Organ Systems in Organ Systems in Other AnimalsOther Animals

Cow, Fish, Frog, Crayfish Cow, Fish, Frog, Crayfish

GoalsGoals

To become aware of the diversity To become aware of the diversity that is present in members of the that is present in members of the animal kingdom.animal kingdom.

To compare the organ systems of To compare the organ systems of humans to other animals.humans to other animals.

Digestive System - CowDigestive System - Cow

Cows are large mammals that mainly Cows are large mammals that mainly eat grass and plant material.eat grass and plant material.

Plant matter contains Plant matter contains cellulosecellulose, , which is very hard to break down.which is very hard to break down.

Four Stomachs?Four Stomachs?

Much chewing is needed to break Much chewing is needed to break down plant fibres.down plant fibres.

Four stomach chambers are needed Four stomach chambers are needed to completely digest the tough plant to completely digest the tough plant cellulose.cellulose.

Four Stomachs?Four Stomachs? RumenRumen

The largest chamberThe largest chamber Digests cellulose with the assistance of Digests cellulose with the assistance of

bacteria.bacteria. ReticulumReticulum – a secondary chamber that – a secondary chamber that

digests non-plant materialdigests non-plant material OmasumOmasum – absorbs water back into the – absorbs water back into the

body.body. AbomasumAbomasum

the “true stomach”the “true stomach” Digests proteins, fats, and sugars, much like Digests proteins, fats, and sugars, much like

a human stomach.a human stomach.

In HumansIn Humans

Human have only one stomach Human have only one stomach chamber.chamber.

We cannot digest We cannot digest cellulosecellulose.. It is thought that the appendix was It is thought that the appendix was

once a secondary stomach for once a secondary stomach for digesting cellulose.digesting cellulose.

Respiratory System - FishRespiratory System - Fish

Fish live under water, and do not Fish live under water, and do not breathe “air”breathe “air”

GillsGills are required to absorb are required to absorb dissolved oxygen directly from the dissolved oxygen directly from the water.water.

Breathing WaterBreathing Water

GillsGills – network of – network of fanned fanned membranesmembranes with many blood vessels. with many blood vessels.

OO22 is absorbed and exchanged for is absorbed and exchanged for COCO22, much like in human lungs., much like in human lungs.

Why are gills fanned out?

The OperculumThe Operculum

Most fish have an Most fish have an operculumoperculum, or , or ‘cheek’ to pump water through their ‘cheek’ to pump water through their gills.gills.

OperculumSharks do not, and must always be moving to keep water flowing across their gills.

Reproductive System - Reproductive System - FrogFrog

Frogs are amphibians, which means:Frogs are amphibians, which means: They They mustmust live part half of their life in live part half of their life in

water.water. Lay soft eggs outside of the body.Lay soft eggs outside of the body.

Laying EggsLaying Eggs

Frogs lay gelatinous strands of eggs Frogs lay gelatinous strands of eggs in the water which hatch into in the water which hatch into tadpolestadpoles..

Tadpoles have gills which require Tadpoles have gills which require them to stay in the water.them to stay in the water.

MetamorphosisMetamorphosis

As frogs grow, they lose their gills As frogs grow, they lose their gills and grow lungs and limbs.and grow lungs and limbs. This allows them to live on land.This allows them to live on land.

HumansHumans

Baby humans are born functionally Baby humans are born functionally the same as adults – just smaller.the same as adults – just smaller.

Humans give live birth.Humans give live birth.

Skeletal SystemSkeletal SystemCrayfishCrayfish

A crayfish is a crustacean with a A crayfish is a crustacean with a hard exoskeleton and many hard exoskeleton and many specialized appendages.specialized appendages.

8 legs for walking(the front two pairs taste food)

6 antennae for smelling

Two large claws for defense

Many different mouthparts for handling food

Small feathers on the tail segments for swimming

ExoskeletonExoskeleton

All of their appendages are formed of All of their appendages are formed of chitinchitin – the exoskeleton. – the exoskeleton.

Crayfish cannot grow larger than their Crayfish cannot grow larger than their skeleton and must skeleton and must moultmoult it regularly. it regularly.

The crayfish is soft and weak for a The crayfish is soft and weak for a short period while the new skeleton short period while the new skeleton grows.grows.

MoultingMoulting

In HumansIn Humans

The skeleton is The skeleton is withinwithin the body. the body.

The body tissues are able to grow The body tissues are able to grow around the skeleton.around the skeleton.

Thankfully, you never have to take Thankfully, you never have to take your bones out and replace them.your bones out and replace them.