LBYZOOL Activity 10-14 (Lab Exam 4)

The Digestive System, The Respiratory System, The Circulatory System, The Urogenital System, & The Nervous System

Digestive System

functions of organ system:

- ingestion of food
- physical and chemical digestion of food
- absorption of nutrient molecules
- elimination of undigested remains

ingestion, digestion, absorption, and elimination

4 functions of digestive system

physical & chemical digestions

types of digestion

digestive tract & digestive glands

parts of digestive system

alimentary canal

aka digestive tract

mouth & cloaca

openings of alimentary canal

mouth, buccal cavity, pharynx, esophagus, stomach, small intestine, large intestine, rectum, & cloaca

parts of digestive tract

liver, gallbladder, & pancreas

accessory glands of digestive system

hepatic lobules, central vein, hepatic cells, & hepatic sinusoids

histology of liver

hepatic lobules

histology of liver:

- separated by connective tissue partition
- can observe portal canals

septa

histology of liver:

connective tissue partition that separates hepatic lobules

portal veins, hepatic arteries, & bile duct

histology of liver:

portal canals

central vein

histology of liver:

- at the center of the lobule
- arrow 1

hepatocytes

histology of liver:

- hepatic cells
- radiating from the central vein and polygonal shape
- arrow 2

hepatic sinusoids

histology of liver:

- spaces in between hepatic plates
- arrow 3

exocrine & endocrine

2 functions of pancreas

exocrine pancreas

histology of pancreas:

- pancreas that perform the digestive function
- contain acini

acini

histology of pancreas:

- consists of pyramidal-shaped cells surrounding a lumen
- arranged into small lobules
- secrete enzymes
- arrow 1

endocrine pancreas

histology of pancreas:

- pancreas that contain iolated pancreatic islet
- secrete hormones

islets of langerhans

histology of pancreas:

- pale-staining structures composed of cells arranged in cords
- have rich capillary network
- secretion will go to blood stream to the body parts
- arrow 2
- has 2 types of cells

iolated pancreatic islet

aka islets of langerhans

alpha & beta cells

2 types of cells in islets of langerhans

alpha cell

cell in pancreas that secrete glucagon

beta cell

cell in pancreas that secrete insulin

upper and lower lip folds, sulcus marginalis, maxillary teeth, vomerine teeth, eustachian tube, glottis, esophagus, tongue, vocal sacs, eyeball prominences, internal nares, & tuberculum prelinguale

parts of buccal cavity

upper and lower lip folds

part of buccal cavity:

- skin folds in the margin of the upper jaw and lower jaw
- arrow 2 & 6

median subrostral fossa

part of buccal cavity:

- prominent depression at the tip of the upper jaw
- arrow 1

sulcus marginalis

part of buccal cavity:

- pair of deep grooves found at the inner margin of the upper jaw
- receives elevation at the lower jaw

maxillary teeth

part of buccal cavity:

- row of small teeth along the margin
- around the upper edge of the jaw

vomerine teeth

part of buccal cavity:

- used to hold the prey and keep it in place until they can get a good grip on it and squash their eyeballs down to swallow their meal
- set of teeth found on the roof of the mouth

eustachian tube

part of buccal cavity:

- pair of openings in the mouth
- tube connects the mouth cavity with the cavities of the middle ear (tympanum)
- posterolateral side of the eyeballs, medial to the angles of the jaw
- equalize air pressure
- arrow 4

glottis

part of buccal cavity:

- opening at back of mouth leads to lungs
- ventral to the esophagus
- laryngeal prominence with a vertical slit-like opening
- gas exchange

esophagus

part of buccal cavity:

tube that connects the mouth to the stomach

tongue

part of buccal cavity:

- attached at front of mouth near anterior end by a short pedicle
- extends to catch insects
- arrow 5

pedicle

part of buccal cavity:

attached tongue to mouth

vocal sacs

part of buccal cavity:

- 2 slit-like openings
- posterolateral corner of the floor of the tongue
- often lacking in the females

eyeball prominences

part of buccal cavity:

- bulging regions at the posterior half of the roof of mouth
- arrow 3

internal nares

part of buccal cavity:

- on top of mouth
- anterolateral openings
- allow gases in and out

tuberculum prelinguale

part of buccal cavity:

- located at tip of lower jaw
- median elevation at the tip of lower jaw
- arrow 7

