Transcript Unit VI Anatomy and Physiology of Plants and Animals

Unit VI
Anatomy and Physiology of
Plants and Animals
Learning Goal 1
Identify the major classification
schemes of kingdoms Plantae and
Animalia
Kingdom Plantae
• Plant Adaptations to
Life on Land
• Cuticle
Waxy outer covering that
helped plants prevent
water loss.
Stomata
Tiny pores through the
cuticle that allow
exchange of gases and
release of water.
• Lignin
A tough polymer that
strengthens the walls of
plant cells and allows
plants to stay erect on
land.
• Vascular Tissue
Cells arranged in lignified
tube-like structures that
branch throughout the
plant body. Vascular
tissue in plants helps
distribute water and
nutrients.
• Root and Shoot
Systems
To grow on land
plants developed
roots to anchor them
in soil and absorb
water and nutrients.
Shoot systems have
stems and leaves for
absorbing sunlight
and gas exchange.
Nonvascular Plants
• Bryophites
Consist of liverworts,
hornworts, and mosses.
Do not have true roots, stems,
and leaves.
Must live in moist
environments due to lack of
such tissues.
Male and female
gametophytes produce
gametes in structures called
antheridia(male) and
archegonia (female). Sperm is
motile and must swim to the
egg for fertilization. A spore
producing sporophyte
develops.
Seedless Vascular Plants
• Phylum Lycophyta
Consist of about
1,000 species of
plants known as club
mosses.
Have simple leaves,
true roots, and live in
wet, shady
environments.
• Phylum Pterophyta
13,000 species of
ferns, whisk ferns,
and horsetails.
More complex leaves
and stems.
Small gametophyte
generation with the
sporophyte being
dominant. Spores
produced in sori on
the underside of
leaves.
Vascular Plants that Produce
Seeds
• Gymnosperms
Consists of cycads, ginkgoes,
gnetophytes, and conifers.
Term gymnosperm means
naked seed.
In conifers (the most numerous
group) seeds develop in cones
once pollination occurs.
Most conifers are evergreens,
keeping leaves year-round and
thrive in cool arid
environments.
Angiosperms: Flowering Plants
• Most successful group of
plants.
• Made up of two major groups,
monocots and eudicots.
• Monocots have a single
cotelydon or seed-leaf in their
seeds. Include grasses,
palms, lilies, and orchids.
• Eudicots (dicots) have two
cotyledons and include shrubs,
trees, most non-woody or
herbaceous plants and cacti.
• Seeds form within female
portion of flowers
surrounded by a fruit.
• Fruits give protection to
the seed as well as
provide a way for
dispersal.
• Flowering plants and their
pollinators have
coevolved to the benefit
of both.
Kingdom Animalia
Characteristics
Common to Animals
Multicellular
Eukaryotic
No cell walls
Heterotrophic
Generally motile
Animal Innovations
• Tissues and Tissue Layers
As embryos of most animals
develop they form cell layers.
The inner layer called the
endoderm becomes the lining
of the gut and other organs,
The outer ectoderm forms the
external covering and nervous
system.
Between is the mesoderm
which becomes the muscles
and other structures between
the gut and the external
covering.
• Radial or Bilateral Symmetry
Animals that exhibit radial
symmetry have body parts
arranged around a central axis.
This includes two phyla,
Cnidaria ( hydras, jellyfishes,
and sea anemones) and
Ctenophora (comb jellies)
All other animal phyla have
bilateral symmetry in which a
cut along the midline from
head to tail would divide them
into mirror images.
• Body Cavities
Acoelomate – animals without
a body cavity. Have a
continuous mass of tissue
between the gut and the body
wall. Includes phylum
Platyhelmenthes (flatworms).
Pseudocoelomate- animals
with a fluid or organ filled
space between the gut and the
body wall. Includes phyla
Nemotoda (round worms) and
Rotifera.
