S B B 3023 -Bi o d i v e r s i t y An d E v o l u t i o n Of Pr o t i s t a An d A n i ma l i aNAME MATRIC NONABILAH BINTI KOMARUDDIN D20101037466NUR SYAFIQAH BINTI ABD KADIR D20101037567NAZRATUL ILYANA BINTI MOHAMAD D20101037470YANTIE BINTI MAKLIN D20101037471RIDWAN BIN SHAMSUDIN D20101037472MARIAMAH BINTI ARON D20101037477
1.Most advance, intelligent invertebrates (squid,nautilus, octopus, cuttlefish)2. Included squid,octopus,nautilses and cuttlefish3. have well developed senses and large brain (largerthan those of gastropods)4.All marine5.All predators (giant squid is the largest invertebrate)
6. They can also change texture and body shape7. Cephalopods have advanced vision, can detect gravitywith statocysts, and have a variety of chemical sense organs8. cephalopods lack a cornea, and have an everted retina9.Most cephalopods possess chromatophores that is, colouredpigment10.cephalopods have an ink sac, which can be used to expel acloud of dark ink to confuse predators11. closed circulatory system.3 heart
12.Nautiluses are the only extant cephalopods withan external shell13.Shell variable – Nautilus –multi-chambered gas-filled shell Cuttlefish -cuttlebone –internal shell Squid –internal shell (pen) Octopus –no shell14.Reproduction -Dioecious, internal fertilization,eggs fertilized by males then leave oviduct offemale and land on sea floor
• The earliest shells were straight cones.• Others had curved or coiled shell such as ammonoids and nautiloids.• The early nautiloid and ammonoid shell are heavy cause buoyancy by a series of gas chambers. (eg: Nautilus)• This enable the animal to swim while carrying its shell.
• The shell of Nautilus is coiled but 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 new septum.• The chambers are connected by a cord of living tissue called siphuncle.
Cuttlefish have a small, coiled or curved shell, but it is entirely enclosed by the mantle. Cuttlefish Squids have no shell. But leaving only a thin, flexible strip called a pen, which the mantle enclosed. squids Octopus have no shell. Octopus
NAUT I L US the head with its tentacles can be extruded from the opening of the body compartment of the shell.Its 60-90 or more tentacles have no suckers but 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.
Ot h e r t h a n Na u t i l o i d sHave only one pair of gills.Octopuses have 8 arms with suckers.Squids and cuttlefishes have 10 arms (8 out of 10 with suckers and the other 2 is retractile tentacles.)Thick mantle allowing water to be taken into the mantle cavity
Ce p h a l o p o d s They have a closed circulatory system with a network of vessels. Blood flows through the gills via capillaries. Branchial (gill) hearts, or accessory hearts increase the blood pressure in the gills which permits more rapid gas exchanges. Have well-developed nervous systems-most complex brain among invertebrates. Nautilus has simple eyes but others have elaborate eyes with cornea, lens, chambers and a retina.
COL OUR CHA NGE S 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.
The color changes are used for camouflage or to startle and warn potential predators in their undersea realm.Cephalopods are believed has lack color vision, it is proven in the experiments. The photoreceptor of cephalopods are rhabdomere cells. Hence, their ability to see color depends on the number of pigments present.
The sac contains an inkMost cephalopods have gland that secretes aan ink sac that empties dark fluid containing the into the rectum. pigment melanin. The fluid is released through the anus to form a “smokescreen” to confuse an enemy.
Swimby force expelling water from mantle cavitythrough ventral funnel.Funnel is mobile ( to control direction,forced expulsion of water determinedspeed)
Sq u i d a n d c u t t l e f i s hIn Squid (Loligo) and cuttlefish ( Sepia )Streamlined (for speed)Lateral fins – acts as stabilizer, rapid swimming
Na u t i l u sIn Nautilus - Gas filled chambers keep shelluprightMove slower compared to squid
Oc t o p u sHas globular body, no finsSwim backward by spurting water from their funnelAid to crawling over rocksSuction disc at arm- to anchorSome deep water octopus- have fins,arm webbed like umbrella, swim in medusae-likeLarge octopus- have flatten body and swim by undulation
Re p r o d u c t i o n o f Cl a s sCe p h a l o p o d a
Sexes are separateInternal fertilizationinvolves elaborate color changes cuttlefish
Oc t o p u sMales changes in skin pigmentation and patterningAttract towards females and against rival malesundergo copulation process
Co p u l a t i o n pproduces a c e s s Adult males r o special arm or modified arm called a hectocotylus Then transfers a sperm packet to the females pallial cavity plucks a spermatophores from his own mantle cavity Arrow 1 : and inserts it into the The spermatophore mantle cavity of female groove of the inserted hectocotylus. near the oviduct Arrow 2 : opening An oviducal gland
The female lays a number of eggs Some octopuse tends their eggs - guard their eggs They clean them, provide them with fresh water and defend them against enemies The female octopus does not eat as long a she guards the eggs. Often she dies after her offsprings hatching, because she is too weak to defend herself against her enemies
Ad a p t i v e di v e r s i f i c a t i on Cephalopoda have a greatlyexpanded visceral mass. In cephalopoda the mantle cavitywas extended ventrally. Evolution of chambered shell incephalopodo was are very importantcontribution to their freedom from thesubstrate and their ability to swim. Elaboration of their respiratory,circulatory, and nervous system iscorrelated with their predatory andswimming habits. Diversity is related to theiradaptation to different habitat, feedingmethods and mode of life.