Transport

• The Hemolymph (circulating fluid) in invertebrates does not pass through enclosed tubes
• Instead, it is pumped by the heart to a network of channels and cavities (hemocoels) through the body
• Insects and arthropods are animals with open circulatory system The heart pumps blood into small cavities called hemocoels, where gas exchange between tissues and the hemolymph takes place
• CLOSED CIRCULATION

  The blood or the circulating fluid passes within blood vessels, that transported blood away from and back to the heart
• An earth worm is an invertebrate with closed circulatory system
• The human heart is a muscular organ

  that pumps blood to all parts of the

  body
• A typical adult heart beats approximately 72 times every minute and pumps about 5.5 liters of blood.
• The heart is composed of cardiac muscle, an involuntary, striated muscle, with associated nervous and connective tissues.
• The right side receives deoxygenated blood

  collected from the different parts of the body
• While the left side receives oxygenated blood from the lungs.
• The upper chambers are called atria (singular, atrium)
• While the lower chambers are called ventricles
• One-way valves called atrioventricular valves are located between the upper and the lower chambers
• Systemic circulation begins when oxygenated blood is

  delivered from the aorta to the different parts of the body.
• The "lub" sound is caused by the closing of the atrioventricular (AV) valves during ventricular contraction.
• The "dub" sound is caused by the closing of the valves that lead out of the heart
• BLOOD

  consists of 55% plasma, the liquid part, and 45% blood cells or formed elements
• Blood

  -composed of water, proteins, electrolytes, and other substances

  • hormones, fibrinogen, globulins, and albumin are found in blood plasma along with nutrients, waste

  products, and some dissolved gases
• Leukocytes help in the body's defense against infection and immunity
• thrombocytes are essential in blood clotting
• Erythrocytes transport oxygen and carbon dioxide.
• BLOOD VESSELS

  -serve as "highways" through which blood is

  circulated in the body.
• Arteries

  ➢ are thick-walled vessels that carry oxygenated blood from the heart to different body organs and tissues.
• The largest artery in the body is the aorta, the only artery that leads out of the left ventricle.
• Veins

  ➢ are thin-walled vessels compared to arteries, carry deoxygenated blood toward the heart
• Capillaries

  ➢ are the thinnest blood vessels made of only one layer of cells
• Capillaries

  sites through which materials

  between the blood and cells are

  exchanged
• Valves

  -are flaps of tissues that prevent the backward flow or regurgitation of blood
• William Harvey was the first to show that the heart and

  blood vessels form a continuous, closed circulatory system
• Pulmonary circulation

  -is the movement of blood from the heart to the lungs, and back to the heart.
• Systemic circulation

  • follows pulmonary circulation

  -Once blood is in the aorta of the heart, it moves out of the heart to be circulated to all parts of the body and other subsystems.
• Coronary circulation is a subsystem that supplies blood to the heart itself.
• Renal circulation is another subsystem that moves blood through the kidneys and back to the heart
• VASCULAR PLANTS

  -with xylem and phloem
• NON-VASCULAR PLANTS

  -without xylem and phloem
• NON-VASCULAR PLANTS

  -cannot grow high above the ground

  since they don’t have xylem and

  phloem tissues that can help

  transport substances
• XYLEM- vascular tissues that help in transport of water and minerals to all parts of the body
• PHLOEM- are tissues that help transport the products of

  photosynthesis to all parts of the plants
• Apoplast Pathway

  includes movement through the cell walls and the spaces between cells.
• Symplast Pathway,

  -water and minerals pass through a continuum of cytoplasm between cells, which is called plasmodesma

  (plural, plasmodesmata)