AMPHIBIA

RANA-TYPE STUDY

Presented by- Dr. Madhurima Sharma

Associate Professor

PG GCG-11

Chandigarh

DIGESTIVE SYSTEM

DIGESTIVE SYSTEM

•ALIMENTARY CANAL

•Mouth

•Buccopharyngeal cavity

•Oesophagus

•Stomach

•Small intestine

•Large intestine (rectum)

•Cloaca

•DIGESTIVE GLANDS

•Gastric glands—gastric juice

•Liver---bile

•Pancreas---pancreatic juice

•Intestinal glands---intestinal juice

1. MOUTH

• Terminal,wide gape;upper jaw

immovable,lower jaw movable

2. BUCCOPHARYNGEAL CAVITY

BUCCAL CAVITY

• Teeth– lower jaw

toothless;homodont;polyphyodont

• Subrostral fossa

• Internal nares

• Bulging of eyeballs

• Tongue

• Pre lingual elevations

PHARYNX

• Glottis

• Openings of eustachian tubes

• OESOPHAGUS--- short ,wide (because of short neck) ,bears longitudinal

folds

• STOMACH---cardiac stomach,pyloric stomach ;cardiac and pyloric

sphincter ; longitudinal folds.

• SMALL INTESTINE--- duodenum,ileum ;hepatopancreatic duct ;

longitudinal folds

• RECTUM --- anus,anal sphincter.

• CLOACA –cloacal aperture

RESPIRATORY SYSTEM

CUTANEOUS RESPIRATION

BUCCOPHARYNGEAL RESPIRATION

PULMONARY RESPIRATION

• Conditions for respiration –

• A membrane permits exchange of gases through it if

• It is thin,moist and semipermeable

• It has abundant blood supply

• It comes in contact with the environment directly or indirectly.

CUTANEOUS RESPIRATION

•Respiratory organ– skin

•Takes place without any effort

•Occurs on land ,in water,during

hibernation

•Skin scaleless

•Epidermis thin

•Mucous glands keep skin moist

•Abundant blood supply

BUCCOPHARYNGEAL RESPIRATION

• Respiratory organ-epithelial lining of buccopharyngeal cavity.

• Lowering of throat-contraction of sternohyal muscles;bph cavity enlarges;reduces pressure of air inside;air rushes inside through external nares,nasal chamber,internal nares.

• Gaseous exchange occurs

• Raising of throat by petrohyal muscles—reduces bph cavity;raises air pressure inside;foul air expelled through nares.

• In this respiration,external nares remain open,mouth and glottis remain closed,lungs reman idle.

PULMONARY RESPIRATION

•Site of respiration– lungs;alveoli

•Throat is lowered by contraction of

sternohyal muscles.

•ASPIRATION– air rushes into

buccopharyngeal cavity

•Throat raised by petrohyal

muscles;mouth external nares and

oesophagus closed,air forcss glottis to

open enters lungs through

laryngotracheal chamber.

•air passes from bph cavity into lungs--

INSPIRATION

•Gaseous exchange takes place

•EXPIRATION-throat lowered;partial

vaccum in bph cavity;glottis opens;air

rushes out from lungs into bph

cavity;throat raised again ;fowl air

expelled out.

CIRCULATORY SYSTEM

• BLOOD VASCULAR SYSTEM HEART

BLOOD VESSELS—arteries and veins

Arterial system

Venous system

BLOOD

• LYMPHATIC SYSTEM

TISSUE FLUID

LYMPH CHANNELS

LYMPH HEARTS

HEART

• Protective covering—two layered

•Parietal pericardium

•Visceral pericardium

•Pericardial cavity filled with pericardial

fluid

•Chambers—five

•;Sinus venosus,

•Rt.auricle

• Lt auricle

•,Ventricle

•,Truncus arteriosus

• SINUS VENOSUS-triangular ;located on dorsal side of heart ; recieves iarge vena cava at each of its three angles.

• AURICLES– thin walled ;separated by auricular septum ;sinus venosus communicates with Rt auricle through sinu-auricular aperture bearing 2 lip like,flap like sinu-auricular valves.

Lt auricle has a small unguarded aperture into which opens the common pulmonary vein.

• Auricles open into ventricles through auriculo ventricular aperture guarded by 4 flap like auriculo-ventricular valves.Free edges of the valves connected to inner surface of ventricle by CHORDAE TENDINEAE who check the valve from being pushed into the auicles.Valves open towards ventricles only

• VENTRICLE is triangular;has thick muscular walls;baers on its inner surface ridges and depressions called COLUMNAE CARNEAE and FISSURES respectively.

