body wall
| - Lock regions in place
181
What are the 4 major layers of the digestive tract innermost to outermost?
- Mucosa (inner most)
- Submucosa
- Muscular layer
- Serosa (outer most)
182
Muscosa
Inner lining of digestive tract.
183
What 3 things does the mucosa contain?
- Epithelium
- Lamina propria
- Muscular muscularis mucosae
184
The oral cavity, pharynx, esophagus and anal canal is made of what type of tissue?
Stratified squamous epithelium
185
The stomach, small intestine, most of large intestine is what type of tissue?
Simple columnar epithelium
186
What is the function of the enteroendocrine cells?
Secrete hormones that coordinate activities of digestive tract and accessory glands.
187
Lamina propria is a layer of areolar tissue that contains what 5 structures?
- Blood vessels
- Sensory nerve endings
- Lymphatic vessels
- Smooth muscle cells
- Scattered lymphatic tissue
188
Smooth muscle cells are arranged in two concentric layers where in the body?
Muscularis mucosae
189
Inner layer of the muscularis mucosae encircles what?
Lumen
190
Outer layer of the muscularis mucosae contains cells arranged parallel to where?
Axis of tract (longitudinal layer)
191
Submucosa contains what 3 things?
- Blood vessels
- lymphatic vessels
- exocrine glands
192
What do the exocrine glands in submucosa secrete?
Buffers and enzymes into digestive tract.
193
What does the submucosal neural plexus do?
Innervates mucosa and submucosa
194
What is the muscular layer of layer of the digestive system involved in?
Mechanical digestion and moving materials along digestive tract.
195
What are movements are coordinated by enteric nervous system? 2 things
Innervated primarily by parasympathetic division
| Also by sympathetic postganglionic fibers.
196
What is the myenteric plexus?
Network of parasympathetic ganglia, sensory neurons, interneurons, and sympathetic postganglionic fibers.
197
What does the serosa cover?
Muscular layer
198
What is Adveitia?
Dense network of collagen fibers that firmly attach the digestive tract to adjacent structures.
199
Rhythmic cycles of activity are controlled by what?
Pacesetter cells that undergo spontaneous depolarization.
200
What is Peristalsis?
Waves of muscular contractions that move a bolus along length of digestive tract.
201
What muscles contract during peristalsis?
- Circular muscles behind the bolus contract
- Longitudinal muscles ahead of bolus contract..
- Wave of contraction in circular muscle.
202
What is Segmentation?
Cycles of contraction that churn and fragment the bolus mixing contents with intestinal secretions.
203
True or False:
Segmentation has a set pattern.
False, segmentation has not set pattern.
204
True or False:
Segmentation does not push materials in any one direction.
True
205
Where is segmentation seen to happen?
Stomach
206
What are the 3 regulation of digestive functions?
- Local factors
- Neural mechanisms
- Hormonal mechanisms
207
Local factors include what 3 things?
pH
Volume
Chemical composition of intestinal contents
208
Stretching of intestinal wall can stimulate what?
Localized contractions
209
Local factors may stimulate release of what 3 chemicals?
- Protaglandins
- Histamine
- Other chemicals that may affect adjacent cells
210
Neural mechanisms control what?
Movement
211
Visceral motor neurons control what?
Smooth muscle contraction and glandular secretion.
212
Short reflexes control what?
Small segments of digestive tract.
213
Long reflexes control what 3 things?
- Provide higher level control
- Stimulate large-scale peristalsis
- Parasympathetic motor fibers synapse in myenteric plexus
214
What are Hormonal mechanisms?
Enteroendocrine cells
215
What do enteroendocrine cells in t the digestive tract do?
Produce peptide hormones
216
Where do enteroendocrine cells travel through to reach target organs?
-Blood Stream
217
What are the 4 functions of the oral cavity?
- Sensory analysis
- Mechanical digestion
- Lubrication
- Limited chemical digestion
218
What structures are used during mechanical digestion in the oral cavity?
- Teeth
- Tongue
- Palatal surfaces
219
What is digested during limited chemical digestion?
- Carbohydrates
| - Lipids
220
What type of tissue is the oral mucosa made of?
Stratified squamous epithelium
221
Where is the oral mucosa located? (3 places)
- Cheeks
- Lips
- Inferior surface of tongue
222
What 2 things are the cheeks supported by?
- Pads of fat
| - Buccinator muscles
223
Where is the oral vestibule?
Between the cheeks & teeth
224
What are gingivae (gums)?
Ridges of oral mucosa
