Transcript Slide 1 - Images

Diversity of Kingdoms
Unicelluar Protists, Annelid Worms,
Insects, Amphibians, Mammals,
Nonvascular Plants, Vascular Plants,
Gymnosperms, and Angiosperms
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Protists
• Protists, or unicellular
organisms, do not have a
circulatory system because
they are in direct contact
with their environment.
• They just carry out diffusion
to get nutrients into the cell
and waste out of the cell.
Once inside the cell,
nutrients are moved about
by the movement of
cytoplasm, called cyclosis.
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Annelid Worms
• Leeches, bristleworms, earthworms
• Possess a simple nervous system in which
organs in anterior segments have become
modified for sensing the environment.
• Annelids have a closed circulatory system.
– Blood carrying O2 & CO2 from body cells
flows through vessels to reach all parts
of the body.
• Segmented worms have a complete internal
digestive tract that runs the length of the
body.
– Food & soil is taken in by the mouth
eventually pass to the gizzard which is a
muscular sac that helps grind soil & food
before they pass into the intestine.
• Earth worms & leeches are hermaphrodites,
producing both eggs & sperm.
• Bristleworms have separate sexes &
reproduce sexually.
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Insects/Arthropods
• Arthropods possess an exoskeleton which protects & supports internal
tissues & provides places for attachment of muscles.
• These exoskeletons cannot grow, so they must be shed periodically.
– Shedding of the old exoskeleton is called molting.
• They have efficient respiratory structures that ensure rapid oxygen delivery
to cells.
– Terrestrial arthropods breathe through tracheal tubes.
– Others, such as spiders, use book lungs.
– Most aquatic arthropods, such as lobsters and crabs, respire though organs
called book gills.
• They have an open circulatory system.
• All arthropods have a brain; while most have sophisticated sense organs,
such as eyes and taste receptors.
• Terrestrial arthropods have internal fertilization.
• Aquatic arthropods may have internal or external fertilization.
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Amphibians
• An amphibian is a vertebrate that, with some
exceptions, lives in water as a larva and on
land as an adult, breathes with lungs as an
adult, has moist skin that contains mucus
glands, and lacks scales and claws.
• Their digestive system is very much like that
of a human.
• In the larval amphibian, gas exchange occurs
through the skin as well as the gills.
– Lungs typically replace gills when an
amphibian becomes an adult.
• The amphibian heart has three separate
chambers.
– There is some mixing of oxygen-rich and
oxygen-poor blood.
• They have kidneys that filter wastes from the
blood.
• They have external fertilization.
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Mammals
• Mammals are endotherms; their
bodies can generate heat internally.
• All mammals use lungs to breathe.
• The mammalian circulatory system
is divided into two separate loops
with a four-chambered heart.
– Oxygenated blood never mixes with
deoxygenated blood and this makes
this system very efficient.
• Mammals have highly developed
kidneys that control the composition
of body fluids.
– They filter urea from the blood.
– They retain salts, sugars, and other
compounds that the body cannot
afford to lose.
• Mammals reproduce by internal
fertilization.
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Nonvascular Plants
• These types of plants depend on water
for reproduction since they lack
vascular tissues.
• Since they lack vascular tissues, they
draw up water by osmosis only a few
centimeters above the ground.
• During at least one stage of their life
cycle, nonvascular plants produce
sperm that must swim through water to
reach the eggs of other individuals.
• There are three groups of nonvascular
plants
– Mosses
– Liverworts
– Hornworts
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Vascular Plants
• Vascular plants possess xylem and
phloem.
– Xylem: transports water
– Phloem: transports sugars
• Both forms of vascular tissue can move
fluids through the plant body, even
against the force of gravity.
• There are seedless vascular plants and
seed plants.
– Seedless: clubmosses, horsetails, and
ferns
– The seed plants are divided into two
groups.
• They have the ability to reproduce without
water by using flowers or cones, the transfer
of sperm by pollination, and the protection of
embryos in seeds.
– Gymnosperms: reproduce with seeds that
are exposed
– Angiosperms: flowering plants that contain
ovaries, which surround and protect the
embryo.
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