Organ Systems of the Toad

Digestive System

• Function of nutrition (ingestion, digestion, absorption and egestion)

• Both physical and mechanical breakdown of food

• Amoeba and Paramecium – formation of a food vacuole

Incomplete Digestive System

• Mouth serves as entrance of food and exit of waste materials

• Chlonorchis and Fasciola – trematodes; with 2 suckers for attachment to host

Cockroach Digestive System

• Esophagus

• Crop

• Gizzard

• Intestinal caeca

• Midgut

• Mapighian tubules

• Hindgut

Complete Digestive System

• Coelom -> pericardial cavity and pleuro-peritoneal cavity

• Pleuro-peritoneal cavity– Body wall lining: parietal peritoneum

– Viscera lining: visceral peritoneum

• Mesenteries – suspend the viscera from the body wallo Mesogaster – suspends stomach

o Mesorecturm – suspends large intestine (rectum)

o Mesenterium – suspends small intestine (ileum)

• Omentum – connect viscera

o Gastro-hepato-duodenal omentum – connects the stomach, liver, duodenum

Buccal Cavity

• Maxillary teeth

• Tongue

• Esophageal opening

• Glottis

• Opening to vocal sacs (males only)

• Choanae/internal nares

• Vomerine teeth

• Opening to Eustachian tube

Digestive Tube

• Esophagus

• Stomach

• Pyloric sphincter

• Small intestine

– Duodenum

– Ileum

• Large intestine

• Cloaca

Digestive Glands

• Liver – Largest gland in the body

– Secretes bile

• Gall bladder– Stores bile

– Drained by cystic duct

• Pancreas– Within gastro-hepato-duodenal omentum

– Secretes pancreatic juice

• Common bile duct – union of cystic duct, hepatic ducts, pancreatic ducts

Respiratory System

• Facilitates the exchange of gases between the organism and its environment

• Derived from the integument of the lining of the digestive tube

• Permeable, highly vascularized, in contact with medium rich in oxygen

Aquatic Respiratory Systems

• Gills

• Gill arches

• Pharyngeal clefts

Terrestrial Respiratory Systems

• Tracheal system – provide oxygen directly to tissues

• Tracheal trunk

• Spiracles - openings

Excretory System

• Excretion of waste substances

• Protonephridia – lower metazoans

• Metanephridia – annelids

• Nephridia – mollusks

• Green glands – crustaceans

• Malpighian tubules – insects, arachnids (uric acid crystals)

• Kidneys - vertebrates

Kidneys

• Retroperitoneal

• Lie in cisterna magna

• Drained by mesonephric/Wolffian duct (toads) or ureter (mammals)

• Drains into urinary bladder which stores urine before releasing it into the cloaca

Mammalian Kidney

• Cortex– Renal corpuscles

– tubules

• Medulla– Collecting tubules

• Renal pelvis• Expanded beginning of ureter

• Hilus• Concavity containing the

blood vessels (renal artery and vein)

*renal pyramid – made up of collecting tubules and renal papilla

Circulatory System

• Transport of gases, nutrients, metabolic wastes, hormones and other substances to the different parts of the body

• Assists in homeostasis

• Not present in lower metazoans

Open Circulatory System

• Aorta

• Heart– With lateral ostia guarded by

valves to prevent backflow

– Located in the pericardial sinus

– Ventral wall is called the dorsal diaphragm

• Trachea (respiratory system)

Closed Circulatory System

CONUS ARTERIOSUS

Arterial System

COELIACOMESENTERIC ARTERY

COELIAC ARTERY

PULMOCUTANEOUS ARTERY

Venous System

ANTERIOR VENA CAVA

POSTERIOR VENA CAVA

Mammalian Heart

Nervous System• Perceive and transmit stimuli, coordinate and integrate

the functions of the different organ systems

1. Nerve Net – coelenterates

– Impulses transmitted in all directions from the point of stimulations

2. Ladder – flatworms

– Cephalization present

3. Ganglionic – arthropods & mollusks

– Ventral nerve cord and cerebral ganglia

4. Tubular – vertebrates

–Hollow nerve tube

Types of Nervous Systems

Frog Brain

Cerebellum

Diencephalon

Frog Brain Vesicles

• 1st and 2nd lateral vesicles

• 3rd ventricle

• Opticoels

• Aqueduct of Sylvius

• 4th Ventricle

Huling hirit• Importante ang blood tracing, sabihin ang lahat ng

vessels na dinadaanan ng dugo pag pinatrace kayo. Alam niyo na dapat kung ano yung nagsusupply o nagdedrain ng mga parte ng katawan ng toad.

• Kung napansin niyo, ito lang rin yung nasa manual, kaya magbasa kayo ng manual ok? Andun naman halos lahat ng sagot, maliban sa answers to questions nadapat sinagutan niyo na.

• Hindi ko sinama yung sa nervous system masyado, ipapasa niyo pa kasi sa akin yun sa exam date.

• Sa exam mismo, basahin niyo ng mabuti yungquestions.

• Good luck sa inyong lahat! See you in Bio 12.