Mammals/ Mammals/ MammaliaMammalia

By Tyer Giles and Kyra Watson

Structure and Structure and CoveringCoveringMammals are Vertebrates

They also have:

Hair

Three middle ear bones

Mammary glands that function in mothers

with developing offspring

They may have sweat glands and specialized teeth

Placenta, which feeds the offspring during gestation.

A brain with a neocortex

Gas ExchangeGas Exchange Mammals exchange gas through their lungs.

Mammals hearts’ have four chambers.

Mammals are endotherms.

HeartsHeartsTemperature Temperature MaintenanceMaintenance

Fertilization and Fertilization and DevelopmentDevelopment Fertilization and development

occurs internally in mammals.

Development occurs in the

amniotic sac.

The one exception to this is

platypi who lay amniotic eggs.

SubgroupSubgroupss

Eutheria- deer, bears, mice, dolphins, elephants, monkeys,

manatees

Metatheria- opossums, shrew, wombat, bandicoots, kangaroos

Prototheria- spiny anteaters and platypus

Other Important Parts of a Mammal’s Other Important Parts of a Mammal’s Life CycleLife Cycle After several months or years mammals sex organs develop into

maturity.

Female mammals are only fertile for certain periods of time,

when they are said to be “In Heat”.

With particular mammals called marsupials after giving birth

their joeys or offspring climb into a pouch and attaches to a

teat.

-They continue to receive nutrition and develop in the

pouch.

Picture and Information SourcesPicture and Information Sources http://www.enchantedlearning.com/subjects/mammals/classification/index.shtml

http://www.ucmp.berkeley.edu/vertebrates/tetrapods/amniota.html

http://www.billcasselman.com/dictionary_of_medical_derivations/dmd_eight.htm

http://php.med.unsw.edu.au/embryology/index.php?title=2009_BGD-B_Lecture_Face_and_Ear&oldid=35150

http://blog.coturnix.org/2010/07/27/science-blogging-networks-what-why-and-how/

http://www.topnews.in/gene-variants-determine-lung-function-vulnerability-maternal-smoking-2144160

 http://www.puguhills.com/images/forests/black%20and%20rufous%20elephant%20shrew.JPG

http://www.newworldencyclopedia.org/entry/Life_cycle#Mammal_reproduction_and_early_life_cycle

Crustaceans and Crustaceans and ArachnidsArachnids

Phylum and ClassPhylum and Class

Both Arachnids and Crustaceans are a part of

the phylum arthropoda.

Arachnids class is Arachnida

Crustaceans class is Crustacea

Symmetry Symmetry Both crustaceans and arachnids are bilaterally

symmetric.

Presence or Absence of Body Presence or Absence of Body

CavityCavityArthropods do have ceolems but it is reduced.Arthropods do have ceolems but it is reduced.

Tissue LayersTissue Layers Arthropods are triploblastic meaning they have

three layers of germ tissue.

Embryonic development of Embryonic development of

ArthropodsArthropods Arthropods are protostomes, their blastophores Arthropods are protostomes, their blastophores

becomes their mouths.becomes their mouths.

Body Structure and CephalizationBody Structure and Cephalization Both Arachnids and Crustaceans have an abdomen Both Arachnids and Crustaceans have an abdomen

and a cephalothoraxes. and a cephalothoraxes.

Generally arthropods show cephalization.Generally arthropods show cephalization.

Crustaceans and Arachnids Body Crustaceans and Arachnids Body StructuresStructures

Digestive

They have a complete digestive tube;

possess a mouth and an anus.

Nervous

Anterior region of the body has a

group of ganglia forming a brain.

Group of ganglia connects to ventral

ganglial chains that have motor and

sensory nerves.

Crustaceans and Arachnids Body Crustaceans and Arachnids Body Structures (cont’d)Structures (cont’d)

Respiratory

Have an open respiratory system called a lacunar.

Hemolymph or blood is pumped by the heart and goes to

lacunas or cavities to drain tissue and irrigate blood.

Circulatory

Have hemocyanin, or respiratory pigments that carry

oxygen and other gases to circulatory fluids.

LifecycleLifecycle

Arachnids

Life cycle stages are egg, larvae,

nymph, and spider

Nymph molt several times

During mating, male spider usually

courts the female. He uses a palp

covered with sperm to fertilize the

female.

Lifecycle (cont’d)Lifecycle (cont’d)Crustacean

Life cycle stages are egg, pre-larve, pre-zoea,

and larval stages such as nauplius when one eye

has formed, zoea when thoracic appendages are

used for swimming and post-larva when abdominal

appendages are used for propulsion.

ExamplesExamples

ArachnidsBlack widow spider, tarantula

CrustaceansPill bugs, shrimp

Sources for Information and PicturesSources for Information and Pictures http://www.biology-questions-and-answers.com/phylum-

arthropoda.html http://arthropods.nhm.org/arthropods.html http://www2.volstate.edu/msd/BIO/1020/lab4Arthropoda.htm http://www.bio.brandeis.edu/fieldbio/arachnids_cohen_weiner/

Intro.html  http://healthyhomegardening.com/images/heidbenati/tatu2.jpg http://islandwood.org/kids/stream_health/key/BAABBA.html http://www.freeinfosociety.com/media/images/3952.jpg