• TRUNCHUS ARTERIOSUS—tubular chamber lying obliquely on ventral surface of Rt auricle;Bifurcates near anterior end of heart into 2 branches– each with 3 AORTIC ARCHES;CAROTID,SYSTEMIC and PULMOCUTANEOUS.

.

ARTERIAL SYSTEM

CAROTID ARCHES

• External carotids

• Internal carotids:-Opthalmic

Cerebral

Palatine arteries

SYSTEMIC ARCHES

• Oesophageo-occipitovertebral art:-

Oesophageal art

Occipito-vertebral art

• Sub clavian artery

• Coeliaco mesenteric artery:-

Coeliac art

Anterior mesenteric art

• Renal arteries

• Lumbar arteries

• Posterior mesenteric artery

• Iliac arteries:-

Epigastrico-recto-vescicular art

Femoral art

Sciatic art

PULMOCUTANEOUS ARCHES

•Pulmonary art

•Cutaneous art

VENOUS SYSTEM •VENAE CAVEA:-

PRECAVAL

External jugular vein

Innominate vein

Subclavian vein

POSTCAVAL

Renal veins

Genital veins

Hepatic veins

•VEINS FROM HIND LIMBS:-

Femoral vein

Sciatic vein

Dorsolumber vein

Oviducal vein

Anterior abdominal vein

Vesicular vein

•VEINS FROM ALIMENTARY

CANAL:-

Oesophageal vein

Gastric vein

Duodenopancreatic vein

Intestinal vein

Splenic

Posterior mesenteric

• PULMONARY VEINS:- Common pulmonary vein

• PORTAL VEINS AND PORTAL SYSTEMS:-

RENAL PORTAL SYSTEM

Renal portal vein—sciatic

femoral

dorso-lumbar

Oviducal vein

HEPATIC PORTAL SYSTEM Anterior abdominal vein—pelvic veins

vesicular veins

Hepatic portal vein—oesophageal

gastric

duodenopancreatic

intestinal

splenic ;rectal

anterior abdominal

SINUS VENOSUS RIGHT AURICLE

HEAD SKIN

TRUNK LUNGS LEFT AURIICLE

AND

LIMBS

TRUNCUS ARTERIOSUS VENTRICLE

BLOOD

• PLASMA

• CORPUSCLES

RBCs

WBCs:-

Non-granular leucocytes

Granular leucocytes:-basophils

neutrophils

eosinophil

• SPINDLE CELLS

LYMPHATIC SYSTEM

• TISSUE FLUID

• LYMPH CHANNELS

Sub-cutaneous lymph sinus

Sub-vertebral sinus

• LYMPH HEARTS

2 pairs

NERVOUS SYSTEM

• CENTRAL NERVOUS SYSTEM

BRAIN

SPINAL CHORD

• PERIPHERAL NERVOUS SYSTEM

CRANIAL NERVES

SPINAL NERVES

• SYMPATHETIC NERVOUS SYSTEM

• PARASYMPATHETIC SYSTEM

NERVOUS SYSTEM

BRAIN

• FORE BRAIN

Olfactory lobes

Cerebral hemispheres

Diencephalon

• MID BRAIN

Optic lobes

Crura cerebri

• HIND BRAIN

Cerebellum

Medulla oblongata

• Rt and Lt sides of brain connected by transverse bands of nerve fibres called COMMISSURES.There are 3 commissures—Anterior,Dorsal and Posterior.

• All cavities of brain are continous and filled with CEREBRO-SPINAL FLUID.It is secreted by anterior and posterior choroid plexus.

• Brain consists of two types of nervous tissue—GREY MATTER(nerve cells) and WHITE MATTER(nerve fibres).

• Brain is surrounded by two protective membranes called MENINGES- DURAMATER is the outer thick and tough menix while PIA-ARACHNOID MEMBRANE is the thin and vascular membrane in close contact wih the brain.

• Space between dura mater and pia arachnoid membrane is SUB DURAL

SPACE.The space between sub dural space and bony wall of cranial cavity is EPIDURAL SPACE.These are filled with cerebro-spinal fluid who acts as a cushion,absorbs shocks and nourishment.

The frog has a highly developed nervous system which

consists of a brain, spinal cord and nerves.

The of a frog is much smaller than that of a human.

Frogs have ten cranial nerves (nerves which pass information

from the outside directly to the brain) and ten pairs of spinal

nerves (nerves which pass information from extremities to

the brain through the spinal cord).

