1. The document discusses the biodiversity and evolution of protists and animals, specifically focusing on cephalopods. It describes the key characteristics of cephalopods including their shells, bodies, senses, color changing abilities, and locomotion. 2. The reproduction processes of cephalopods are explained, involving internal fertilization and elaborate mating behaviors and color changes in some species. 3. Adaptive diversification of cephalopods is discussed, with the evolution of traits like chambered shells, advanced organ systems, and habitat/feeding adaptations leading to their diversity of forms.

1. 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 a
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

6. 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. 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. 12.Nautiluses are the only extant cephalopods with
an external shell
13.Shell variable –
Nautilus –multi-chambered gas-filled shell
Cuttlefish -cuttlebone –internal shell
Squid –internal shell (pen)
Octopus –no shell
14.Reproduction -Dioecious, internal fertilization,
eggs fertilized by males then leave oviduct of
female and land on sea floor

9. Sh e l l

10. • 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.

12. • 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.

14.  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

15. Bo d y
a n d
Ma n t l e

16. 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.

17. Ot h e r t h a n
Na u t i l o i d s
Have 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

18. 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.

20. 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.

21.  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.

22. The sac contains an ink
Most cephalopods have gland that secretes a
an 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.

23. L o c o mo
t i o n

24. Swim
by force expelling water from mantle cavity
through ventral funnel.
Funnel is mobile ( to control direction,
forced expulsion of water determined
speed)

25. Sq u i d a n d
c u t t l e f i s
h
In Squid (Loligo) and cuttlefish ( Sepia )
Streamlined (for speed)
Lateral fins – acts as stabilizer, rapid swimming

26. Na u t i l u s
In Nautilus - Gas filled chambers keep shell
upright
Move slower compared to squid

27. Oc t o p u s
Has globular body, no fins
Swim backward by spurting water from their
funnel
Aid to crawling over rocks
Suction disc at arm- to anchor
Some deep water octopus- have fins,arm webbed
like umbrella, swim in medusae-like
Large octopus- have flatten body and swim by
undulation

29. Re p r o d u c
t i o n
o f
Cl a s s
Ce p h a l o p
o d a

30. Sexes are separate
Internal fertilization
involves elaborate color changes
cuttlefish

31. Oc t o p u s
Males changes in skin pigmentation and
patterning
Attract towards females and against rival
males
undergo copulation process

32. 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 female's
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

33.  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 offspring's hatching,
because she is too weak to defend herself against her
enemies

34. 1 2
3 4
5
6

35. y a n d
Ad a p t i v e
d i v e r s i f
i c a t i o n

36. Ph y l o g e
n y

37. Ad a p t i v e
di v e r s i f
i c a t i on
 Cephalopoda have a greatly
expanded visceral mass.
 In cephalopoda the mantle cavity
was extended ventrally.
 Evolution of chambered shell in
cephalopodo was are very important
contribution to their freedom from the
substrate and their ability to swim.
 Elaboration of their respiratory,
circulatory, and nervous system is
correlated with their predatory and
swimming habits.
 Diversity is related to their
adaptation to different habitat, feeding
methods and mode of life.

38. END