Respiratory System

Respiration

Classified into:1.External respiration2.Internal respiration

the diffusion of gases across moist linings of the mouth and the pharynx

accounts 1-7% of the total gas exchange

Pulmonary ventilation occurs by the buccal pump mechanism

muscles of the mouth and pharynx create a positive pressure to force air into the lungs

called Integumentary Respiration

Skin has the simplest structure of all the major vertebrate respiratory organs

Facilitated by a uniform capillary network lies in a plane directly beneath the epidermis

Gives 25% of oxygen

Aided by the mucous layer

consists of stratified epidermis and dermis

contains mucous, poison and serous glands

keeps the skin of amphibians moist

protects the skin against injuries

Facilitates gas exchange through the skin

Makes body slimy as defense mechanism

tuck legs

seek shelter

put themselves in wet surfaces

burrow themselves

simply breathing

the exchange of gases between the lungs and the air

Air passages1.External nares or nostril2.Nasal cavities3.Internal nares4.Mouth or buccal cavity

5. Glottis

made up of a main framework of cartilage plates joined together by a dense connective tissue

Trachea

Histology of the trachea

Tunica mucosa – pseudostratified columnar epithelium

Tunica or lamina propria- elastic fibers

Tunica submucosa- layer of collagenous and elastic fiber

Hyaline cartilage- C or Y shapedTracheal muscle- smooth muscleTunica adventitia- CT surrounding

the trachea

• Lung

HISTOLOGY OF THE LUNGS

• Peritoneal membrane- plura• Alveoli- capillary network• Interalveolar septa –Elastic Ct

w/ B.V and L.V

Air sacs of lung tissue

Nuclei of squamous epithelial cells

Inter-alveolar septum

Urogenital

Urogenital System

• Consists of excretory and reproductive system• In frog, the skin, the lungs, the liver and the

kidney ---- major excretory organ

Histology of the kidney

• Flattened bean– hilus (medial)

• Tunica fibrosa- Renal capsule (dense collagenous bundles)

• Tunica adiposa

kidney

Histology of the kidney

Divided into:• Cortex • medulla

Structure of the Nephrons

Made up of:• Malphigian body• Uriniferous tubule– Secretory tubules– Excretory/ collecting

tubules

Histology of the Urinary bladder

• Tunica mucosa– Transitional epithelium• Tunica submucosa- Connective tissue and blood vessel• Tunica muscularis–Smooth muscle• Tunica adventitia- Loosely arranged tissue-Covered externally by peritoneum

Tunica muscularisSmooth muscle

Tunica submucosa

Tunica mucosa

Reproductive System

Reproductive

Ovaries-ventral to the kidney-mesovarium-visceral peritoneum

(covering)-egg lies in follicles

Reproductive

Oviducts/Mullerian ducts-whitish convuluted tubes (sides of the body)-extend anteriorly to the lungs

Oviduct-opens anteriorly into the

coelom– ostium-ostium dilates to form the

ovisac or uterus

Oviducts/Mullerian ducts

ovary Ostium of the oviduct

Ovisac/ uterusOviduct proper

cloacaanus

Male reproductive• Testes– Surrounded by visceral

peritoneum– Attached by mesorchium

• Vasa efferentia• Slender tubule that passes

through the mesorchium to the longitudinal canal and then the collecting tubules of the kidney

testis

• Vasa deferentia /wolffian duct– Refers to the ureters– dilate to form seminal

vesicle

testis Vasa efferentia

cloacaSeminal vesicle

anus

• Vestigial oviducts– Wavy whitish tubules

lying besides the ureters• Corpora adiposa

Corpora adiposa