By contrast, all amniotes (mammals, birds and reptiles) have

twelve cranial nerves.

Frogs do not have external ears; the eardrums (tympanic

membranes) are directly exposed, the ear contains

semicircular canals which help control balance and

orientation.

FOREBRAIN

CEREBRUM -Enclose a cavity, known as lateral ventri

cle/ Paracoel which communicates with

Rhinocoel in front & diacoel behind

Through foramen of monro

-Roof known as corpora straita

OLFACTORY LOBES

Ant. Most part of the brain olfactory nerves,

coming from nares, reach this region.

They have a cavity called rhinocoel.

DIENCEPHALON Encloses a cavity called diacoel. Pineal stalk

above, Infundibulum & hypophysis below, floor

is thick. Saccus vasculosa acts as pressure

receptor.

MID BRAIN: it forms the middle portion of the brain &

consists of two parts i.e. optic lobes & crura cerebri.

Optic lobes: they are a pair of prominent oval bodies, a

diencephalon with the medulla oblongata.

HIND BRAIN: it forms the posterior part of the brain &

consists of two regions cerebellum & medulla

oblongata.

Cerebellum: it is very small, narrow, band placed on the

dorsal side behind the optic lobes. It contains a small

cavity, the cerebellar ventricle.

Medulla oblongata: it is the hindermost part of the brain.

Enclose a cavity, the myelocoel. The myelocoel

communicates with the iter in front & the central canal

of the spinal cord behind. It sends into the fourth

ventricle finger like proceses, the posterior choroid

plexus.

PERIPHERAL NERVOUS SYSTEM:

1.Cranial nerves- pass information from outside directly to the

brain. They are ten in number i.e. Olfactory, optic,

occulomotor, pathetic/ trochlear, trigeminal, abduscens, facial,

auditory, glossopharyngeal, vagus.

2. Spinal nerves- pass information from extremities to the

brain through the spinal cord. There are 10 pairs of cranial

nerves.

AUTONOMIC NERVOUS SYSTEM:

1.Sympathetic nervous system includes a pair of long, delicate

cords termed the sympathetic cords. Each sympathetic cord is

connected with each of the spinal nerves of its side by a

ramus communicans.

2.Parasympathetic nervous system consists of small groups of

nerve cells in the wall of the viscera, these are called as the

parasympathetic ganglia.

SPINAL CORD •Widens in front to merge with

medulla oblongata of brain and

tapers posteriorly to form filum

terminale in the urostyle

•Slightly flatteed dorso-ventrally

•Shallow dorsal fissure

•Deep longitudinal ventral fissure

•Thin fibrous partition-dorsal

septum

•Rt and Lt halves asymmetrical.

•Central canal lined by single

layered columunar epthelium-

ependyma

•Central canal closed posteriorly

but opens in front into fourh

ventrical of brain ; filled with

cerebro spinal fluid.

CRANIAL NERVES • Ten pairs

• OLFACTORY

• OPTIC

• OCULOMOTOR

• PATHETIC or TROCHLEAR

• TRIGEMINAL

opthalmic

maxillary

mandibular

• ABDUCENT

• FACIAL

palatine

hyomandibular

• GLOSSOPHARYNGEAL

• VAGUS

laryngeal

cardiac

gastric

pulmonary

SPINAL NERVES •9 or 10 pairs of spinal nerves

similar in origin and distribution

•Arise from spinal cord by two

roots-DORSAL AND VENTRAL

•Sensory root:-dorsal horn of

grey matter,dorsal root

ganglion,spinal cord.

•Motor root:-ventral horn of

grey matter,muscles

•Inter-vertebral foramen

•Each spinal nerve divides into

three branches:-RAMUS

DORSALIS,RAMUS

VENTRALIS,RAMUS

COMMUNICANS

Spinal Nerve I

The most anterior spinal nerve, leaves the vertical column,

bends posteriorly then anteriorly. In the frog, it will go the

chin region.

Spinal Nerve II The brachial nerve, running to the arm

Spinal Nerve III

Forms a connection with I and II before it passes laterally

to the body wall. Where the three join, they form the

brachial plexus.

Spinal Nerves IV,

V and VI Small delicate nerves to the abdominal wall

Spinal Nerves VII,

VIII and IX

Unite to form a complicated sciatic plexus which results in

the sciatic nerve to the hind leg

Spinal Nerve X very small nerve to the pelvic region. It may also

contribute fibers to the sciatic plexus.

