invert comparison part 2

invert comparison part 2 - Transcript

Circulation
 All cells in multicellular animals require
 a constant supply of oxygen & nutrients
The removal of nitrogenous wastes

Circulation
 Small, thin animals use ______________.
 Typically complex animals use one or
more hearts and either an open or closed
circulatory system.

Open Circulatory System
 Open Circulatory System:
Definition.
Examples:

Open Circulatory System
 Open Circulatory System:
Blood is only partially contained within a
system of blood vessels.
Examples: arthropods & mollusks

Closed Circulatory System
 Definition:
 Examples:

Closed Circulatory System
 Closed Circulatory System: a heart or
heart-like organ forces blood through
vessels that extend throughout the body.
Blood stays in these vessels
Materials reach body tissues by diffusing
across the walls of the vessels.
 Annelids & mollusks

Excretion
 Cellular waste products not digestive
waste.
 Cellular wastes are created when cells
break down proteins releasing ammonia.
 Ammonia is also known as nitrogenous
waste and is toxic.

Excretion
 Excretion: the elimination of metabolic
wastes such as ammonia.
 Getting rid of wastes requires water so
excretory systems maintain water balance
in the animal.
 Excess water is also eliminated by
excretory system.

Excretion
 Most animals have an excretory system
that rids the body of metabolic wastes
while controlling the amount of water lost
or in the tissues.

Excretion – Aquatic Invertebrates
 Aquatic Invertebrates: ammonia is
released by diffusion.
Flatworms have a network of flame cells to
eliminate extra water.

Excretion – Land Invertebrates
 Land Invertebrates must conserve water
while removing nitrogenous wastes.
Convert ammonia to less toxic compounds

Excretion – Land Invertebrates
 Annelids & mollusks: produce urea which
is diluted to form urine in the nephridia

Excretion – Land Invertebrates
 Insects & spiders: produce uric acid (very thick
so it conserves water) in the Malpighian
tubules and then mixed with digestive wastes
to be eliminated.

Response – nervous system
 Nervous systems gather and process
information from the environment allowing
animals to respond to their environment.

Response – nervous system
 Three trends in the evolution of
invertebrates are seen in invertebrate
species:




Response – nervous system
 Three trends in the evolution of
invertebrates are seen in invertebrate
species:
 centralization
 cephalization
 specialization

Response – nervous system
 Centralization: Flatworms and round
worms have more concentrated or
centralized nerve tissue (ganglia).

Response – nervous system
 Cephalization: mollusks & arthropods the
ganglia are organized into a brain that
controls and coordinates the nervous
system.

Response – nervous system
 Specialization: the more complex an
animal’s nervous system – the more
developed its sense organs.

Movement & Support
 Muscles typically work with a skeletal
system to support the animal and allow
movement.
What are the three types of skeletal
systems in invertebrates?

Movement & Support
 Hydrostatic Skeleton:
Examples: annelids & cnidarians
 Exoskeletons:
Arthropods & bivalves
 Endoskeletons:
Echinoderms
Preview - vertebrates

Sexual & Asexual Reproduction
 Most invertebrates reproduce sexually at
some point in their life cycle.
 Some also reproduce asexually depending
on environmental conditions.

Sexual & Asexual Reproduction
 External fertilization:
 Internal fertilization:

Sexual & Asexual Reproduction
 External fertilization: eggs are fertilized
outside the female’s body
 Internal fertilization: eggs are fertilized
inside the female’s body.