Coelomates – animals with a
true coelom, a fluid-filled body
cavity lined by a peritoneum.
•
•
Developmental Patterns
Protostomes
Includes most invertebrate phyla.
As the zygote (fertilized egg) divides
by mitosis it exhibits a pattern of spiral
cleavage.
Cleavage is determinate, meaning that
each cell’s development is determined
as the cell is produced. In other words
it won’t develop on its own.
Deuterstomes
Includes some invertebrates and all
vertebrate phyla.
Embryos exhibit radial cleavage.
Early cells of the embryo have
indeterminate cleavage where an
isolated cell can develop into a
functional embryo
Animal Classification
•
Parazoa
Includes only one group, the
sponges.
Phylum Porifera
Lack true tissues with simple body
plans.
Filters food particles from
surrounding water in a central
chamber.
Most are hermaphroditic with
individuals producing both sperm
and eggs.
Zygotes develop into flagellated
larvae that attach to substrates
becoming sessile adults.
Eumetazoans
•
Cnidarians
8900 species, nearly all of which
live in the sea.
Exhibit radial symmetry with a
body plan organized around a
saclike gastrovascular cavity.
The mouth is ringed with tentacles
for food gathering.
May exhibit a polyp or a medusa
body structure or alternate
between both.
Major groups include the hydrozoa
(hydra), Scyphozoa (jelly fishes),
Cubozoa (box jelly fish), and
Anthozoa (corals and sea
anemones).
All have nematocysts which are
encapulated coiled threads
containing toxins that can paralyze
small prey.
• Ctenophores (comb
jellies)
Exhibit radial
symmetry.
Lack nematocysts.
Usually transparent
and sometimes
luminescent.
Live primarily in
coastal regions.
Lophotrochozoan Protostomes
• Lophophorates
Consist of 3 phyla,
Ectoprocta, Brachipoda,
and Phoronida.
All possess a lophophore,
a circular or U-shaped
fold with one or two rows
of hollow, ciliated
tentacles surrounding the
mouth.
• Phylum
Platyhelminthes
(flatworms)
13,000 species live in
aquatic or moist terrestrial
environments.
They are acoelomate with
no respiratory or
circulatory system.
Includes turbellarians,
trematodes (flukes),
monogenoids, and
cestodes (tape worms)
• Phylum Rotifera
Microscopic, freshwater
organisms.
Well-developed digestive,
reproductive, excretory,
and nervous systems.
They are
pseudocoelomates.
Have a wheel-like corona
lined with cilia to help
them move and eat.
• Phylum Nemertea
Also known as ribbon
worms.
Mostly marine species
from 1cm to 30 meters in
length.
Have complete digestive
and circulatory systems,
with a mucous covered
proboscis to catch prey.
• Phylum Mollusca
Contain a visceral mass
enclosed in a shell with a
muscular head-foot for
locomotion.
Have a true coelom.
Mostly marine, but some
freshwater,and terrestrial.
Contain the groups
polyplacophora (chitons),
gastropods (snails and slugs),
bivalves ( clams, mussels),
and cephalopods
(octopuses, squids, and
nautiluses)
• Phylum Annelida
Habitats are marine,
freshwater, and terrestrial.
Highly segmented body
divided into repeating units.
Digestive and circulatory
systems run the length of the
body.
Contain groups, polychaeta
(bristle worms), oligochaeta
(earthworms), and hirudinea
(leeches)
Ecdysozoan Protostomes
• General Characteristics:
• All contain an external covering that they shed
periodically.
• It helps protect them from environmental conditions.
• Phylum Nematoda
(roundworms)
80,000 described species, but
estimated that more than half a
million exist.
Many are microscopic, but can
be a meter or more long.
Have ecological, agricultural,
and medical significance.
Major decomposers, can be
parasitic on crop plants and
people.
• Phylum Arthropoda
Have segmented bodies
with as rigid exoskeleton.