SYMPATHETIC NERVOUS SYSTEM

• Sympathetic cords are a pair of long delicate cords beneath the vertebral column , one on either side of the dorsal aorta.;continue forward outside systemic arches.They reach the head,enter cranium along with 9th and 10th cerebral nerves and enters the Gasserian ganglion.

• Each trunk bears a series of10 sympathetic ganglia which are connected to the adjacent spinal nerves by small nerves called ramus communicans.

• Corresponding ganglia of both the sympathetic cords are also connected together by small transverse commisures.

• Sympathetic ganglia give branches to visceral organs:-heart,stomach,intestine,liver,pancreas,kidneys,urinary bladder,gonads,blood vessels etc.

• Also controls visceral functions like heartbeat,bloodpressure,blood circulation,digestion,absorption, excretion,gametogenesis etc.

PARA SYMPATHETIC NERVOUS SYSTEM

• Made of parasympathetic ganglia present in the wall of

the same visceral organs which are supplied by

sympathetic ganglia.

• Each parasympathetic ganglion is a group of neurons.

• These are connected to the CNS through long sized pre-

ganglionic parasympathetic nerve fibres running in some

cranial and spinal nerves while these ganglia give small

sizedpost-ganglionic parasympathetic nerve fibres to

visceral organs.

SENSE ORGANS

• PHOTO RECEPTORS or EYES

• STATOCOUSTIC RECEPTORS or EARS or ORGANS

OF HEARING AND EQUILIBRIUM

• TANGORECEPTORS or ORGANS OF TOUCH

• OLFACTORECEPTORS or ORGANS OF SMELL

• GUSTATORECEPTORS or ORGANS OF TASTE

EYE

• Eyes located in cavities called orbits

• Composed of three layers

outer fibrous coat:- cornea,sclerotic

middle vascular coat or uvea:-choroid,ciliary,irridial

inner nervous coat or retina:-optical,ciliary part

• Eye balls are moved in the orbit by 6 muscles who are

arranged in two groups:-

oblique-inferior and superioroblique

rectus- internal,external,superior and inferior rectus

• Eye is protected by upper and lower eye lids and the

nictitating membrane.

• Eye has two glands:-LACRYMAL and HARDERIAN GLAND.

.

• Ear has two parts:-MIDDLE EAR ,INTERNAL EAR

• MIDDLE EAR:-TYMPANUM ,EUSTACHIAN TUBE,COLUMELLA,

STAPES.

• INNER EAR:-VESTIBULE (utriculus,sacculus)

SEMI CIRCULAR DUCTS

• Organ of HEARING, EQUILIBRIUM and VELOCITY

EAR

EXCRETORY SYSTEM

•KIDNEYS:- mesonephros in adult and

pronephros in tadpole.

•NEPHRON is the smallest unit of

structure and function.

•URETERS:- slender transparent ducts

who also function as URINOGENITAL

DUCTS.

•URINARY BLADDER:-thin

walled,transparent,bilobed, highly

distensible sac.it opens into the cloaca.

•CLOACA:-is a small median chamber

which serves as a common passage for

faeces,gametes and urine.

•Kidneys produce urine by

ULTRAFILTRATION<TUBULAR

REABSORPTION ANDTUBULAR

SECRETION.

FEMALE REPRODUCTIVE SYSTEM

•OVARIES

•OVIDUCTS

ovarian funnel

ovarian tube

•OVISAC

•CLOACA

•Breeding season extends from july-

september.when ovaries produce ova and

the abdomen swells due to these eggs.

•Ripe eggs are shed into the body cavity by

rupturing of ovaries.

•The ova float in the coelomic fluid and are

driven into the oviduct through their funnel.

•While passing through oviducts eggs are

coated with gelatinous albumen secreted by

gland cells of the oviduct.

•Eggs are stored in ovisacs temporarily and

laid in water through cloaca and cloacal

aperture.

MALE REPRODUCTIVE SYSTEM

• Testes

• Presence of bidders canal inside the kidney

• Ureters act as urinogenital ducts and are functional mesonephric or

wolffian ducts.no sertoli cells in seminiferous tubules of testes.

• Sperms shed into water through cloacal aperture.

AMPLEXUS

• Breeding in quiet, shallow

waters.

• Male attracts the female

by croaking loudly.

• Female recogonized due

to swollen belly.

•In water ,the coating of gelatinous albumen covering the egg swells up into

a jelly like substance and the eggs adhere into a masscalled spawn.

•The jelly protects the eggs from mechanical injury,fungus and aquatic

insects.

•Large number of eggs are laid but only few develop into adults as casuality

is enormous.

SPAWN OF FROG

LIFE HISTORY OF FROG