Frog Dissection for digestive system

- ventral side
- cut from cloaca to lower jaw
- "I cut"

anterior or ventral abdominal vein

- very large vein to the left of the linea alba
- connects to hepatic portal vein
- blue line

ovaries filled with eggs

female frog if you see their ___

pericardial cavity & pleuroperitoneal cavity

cavities in the toad once opened

pericardial cavity

anterior cavity containing the heart

pleuroperitoneal cavity

posterior cavity housing the lungs and other internal organs & viscera

transverse septum

separates pericardial & pleuroperitoneal cavities

parietal peritoneum

glistening membrane in the inner side of the muscular body wall

visceral peritoneum

extension of parietal peritoneum that forms the covering layer of intestine & other viscera

serosa

aka visceral peritoneum

mesentery

- suspends digestive tract
- extensions of parietal peritoneum
- 2 parts

dorsal & ventral mesentery

2 parts of mesentery

dorsal mesentery

mesentery:

- attaches the digestive tract to the medial dorsal line
- has 2 types

mesentery proper & mesorectum

2 types of dorsal mesentery

mesentery proper

mesentery that supports small intestine

mesorectum

mesentery that supports large intestine

ventral mesentery

mesentery:

- attaches the organs to the midventral line
- lost except in region of liver and urinary bladder

liver

- large trilobed brownish organ occupying anterior half of pleuroperitoneal cavity
- secretes bile and processes digestive food molecules
- arrow 1

bile

fluid produced by liver that aids in digestion of fats

gall bladder

- greenish spherical sac that stores bile
- found between left and middle liver lobes
- arrow 2

common bile duct

- hepatic ducts from the liver and cystic ducts from the gallbladder join
- enters the duodenum of the small intestine
- lined by simple columnar epithelium

stomach

- stores food and mixes it with enzymes to begin digestion
- found behind liver
- contains rugae
- 3 regions
- arrow 4

cardiac region, fundus, & pyloric region

3 regions of the stomach

cardiac region

region of the stomach nearest to the esophagus

cardiac sphincter

sphincter that guards cardiac region

fundus

region of the stomach that bulges anteriorly

pylorus

region of the stomach closest to the small intestine

pyloric sphincter

sphincter that guards pyloric region

rugae

longitudinal folds in the inner wall of the stomach

mesogaster

- portion of dorsal mesentery that supports the stomach
- arrow 3

small intestine

- digests and absorb digested food
- found below pylorus
- arrow 5

duodenum

short, straight, anterior-most segment of the small intestine

pancreas

- yellowish gland found between pylorus & duodenum
- provides digestive enzymes and bicarbonates that are secreted into the small intestine

ileum

part of small intestine that proceeds posteriorly as coiled structure

large intestine

- stores undigested food
- found below small intestine

cloaca

- chamber that serves as a common passageway to the outside for both digestive and urogenital systems
- terminates at the cloacal aperture
- anterior to the entry of the mesonephric duct

spleen

- organ in circulatory system
- NO digestive function
- round dense body
- makes, stores, and destroys blood cells
- found behind small and large intestines

Respiration

- exchange of gases
- has 2 stages

ATP

result of oxygen obtained from the environment needed for metabolism

CO2

by-product of metabolism released to the environment

external respiration & internal respiration

2 stages of respiration

external respiration

exchange of gases between the environment and the respiratory organs

internal respiration

exchange of gases between body fluids and tissue cells

nostrils, nasal cavity, pharynx, larynx, trachea, bronchus, bronchioles, alveoli, & blood

flow of respiration

skin, lungs, & mucous lining of mouth

- 3 surfaces of the frog used to exchange gas with the surroundings
- characterized by semi-permeable membrane

skin

- composed of thin membranous tissue
- permeable to water
- contains a large network of blood vessels
- contains mucous glands

mucous glands

glands in the skin that keep the frog moist, which help absorb dissolved oxygen from the air

nostrils

- pair of openings at the anterolateral part of the snout
- aka external nares
- opening lead into the internal nares

larynx

- voice box
- supported or stiffed by cartilages
- has vocal cords in each half

arytenoid cartilages

anterior pair of cartilages that support larynx

cricoid cartilages

posterior pair of cartilages that support larynx

vocal cords

thin elastic bands in each halves of the larynx

bronchus

- extremely short tube connected to the lungs
- quite difficult to locate

lungs

- collapsed or egg-shape
- membranous sacs
- lined by alveoli
- red arrow

collapsed

lung shape of preserved toad

egg-shaped

lung shape of living toad

alveoli

- numerous chambers of the lungs that sometimes interconnect with one another
- small air pockets
- where gas exchange takes place
- connected to blood vessels
- arrow 1

interalveolar septum

- very thin partition between alveoli
- arrow 2

bronchiole

- branches from bronchus to alveoli
- part A

Circulatory System

functions of organ system:

- transport of respiratory gases, food materials, waste products, hormones, and minerals within the body
- defense against foreign organisms
- maintenance of body temperature in warm-blooded or homeothermic animals

Open & Closed Circulatory System

2 Types of Circulatory System