Body segments consist of
the head, thorax, and
abdomen.
Consist of subphyla
chelicerata (spiders,
ticks, mites, and
scorpions), crustacea
(shrimp, lobster, crab),
myriapoda (centipedes,
and millipedes), and
hexapoda (insects)
Invertebrate Deuterstomes
• Phylum Echinodermata
6600 species of sea
stars, sea urchins and
others.
Have a well-developed
coelom.
Exhibit radial symmetry
as adults, with no head or
central brain.
Phylum Chordata
• Have a notochord, a flexible rod consisting
of fluid-filled cells surrounded by tough
connective tissue.
• Have a segmental body wall and tail
muscles.
• Contain a dorsal hollow nerve chord with a
brain-like structure at the anterior end.
• Have a perforated pharynx at some stage
of development.
Invertebrate Chordates
• Subphylum Urochordata
(tunacates or sea squirts)
Water pulled in through an
incurrent siphon with a mucous
net to trap particulate food.
• Subphylum
Cephalochordata (lancelets)
Have sense organs on
tentacles that grow from an
oral hood.
Occupy shallow marine
habitats.
Vertebrate Chordates
• Agnathans (Jawless Fishes)
Phyla Myxinoidea (hagfishes)
and Peteroyzontoidea
(lampreys).
Lack jaws, and have skeletons
conposed of cartilage.
Hagfishes are scavengers in
marine environments and most
lampreys are parasites as
adults.
Jawed Fishes
Chondrichthyes
Skates, rays, and
sharks
Have cartilagenous
skeletons
Use electroreceptors
to detect weak
electric currents
produced by other
animals.
Bony Fishes
• Fishes with bony
endoskeletons.
Have a gas-filled swim bladder
to increase buoyancy.
• Actinopterygii
Most primative are sturgeons
and paddlefishes
Teleosts are the most diverse
and successful group of bony
fishes.
• Sarcopterygii (lobe-finned
and lungfish)
Amphibians
• Carnivorous as adults, but
aquatic larvae may be
herbivores.
• Have thin, scaleless skin that
must remain moist to help with
gas exchange.
• Many have life cycles that
consist of both larval and adult
stages.
• Three major groups:
Anura (frogs and toads)
Urodela (salamanders)
Gymnophiona (caecelian)
Amniotes
• Characteristics
Tough dry skin filled with
keratin and lipids.
Reptiles and birds produce an
amniotic egg able to survive on
dry land. Consists of a shell,
four membranes for gas
exchange, a yolk and albumin
for nutrients and water.
Mammal embryos have the
same four membranes, but no
shell and implant in the wall of
the female’s uterus to obtain
nutrients and oxygen.
Testudines: Turtles
• Have the characteristic
bony shell consisting or a
dorsal carapace and a
ventral plastron.
• Ribs are fused to the
inside of the carapace
• Live in terrestrial,
freshwater, and marine
habitats.
• No teeth, but have a
keratinized beak.
• Sphenodontids (tuatara)
Only two surviving
species that live on
islands off New Zealand’s
coast.
• Squamata (lizards and
snakes)
Skin of keratinized scales
that sheds as animal
grows.
Regulate body
temperature behaviorally.
• Crocodilians
Aquatic predators on
other vertebrates.
Have a fourchambered heart and
care for their young
more like birds than
other reptiles.
Aves: Birds
• Have light weight, strong
skeletons with hollow limb
bones.
• Possess a keeled
sternum (breastbone) to
which flight muscles
attach.
• Have feathers which
provide aide in flight and
form an insulating cover.
• Have a high rate of
metabolism and maintain
a high constant body
temperature.
Mammals
• Four Key Adaptations
High metabolic rate and body
temperature.
Specialized teeth and jaws.
High degree of parental care.
Larger more complex brains.
• Mammal Groups:
Monotremes (egg layers)
Marsupials (pouched
mammals)
Placentals (young develop in
a placenta)