Transcript Phylum Chordata

Biology 11
A.MacAskill
 All
cells require a constant supply of:
 Oxygen
 Nutrients
 All cells need to get rid of waste products:
 Carbon
Dioxide
 Small
simple animals can use diffusion to
exchange gases ( O2 and C02) and receive
nutrients.

Ex: Sea Anemone, Flat worms
 Diffusion
is not sufficient for larger animals.
 Larger animals require a transportation
system and special gas exchange structures.
 The
Circulatory System is a Transportation
System:
 Responsible for transporting nutrients and
oxygen to cells and removing wastes and
carbon dioxide from cells. (cellular
respiration)
Open Circulatory System:
 Hemolymph is pumped by the heart into an
open cavity called the hemocoel
 Hemolymph bathes the organs directly with
oxygen and nutrients
 Muscular movements during location can help
the hemolymph circulate


ex: Arthropods, Mollusks
 Closed
Circulation System:
 Blood is always contained in vessels of
different size and thickness.
 Blood is pumped by heart through vessels to
all parts of the body.

Ex: Annelids, Chordates
 Why
are closed circulatory systems more
efficient than open?
 Single


Loop Circulation System:
Found in organisms with gills
The heart pumps blood to the gills from there it
passes directly to the tissues before being
returned to the heart.
 Double



Loop Circulation System:
Found in organisms with lungs
Blood flow has two distinct pathways
Blood flows to the lungs or to the body from the
heart

Heart : a muscular pump to move the blood

Chambers of the Heart:
 Atrium: Top chamber which receives blood
from body
 Ventricle: Bottom chamber which sends blood
to body

Septum: A thick muscular wall which separates
heart chambers
 Arteries:
large blood vessels that carry blood
from the heart to the tissues of the body
 Capillaries:
extremely small blood vessels
that allow for nutrients and oxygen to reach
tissues and carbon dioxide and other wastes
to pass from the tissues.
 Veins:
Blood vessels that carry blood from
the tissues to the heart.
 Heart
comprised of two chambers:
 One Atrium & One Ventricle
 Single loop circulation
 Blood
collected from the body enters the
Atrium
 The heart relaxes, the blood passes through
a valve into the Ventricle
 Contraction of the ventricle forces the blood
into the capillary network of the gills.
 Blood then flows to capillary network of the
body.
 Blood returns to the atrium.
 Cycle continues!
 Heart
comprised of three chambers:
 Two Atria & One Ventricle
 Double loop circulation
 Right
Atrium receives deoxygenated blood
from the body
 Left Atrium receives oxygenated blood from
the lungs and skin
 Both atria empty into the single ventricle

What is the problem with this?
 Ventricle
contracts and pumps blood to both
the body and lungs
 The cycle continues !
 Note:
Septum extends into the ventricle
 Why would this be beneficial compared to the
Amphibian?
Heart comprised of four chambers:
 Two Atrium (Right and Left)
 Two Ventricles (Right and Left)
 Double loop circulation
 Complete Septum, no mixing of blood

 Deoxygenated
blood from the body enters
the Right Atrium
 Blood flows through a valve into the Right
Ventricle
 Deoxygenated blood flows to the lungs where
gas exchange occurs
 Oxygenated blood from the lungs enters the
Left Atrium
 Blood flows through a valve into the Left
Ventricle
 Oxygenated blood flows to the body where
gas exchange occurs
 Ectotherms
are cold blooded ; not capable of
maintaining a constant body temperature
 Endotherms are warm blooded; capable of
maintaining a constant body temperature
 What are some advantages/disadvantages of
being an endotherm?
Advantage: Can be active and survive at low
external temperatures
 Disadvantage: Require high amounts of energy
(we must always eat food)

Plant Transportation System
 Plants
also need a transportation system:
 To gain nutrients and water
 To move water from the roots to the rest of
the plant
 To move nutrients from the leaves
to the rest of the plant
 Plants
are divided into two groups:
 Non-vascular:
do not contain vascular tissue
 Vascular: contain vascular tissue
Plant Transportation Mechanism:
Xylem
Xylem
Structure:
 Long hollow tube extending from the
root
 Is Dead Tissue
Xylem
Function:
 Transportation of water from the
roots to the rest of the plant
 Walls are thick to provide structure
to the stem
Plant Transportation Mechanism:
Phloem
Phloem
Structure:
 Bidirectional flow
 Living Tissue
Phloem
Function:
 Transportation of nutrients from the
leaves to the rest of the plant
Characteristics of Non-Vascular
Plants
 Do
not have roots, stems or leaves
 Lack vascular tissue
 This
limits the size of the plant because it
cannot transport water and food very far
 Are
small in size
 Depend on water for reproduction
 Cannot
survive in dry areas
 Examples:
Mosses,
Liverworts, Hornworts
Characteristics of Vascular Plants
 Have
true roots, stems, and leaves
 Have vascular tissue (vascular bundles):


Xylem: Transports water
Phloem: Transports nutrients
 Are
capable of reproduction
on land
 Two types of flowering plants:
 Monocots
 Dicots
Monocots- Vascular Plant
 Leaf
veins are parallel and extend the length
of the leaf
 One cotyledon: first leaf to germinate
 Vascular bundles: are scattered in the stem
 Flower parts arranged in three’s
 Ex: Grass, Cattails, Lilies, and Palmtrees
Dicots- Vascular Plants
 Have
leaves with net-like veins
 Leaf veins are parallel and extend the length
of the leaf
 Vascular bundles: arranged into a cylinder
 Flower parts arranged in four’s or five’s
 Increase their diameter each year
Lab Time!
 Follow
Instructions on your lab sheet.