Bio: Circulatory Systems and Immunology Flashcards
Plant circulation
Translocation
What is the primary organ of transport in the plant?
Stem
Vascular bundles
Run up and down the stem
Fibrovascular bundle
Center of the stem contains xylem, phloem, cambium
Xylem
thick walled, hollow cells INSIDE vascular bundle.
Carry water and minerals up the plant and their thick walls give the plant its rigid support.
outer layer of xylem is alive. called sapwood.
Two types of xylem cells
Vessel cells and tracheids
Transpiration pull
Rise of water in xylem
As water evaporates from the leaves of plants, a vacuum is made that pulls water up the stem
Capillary action
Rise of water in xylem
Any liquid in a thin tube will rise due to the surface tension of the liquid and interactions between the liquid and the tube
Root pressure
Rise of water in xylem
Water entering the root hairs exerts a pressure that pushes water up the stem.
Phloem
Thin walled cells on the outside of the vascular bundle.
Transport nutrients down the stem.
Phloem cells are living
Types of phloem cells
Sieve tube cells and companion cells,
Cambium
Two layers thick. Actively dividing. undifferentiated cells that give rise to xylem and phloem.
(In between x and p cells)
Cells near phloem differentiate into phloem. x into x.
Layers in plant stem. out to in
Epidermis (outerbark) > Cortex > Phloem > Cambium > Xylem > Pith (tissue involved in storage of nutrients and plant support)
Root
Root functions to ABSORB materials via root hairs and to ANCHOR the plant.
Root hairs
specialized cells of root epidermis with thin walled projections.
increase SA for absorption of water and minerals from the soil.
Has layers just like the stem.
Circulation in invertebrates (4)
Protozoans. Cnidarians. Arthropods. Annelids.
Protozoan circulation
Invertebrate.
Movement of gas and nutrients is accomplished by simple diffusion within the cell
Cnidarian circulation
Invertebrate.
Hydra and other cnidarians have body walls TWO CELLS THICK.
all cells are in direct contact with either the internal or external environments, so there is no need for specialized circulatory system.
Arthropod circulation
Invertebrate.
OPEN CIRCULATORY SYSTEM. in which blood (interstitial fluid) is in direct contact with body tissues.
Blood is circulated primarily by body movements.
Blood flows through a dorsal vessel into sinuses (where exchange occurs)
Annelid circulation
Invertebrate.
Earthworm. CLOSED CIRCULATORY SYSTEM.
Deliver materials to cells that aren’t close to external environment. Blood is confined to vessels and moves toward head in the dorsal vessel, which functions as the main heart by contractions.
5 pairs of vessels called aortic loops connect the dorsal vessel to the ventral vessel and function as additional pumps.
No RBC. Hemoglobin like pigment dissolved in aqueous solution.
Functions of blood
Transports nutrients and O2 to tissues and removes wastes and CO2 from tissues.
Platelet function
injury repair
Leukocytes
Main component of immune system.
Erythrocytes
Erythrocytes transport O2 via circ system.
Hemoglobin molecules in erythrocytes BIND to O2.
Hemoglobin also binds to CO2 when O2 dissociates
Bicarbonate buffering system
CO2 gas in the body, including the blood, is to provide an important reactant for the bicarbonate buffering system.
CO2 combines with H2) to make H2CO3 (carbonic acid) which dissociates into bicarbonate (HCO3- weakbase) and H+ (acidic H)
Simple shifts in chemical eq of system via respiration in lungs or cells can accommodate pH imbalances in body.
Blood is a vip buffer as it is a carrier for thecrucial gases and ions used in the system.
Amino acids and Simple sugars are absorbed into the bloodstream at the..
Intestinal capillaries
Where do metabolic waste products diffuse into?
Metabolic waste products diffuse into capillaries from surrounding ells. These wastes are delivered to appropriate excretory organs.
Human cardiovascular system
composed of a muscular four chambered heart, a network of blood vessels, and the blood.
