Exam 1 Flashcards
Vascular tissue system
Function: conduction of water, nutrients, sugars, and hormones throughout the plant.
Tissues: xylem- conducts water and nutrients up roots, stems and leaves.
Phloem- conducts water, sugars, hormones, etc. down and up roots, stems and leaves; moves from where produced (called sources) to where needed (called sinks).
Dermal tissue system
Function: protection from the environment
Tissues: epidermis- single layer of cells on primary (herbaceous) plant parts.
Periderm or bark - corky tissue that replaces epidermis on secondary (woody) plant parts
Ground or fundamental tissue system
Function: storage. Support. Filler tissue and site of photosynthesis
Tissues: cortex- outer region of stems and roots
Pith- center of stems
Mesophyll- middle of leaves and flower pedals
What are the three basic cell types that compromise most of the tissue of plants?
Parenchyma
Collenchyma
Sclerenchyma
What is the parenchyma?
- thin non-lignified primary cell walls
- filler. Storage, protection, photosynthesis
- ex: flesh of potato, lettuce leaf.
- isodiametric
What is the collenchyma?
- unevenly thickened, non-lignified primary cell walls
- support in growing tissues
- ex: strings in celery stalks
- longer than wide
What are the two types of sclerenchyma?
Fiber(bamboo cane): Long slender and pointed on ends
Sclereid(seed coat) or stone wall(pear fruit): multi shaped or columnar.
What is sclerenchyma?
Evenly thickened , lignified (tough), secondary cell walls. Dead at maturity.
What is the cell wall?
Primary: herbaceous tissue,
Secondary: lignified tissue
What is a polysaccharide?
A polymer or chain of sugars
What are the three polysaccharides?
Cellulose: forms a matrix of microfibrils( chains of beta-1, 4-linked glucose)
Hemicellulose: filler between cellulose microfibrils (chain of misc. sugars)
Pectin: cementing agent or filler; high middle lamella and fruit;(chains of gala turnip acid)
What is lignin?
Tough polymer of phenolic compounds; high in secondary cell wall
What is protein?
Mainly structural (most commonly hydroxyproline) A polymer or chain of amino acids
What are the components of a cell wall?
Polysaccharide
Lignin
Protein
What is plasmalemma or plasma membrane?
The membrane that surrounds the cytoplasm; composed of a bilayer of phospholipids and proteins; its selectively permeable and regulates absorption into cells and leakage from cells.
What is plasmodesmata?
Tubular plasma membrane extensions through cell walls; connect adjacent cells
What is cytoplasm?
Cytosol plus organelles; most metabolism occurs in the cytosol or the organelles
What are the two components of cytoplasm?
Cytosol
Organelles
What is cytosol ?
Fluid portion of the cytoplasm ; a solution of dissolved/suspended compounds
What are organelles?
Specialized structures in cytoplasm, each with specific functions
What are the components of an organelle?
Nucleus:location of DNA and some RNA
Mitochondrion:major site of respiration, called the power house of the cell
Plastid: double membrane bound bodies for storage and photosynthesis
Endoplasmic reticulum: tubular membranes for communication across the cytoplasm ; site of protein and membrane synthesis
Ribosome: dense spheres of RNA ; protein synthesis occurs on their surface
Vacuole: storage of organic acids, salts, anthocyanins(blue, red, purple pigments), metabolic wastes, enzymes and metabolites
Golgibody or dictyosome:disk shaped membranes for membrane and polysaccharide synthesis
Micro body: membrane bound storage bodies with various functions
Microtubule: tubular rods used in mitosis and cellulose orientation in cell walls
What are the components of plastic?
Leucoplast: colorless plastids. There are two, amyloplast(starch storage with chains of sigma-1’ 4-linked glucose). The second is elaioplast (fat and oil storage)
Chromoplast: colored plastids for storage of carotenoids( Orange and yellow pigments)
Chloroplast: green plastids that contain chlorophyll; the site of photosynthesis
What are the components of a vacuole?
