Exam II Study Guide Flashcards
Bryophytes
Bryophytes — “Non-Vascular Plants”
‣ No bulk flow system
• Mosses, Liverworts, Hornworts
• Bryo: Moss
• Phyte: Plant
Vascular Plants
◦ Actually have “Bulk flow” = Vascular System
- Lycophytes (Club mosses)
A. “Wolf” Plant
B. No seeds - Ferns and Horsetails
A. No Seeds for Reproduction - Gymnosperms (“Naked Seed”).
A. “Needle Like Leaves”
a. Except for the Ginkophyte
B. Have Cones instead of flowers - Angiosperms (Flowering Plants)
A. “Vessel Seed” —> Seeds are in ovary of flowers
Desiccation:
Desiccation: Desiccation refers to the state, the act, or the process of removing or extracting water content thoroughly resulting in extreme dryness.
• Roots:
• Roots: Parts of the plant that is underground
◦ Used for Structural support, gathering water and nutrients from soil
‣ Sometimes prop roots settle on the surface to give the plant additional balance.
• Shoots:
• Shoots:
◦ Stems
◦ Leaves
◦ Reproductive Organs
Leaves:
Leaves:
‣ Cuticle: Waxy covering of epidermis
‣ Epidermis (Upper and Lower)
‣ Mesophyll: Columnar and Spongey
‣ Veins (Vascular Structure) —> Vascular tissues
• Xylem (Larger): Carries around water
• Phloem (Smaller): Carries around Nutrients
‣ Stomata & Guard Cells
‣ Stomata & Guard Cells
• Guard Cells control what gasses can come into the leaf
Guard Cells rely on a “solute” concentration to determine wether or not they are opening/closing.
◦
Guard Cells rely on a “solute” concentration to determine wether or not they are opening/closing.
◦ Solute: Something that is dissolved in water
‣ Largely use &
‣ This is “active transport” which requires the use of ATP
◦ Process of Osmosis:
◦ Process of Osmosis: Movement of Water across a semi-permeable membrane.
‣ Will want to move from high pressure to low pressure/concentrations.
Abscisic Acid (Hormone that tells the guard cells to pump out K and Cl so that they close rapidly).
•What is the definition of a Hormone:
Abscisic Acid (Hormone that tells the guard cells to pump out K and Cl so that they close rapidly).
• Hormone: Molecular signal that changes the physiology of target cells.
Homeostasis:
Homeostasis: Maintaining a constant internal environment.
◦ Claude Bernard
CAM Photosynthesis:
CAM Photosynthesis: Have Stomata Open During the Night, and closed during the day.
◦ Stores CO2 during the night, and uses it in photosynthesis during the day inside the plant, even though the stomata are closed
• Crassulacean Acid Metabolism
- Light Dependent Reaction:
- Light Dependent Reaction:A. Sun energy is used to strip away electrons from Water — giving us Oxygen, ATP, and NADPH
Water —-> Oxygen + ATP + NADPH
a. ATP and NADPH cannot be stored, because they are volatile
Calvin-Cycle: Citric Acid Cycle
Calvin-Cycle: Citric Acid Cycle
A. Takes CO2 and uses ATP/NADPH to make Sugars
RuBP = Ribulose 1-5 biphosphate
3PGA = 3-Phosphoglycerate
Rubisco = Ribulose Biphosphate Carboxylase
RuBP = Ribulose 1-5 biphosphate
3PGA = 3-Phosphoglycerate
Rubisco = Ribulose Biphosphate Carboxylase
PEP (3 Carbon) + CO2 (1 carbon) ——> Pep Carboxylase Catalyst ——-> 4 Carbon Organic Acid
4C plants this occurs in?
PEP (3 Carbon) + CO2 (1 carbon) ——> Pep Carboxylase Catalyst ——-> 4 Carbon Organic Acid
In 4C plants, this reaction occurs in the mesophyll cell, then the spare carbon is pushed into the bundle sheath cell.
Photo Respiration:
RuBP (5 Carbon) + O2 (0 carbon) ——> Rubisco Catalyst ——> 1 PGA (3 Carbon Molecule) + 1 Glycolate (2 carbon molecule).
Xylem:
Xylem: Transports water and Nutrients from the roots to the shoots
Phloem:
Phloem: Transports Carbohydrates and Sugars around the plant “From source to Sink”
Cotyledon:
Cotyledon: Seed Leaf
What is the Name of the Vascular Bundle in these different Organisms?
Dicots:
Monocots:
Dicots: Vascular Bundle
Monocots: Atactosteele.
Xylem:
What is the 1st wall made from?
What is the second wall made from?
What do pits allow inside of the vessels, what does it prevent from entering?
Xylem:
1st Cell wall is made out of Cellulose
2nd Cell Wall, which is made out of Lignin
◦ Pits: Openings that allow water into the Cell Wall, but prevents air from entering
2 Main Types of Xylem
T_________ + V________ E______
2 Main Types of Xylem
- Tracheids:
A. Very long, and very thin
B. Cell is already dead. - Vessel Elements (500 Microns Wide).
A. Transports water much faster
B. Thicker, Shorter, and Fatter —- but they have a tendency to hook onto other vessel elements around them.
C. Lack an end wall
a. Creates a vessel — which is composed of many different vessel elements.
Transpiration:
Transpiration: The Loss of Water Vapor From leaves
• The movement of water, through Xylem — all the way out through the stomata.
Phloem:
Phloem:
‣ Transports Phloem Sap
• Largely filled with Sucrose, and other nutrients
Translocation
Movement of Phloem Sap from a Source into the “Sink” through the Phloem
Transpiration
Movement of Water from the Roots up through the shoots - and out the Stoma of the leaves .
