biod cephalopods

8/2/2019 biod cephalopods

1/38

SBB3023 - Biodiversity AndEvolution Of Protista AndAnimalia

NAME MATRIC NO

NABILAH BINTI KOMARUDDIN D20101037466

NUR SYAFIQAH BINTI ABD KADIR D20101037567

NAZRATUL ILYANA BINTI MOHAMAD D20101037470

YANTIE BINTI MAKLIN D20101037471

RIDWAN BIN SHAMSUDIN D20101037472

MARIAMAH BINTI ARON D20101037477


2/38


3/38


4/38


5/38


6/38

1.Most advance, intelligent invertebrates (squid,

nautilus, octopus, cuttlefish)

2. Included squid,octopus,nautilses and cuttlefish

3. have well developed senses and large brain (larger

than those of gastropods)

4.All marine

5.All predators (giant squid is the largest invertebrate)


7/38

6. They can also change texture and body shape

7. Cephalopods have advanced vision, can detect gravity

with statocysts, and have a variety of chemical sense organs

8. cephalopods lack a cornea, and have an everted retina

9.Most cephalopods possess chromatophores that is, coloured

pigment

10.cephalopods have an ink sac, which can be used to expel a

cloud of dark ink to confuse predators

11. closed circulatory system.3 heart


8/38

12.Nautiluses are the only extant cephalopods with

an external shell

13.Shell variable

Nautilusmulti-chambered gas-filled shell

Cuttlefish -cuttleboneinternal shell

Squidinternal shell (pen)

Octopusno shell

14.Reproduction -Dioecious, internal fertilization,

eggs fertilized by males then leave oviduct of

female and land on sea floor


9/38

Shell


10/38

The earliest shells werestraight cones.

Others had curved orcoiled shell such asammonoids andnautiloids.

The early nautiloid and

ammonoid shell areheavy cause buoyancy bya series of gas chambers.(eg: Nautilus)

This enable the animal toswim while carrying itsshell.


11/38


12/38

The shell ofNautilusis coiledbut quite differ from

gastropod. Transverse septa divide the

shell into internal chambers.

The living animal inhibits only

the last chamber. As it grows, it moves forward,

secreting behind it newseptum.

The chambers are connectedby a cord of living tissue calledsiphuncle.


13/38


14/38

Cuttlefish have asmall, coiled or

curved shell, but itis entirely enclosedby the mantle.

Squids have no

shell. But leavingonly a thin, flexiblestrip called a pen,which the mantle

enclosed.Octopus have no

shell.

Cuttlefish

squids

Octopus


15/38

Body andMantle


16/38

NAUTILUS the head with its tentacles can be extruded

from the opening of the body compartment ofthe shell.

Its 60-90 or more tentacles have no suckersbut adhere to prey by secretions.

The tentacles search for, sense and grasp food.

The head is the funnel.The shell shelters the mantle, mantle cavity

and visceral mass.


17/38

Other than Nautiloids

Have only one pair of gills.

Octopuses have 8 arms with suckers.

Squids and cuttlefishes have 10 arms (8 out of10 with suckers and the other 2 is retractile

tentacles.)

Thick mantle allowing water to be taken into

the mantle cavity


18/38

Cephalopods

They have a closed circulatory system with anetwork of vessels.

Blood flows through the gills via capillaries.

Branchial (gill) hearts, or accessory heartsincrease the blood pressure in the gills whichpermits more rapid gas exchanges.

Have well-developed nervous systems-mostcomplex brain among invertebrates.

Nautilus has simple eyes but others haveelaborate eyes with cornea, lens, chambers and aretina.


19/38


20/38

COLOUR CHANGES

Cephalopods has special numerous pigment-

filled bags called chromatophores in the skin.

Chromatophores are found in the skin, and

expand and contract to reveal or conceal small

dots of color.

Color changes in cephalopods is controlled by

the nervous system and hormones.


21/38

The color changes are used for camouflage orto startle and warn potential predators in theirundersea realm.

Cephalopods are believed has lack colorvision, it is proven in the experiments.

The photoreceptor of cephalopods arerhabdomere cells. Hence, their ability to see

color depends on the number of pigmentspresent.


22/38

The fluid is released through the

anus to form a smokescreen to

confuse an enemy.

Most cephalopods have

an ink sac that empties

into the rectum.

The sac contains an ink

gland that secretes a

dark fluid containing thepigment melanin.


23/38

Locomotion


24/38

Swim

by force expelling water from mantle cavitythrough ventral funnel.

Funnel is mobile ( to control direction,

forced expulsion of water determinedspeed)


25/38

Squid and cuttlefish

In Squid (Loligo) and cuttlefish ( Sepia )

Streamlined (for speed)

Lateral fins acts as stabilizer, rapid swimming


26/38

NautilusIn Nautilus - Gasfilled chambers keep shell

upright

Move slower compared to squid


27/38

OctopusHas globular body, no fins

Swim backward by spurting water from theirfunnel

Aid to crawling over rocksSuction disc at arm- to anchor

Some deep water octopus- have fins,arm webbedlike umbrella, swim in medusae-like

Large octopus- have flatten body and swim byundulation


28/38


29/38

Reproductionof

Class Cephalopoda


30/38

Sexes are separate

Internal fertilization

involves elaborate color changes

cuttlefish


31/38

OctopusMales changes in skin pigmentation and

patterning

Attract towards females and against rival

males

undergo copulation process


32/38

Copulation process

Adult males produces aspecial arm or modifiedarm called ahectocotylus

Then transfers a sperm

packet to the female'spallial cavity

plucks aspermatophores fromhis own mantle cavityand inserts it into themantle cavity of femalenear the oviductopening

Arrow 1 :The spermatophore

groove of the inserted

hectocotylus.

Arrow 2 :

An oviducal gland


33/38

The female lays a number of

eggs

Some octopuse tends their eggs - guard their eggs

They clean them, provide them with fresh water anddefend them against enemies

The female octopus does not eat as long a she guardsthe eggs. Often she dies after her offspring's hatching,

because she is too weak to defend herself against herenemies


34/38

1 2

34

56

P


35/38

Phylogeny and

Adaptivediversification

Ph l


36/38

Phylogeny


37/38

Adaptivediversification Cephalopoda have a greatlyexpanded visceral mass.

In cephalopoda the mantle cavitywas extended ventrally.

Evolution of chambered shell in

cephalopodo was are very importantcontribution to their freedom from thesubstrate and their ability to swim.

Elaboration of their respiratory,circulatory, and nervous system is

correlated with their predatory andswimming habits.

Diversity is related to theiradaptation to different habitat, feedingmethods and mode of life.


38/38

END

biod cephalopods

Documents

Transcript of biod cephalopods