Tonoplasts: membrane that surrounds the vacuole
Define DNA?
Deoxyribonucleic acid. A double helix chain of sugar- phosphates(deoxyribo sugar phosphates) connected by nucleic acids ( adenine, thymine, guanine, cytosine)
Define RNA
Ribonucleic acid. A single stranded chain of sugar phosphates(ribo sugar phosphates) containing nucleic acids (adenine, uracil, guanine, cytosine)
What are nucleic acids?
Organic acids that form base pairs of DNA and single based RNA
What are the base pairing of nucleic acids between the double strands of DNA
A-T (adenine, thymine)
G-C (guanine, cytosine)
What are the base pairing of nucleic acids between DNA strands and RNA strands?
A-U (adenine, uracil
G-C (guanine, cytosine
Define gene.
Length of DNA that codes for the production of a protein or protein sub unit.
Also codes for active RNA (such as tRNA)
What is an enzyme?
A protein that acts as a metabolic catalyst
How do plants grow?
Plants grow from localized areas called the meristem.
What is the meristem?
Discrete regions or groups of cells that posses continued cell division for the life of the plant or that organ.
What types of growth do pants experience?
Primary Growth and Secondary Growth.
What is primary growth?
Growth in LENGTH that gives rise to primary (herbaceous) tissues called the primary plant body.
What 2 types of meristems give rise to primary growth?
Apical meristem or apex: the growing points located at the tips of stems and roots
Intercalary meristem: the growth region at the base of grass leaves that causes leaves to elongate.
What is secondary growth?
Growth in WIDTH or DIAMETER that gives rise to secondary (woody or corky) tissue called the secondary plant body
-Lateral meristem: meristematic regions along the sides of stems and roots
What are the 2 types of lateral meristems that give rise to secondary growth?
Vascular cambium or cambium: a sheet-like meristem between the bark and wood along the sides of woody stems and roots; it gives rise to secondary xylem (wood) on the inside and secondary phloem on the outside.
Cork cambium or phellogen: gives rise to periderm (bark)
What are the characteristics of monocots?
Leaves: Linear; leaf base or petiole sheathing, parallel venation
Growth Habit: Herbaceous to woody, no true wood
General appearance: grass like leaves. Long and linear
What are the characteristics of dicots?
Leaves: Broad; petiole present, net venation
Growth Habit:; Herbaceous or woody
General Appearance: Broad leaves like lettuce, the typical trees outside.
What are the characteristics of gymnosperms?
Leaves: needle like, or scale like.
Growth habits: Herbaceous or woody
General appearance: needle like, pine trees or christmas trees
What are the components of stem morphology?
terminal bud axillary or lateral bud flower bud leaf scar internode node lenitcel growth rings
What is the terminal bud?
a bud at the tip of a stem responsible for terminal growth
What is a bud?
an underdeveloped and elongated stem composed of a short axis with compressed internodes, a meristematic apex, and primoridal leave and/or flowers.
What is an axillary bud or lateral bud?
buds along side the axis of a stem; they were produced by the terminal bud during growth; once they grow out and form a lateral stem they become terminal buds of the lateral branch
Define flower bud.
a bud with a floral meristem that develops into flowers; usually larger than vegetative buds
Define leaf scar.
a scar marking the former point of attachment of a leaf or petiole to the stem
Define internode.
the part of the stem between two nodes
What is a node?
part of the stem marking the point of attachment of leaves, flowers, fruits, buds and other stems
What is a lenticel?
rough areas on stems composed of loosely packed cells extending from the cortex through the ruptured epidermis; serve as “breathing pores” for gas exchange, and only in young stems
What are growth rings?
bud scale scars from the last terminal bud; they denote flushes of growth. Can be used to age stem because one growth ring is usually produced per yer on temperate trees native to the Temperate Climate Zone