Parenchyma
Thin Walled, Unspecialized cells
How does the Phloem Flow?
Phloem flows from: “The Source, to the Sink”
Rhizosphere:
Rhizosphere: Community of Bacteria and Fungi that lives in the soil. They have a symbiotic relationship with plants.
Casparian Strip:
◦ Casparian Strip - Layer of Hydrophobic Material (in the endodermis) that prevents selected molecules from entering, instead it forces materials to go through the Endo-membrane
Stele:
Stele = Vascular Tissue (Phloem and Xylem)
• Mycorrhizae: Symbiotic Relationship between a plant and a fungus
‣Explain the Difference of the two following types: ◦ Ectomycorrhizae ◦ Endomycorrhizae:
• Mycorrhizae: Symbiotic Relationship between a plant and a fungus
◦ Ectomycorrhizae ‣ Fungal strands extend outwards from the root. They don’t penetrate into the root cells, Carbon and nutrients are exchanged through the plasma membrane. ◦ Endomycorrhizae: ‣ Forms Arbuscules within the Cell -which are essentially spots with really high diffusion and exchange within the Root Cortex. ‣ Fungal cells penetrate inside of the root cells, enhancing exchange of nutrients and carbon
Nodes
Area on a stem where leaf buds are located
Internode
Space between Nodes
Meristem:
Meristem: Composed of “Totipotent” cells that can specialize into any purpose.
At the top of each branch, the ___ covers the meristem, offering it protection
Answer: Leaf Primordia
Flower Development:
Flower Development:
A Hormone (Florigen) specializes the leaf meristem and turns it into a “floral” Meristem.
After it’s transformed into a floral meristem, the flowers can start to grow from it.
◦ What does Florigen do?
◦ Florigen = Hormone that tells a leaf meristem to specialize and grow into floral meristems.
Homeotic Genes in flowers: A, B, and C.
What purpose do these 3 genes have?
Homeotic Genes in flowers: A, B, and C.
• Tells which cells to express which genes, so that they can develop into a specified part of the flower.
• Controlls differentiation
• Hormone:
• Hormone: Chemical signal that influences the Physiology and Development of a target cell.
Example #1: Auxin & Shoot Development:
Example #1: Auxin & Shoot Development:
• Auxin guides Vascular Differentiation so that the newly developing shoots become precursor to vascular tissue (procambium).
• Moves through Polar Transport. ‘
◦ Auxin can flow through the PIN Transport proteins, which are only on the Basal side of the cell. So the Auxin must flow from top to bottom - no other way.
‣ Polar Integral Network
• Cell Wall Extensibility: Tells the cells to get long & Thin = Pro-cambium Cells, which are precursors for Xylem and Phloem.
Example #2: Gibberelic Acid & Dwarf Plants.
Example #2: Gibberelic Acid & Dwarf Plants.
• Length of the stem is controlled by Gibberelic Acid.
• High Giberellic Acid = Large internode space, taller plants.
• Little Giberellic Acid = little internode space, shorter plants.
Example #3: Branching —> Auxin & Cytokinins
Example #3: Branching —> Auxin & Cytokinins
Apical meristem produces Auxin, which suppresses the growth of the Axillary buds. However, if the apical bud is removed — the axillary buds will start to bloom.
• Apical Dominance: Apical Meristem is dominant to the Axillary buds.
◦ Auxin is the hormone that suppresses the growth of axillary buds.
Cytokinins: Hormones that cause auxiliary buds to start growing, increasing rate of cell division.
Auxins:
Auxins: Hormone produced by Apical Meristem that inhibits the production of Cytokinins, thus suppressing the growth of Axillary buds.
Cytokinins:
Cytokinins: Hormones that cause auxiliary buds to start growing, increasing rate of cell division.
Example #4: Ethylene
Example #4: Ethylene
• Has an affect on fruit ripening. Helps the fruit to ripen.
◦ If you were to pump Ethylene onto unrippened fruits in a sealed space, they would ripen very quickly
Primary Growth Vs Secondary Growth
Primary Growth: Growing Taller
• Controlled by Apical Meristem
Secondary Growth: Increase in the Diameter of the plant (girth, width).
• Woody Vs Herbaceous Plants
Vascular Cambium
‣ Vascular Cambium: Makes Xylem and Phloem (Vascular Tissue).
Growth Rings
Growth Rings:
• Dendrochronology: Profession that looks at tree rings to determine how old they are.
◦ Distance between rings tells you how much the tree was able to grow that year.
Cork Cambium:
Cork Cambium: Produces (cork) a protective layer, outside of the plant.
Cork Produces Suberin:
Cork Produces Suberin: Which is a waxy material that is produced in cork cells that are stacked together like sand bags outside.
◦ Heartwood:
◦ Heartwood: Old Xylem will be filled with resin is called “heartwood”
Sapwood:
Sapwood is Xylem that is still being used for water transport
Plasmogomy:
Plasmogomy: Fusion of cytoplasms of fungi
Heterokaryotic:
Heterokaryotic: Unfused Nuclei from different parents
Karyogomy:
Karyogomy: Fusion of Nuclei in Heterokaryotic orgnamism
Glial cells (Helper cells):
Glial cells (Helper cells): Astrocytes, Schwann cells, olgiodendrocytes.
Pericycle function:
pericycle function: In roots, the pericycle is a unique tissue that it’s initiates the development of lateral roots
Animals:
Animals: Complex multicellular organisms that are heterotrophs.
• They are capable of moving.
• Animals lack a cell wall.
• Animals are capable of forming specialized tissues
Osmotic Pump:
Osmotic Pump: Maintains Turgor Pressure in a plant through semi-permeable membrane
