Post on 23-Feb-2016
description
BIVALVES AND GASTROPODSMae Gallego 9A
Kingdom: Animalia G. Phyla: Molusca
i.)Sub-phyla: Gastropods/Bivalves
GASTROPODA
From ancient Greek Prefix γαστήρ gastr- stomach Sufix πούς pod- foot 325,000 species currently existing
-only 85 thousand have accepted names
GASTROPOD CHARACTERISTICS
Have shell Univalves Torted body Anus and head are together Well defined head 2-4 sensory tentacles with eyes Moves gliding along a surface Leaves mucus or slime produced
by glands on the foot. Invertabrate
BIVALVIA Name describes the shape of the shell. Also known as:
Pelecypoda (axe foot) Acephala (no head) Lamellibranchia (plate-like gill elements)
aprox. 9,200 species
CHARACTERISTICS Shell (2 asymmetrically rounded
halves) Made of calcium carbonate
Hinge (flexible ligament that joins the valves)
Most live in water No defined head Breathe-only one/two pairs of gills Have no brain Can live in water with a pH greater
than 5 Mostly sedentary
GASTROPOD FOSSIL RECORD Most are fossils of the shell
Few slug fossils Earliests-exclusively marine (end of
Cambrian)
BIVALVE FOSSIL RECORD 1st from the Cambrian
period 510 million years ago
Most abundant during the Devonian period 400 million years ago
During Paleozoic period- near shore enviroments.
GASTROPOD LIFE CICLE
BIVALVE LIFE CYCLE
DIGESTIVE SYSTEM Gastropods:
Mostly hervibores or scavangers Use radula to eat
tongue-like structure-rows of rasping teeth. Adapts to the food it eats
Stomach is above foot Vivalves:
Filter feeding (gills) Scraping detritus from bottom (most primitive) Intercellular digestion
RESPIRATORY SYSTEM Lungs or gills
Depending on the habitat Respiratory protein: Hemocyanin Bivalves
Water currents enable the organism to get fresh oxygen.
CIRCULATORY SYSTEM Open circulatory system Gastropods:
2 chamber heart Auricle (recieves the haemolymph) Ventricle (pumps haemolymph into the aorta)
Haemolymph Circulatory fluid
Short aorta Divided in 2 main vessels
Bivalves: 3 chamber heart
SENSORY SYSTEM Gastropods
Olfactory Mechanorceptor Statocyst Eyes or visual organ Central nervous
system Bivalves
Poor nervous system and sensory organs
Chemosensory cells at edge of mantle
ANY QUESTIONS, COMENTS ETC?
BIBLIOGRAPHY http://www.google.es/imgres?q=snail+circulatory+system&um
=1&hl=es&biw=1360&bih=634&tbm=isch&tbnid=F36RH2-OyisixM:&imgrefurl=http://myclasses.naperville203.org/staff/NNHSBiology/KraftsonEco/Animal%2520Kingdom%2520%2520Period%25202/Mollusca.aspx&docid=WyxdXLXKu-cJXM&imgurl=http://www.biologie.uni-hamburg.de/b-online/library/onlinebio/circsys_2.gif&w=502&h=314&ei=Yh5BT6eZBcTE0QX6sJ2PDw&zoom=1&iact=hc&vpx=348&vpy=308&dur=5644&hovh=177&hovw=284&tx=60&ty=71&sig=101967442354638864406&page=1&tbnh=110&tbnw=176&start=0&ndsp=18&ved=0CF0QrQMwBw
http://en.wikipedia.org/wiki/File:CyprusPlioceneGastropod.JPG http://en.wikipedia.org/wiki/Fossil_record http://en.wikipedia.org/wiki/Gastropoda http://www.natureduca.com/zoo_inverteb_moluscos3.php http://encina.pntic.mec.es/nmeb0000/invertebrados/moluscos/
gruposmoluscos/gasteropodos.html http://www.scholarpedia.org/article/Gastropod_reproductive_be
havior http://en.wikipedia.org/wiki/Gastropoda http://www.manandmollusc.net/advanced_introduction/moll101
gastropoda.html http://micropig.tumblr.com/post/807759651/dragon-slug-how-d
o-you-exist http://www.google.es/search?q=slug&um=1&ie=UTF-8&hl=es
&tbm=isch&source=og&sa=N&tab=wi&ei=5kBBT4LwGIHChAepwZ3OBQ&biw=1360&bih=634&sei=n0FBT4mNOMaEhQfuw7XEBQ
http://www.manandmollusc.net/advanced_introduction/mollusca_101_intro.html
http://www.kgs.ku.edu/Extension/fossils/bivalve.html http://infusion.allconet.org/webquest/PhylumMollusca.html http://www.waterencyclopedia.com/Bi-Ca/Bivalves.html#b