Unit Two: Dr Smith's Content Flashcards
What are Flagella and Cilia
- elongated motile structures that extend from cell surface
- cilia are shorter than flagella
- cilia have a greater amount
- flagellnum propel prokaryotic cells to move
What are some structure relevant to plant cells
- chloroplasts
- central vacuole
- plant cell walls
What are Plastids
- yellow-green in colour
- site of photosynthesis in plant cells
- plastids contain DNA genomes and machinery for gene expression + synthesis of protein on ribosomes
- some proteins within plastids are encoded by genomes/nuclear genes and imported into organelles from cytosol
What are Chloroplasts
- surrounded by outer membrane and inner memebrane in the stroma
- thykaloid content
- thykaloids contain chlorphyll
- CONVERT LIGHT ENERGY
What is the Central Vacuole
- large vesicles that perform specialized
- 90% or more of plant cells can be made up of central vacole
- tonoplast: surrounds the central vacuole
What are the functions of central vacuoles
- supports the cell structure
- store salts, organic acid, sugars, storage proteins, pigments and waste products
- produce colours of many flowers
- contain enzymes that break down molecules
- contain molecules that provide chemical defences against pathogenic organisms
What is the function of the Cell Wall
- support individual cells
- protect cells against invading bacteria and fungi
- contribute to turgor pressure produced in central vacolue
- consist of cellulose
What is Cellulose
- long polymers of glucose
- most abundunt macromolecule
- aggregate into bundles (microfibrils)
- embedded into network of other polysacchardies
What does the middle lamella do
also known as (pectin)
hold together walls of adjacent cells
What is the Plasmodesmta
- plasma membrane lined-channels that connect the cytosols of adjacent cells
- allow ions and small molecules to move directly from one cell to another through cytosol
What does the Plasmodesmta do
preforate primary and secondary cell walls
What are some specialized animal structures
- Cell adhesion molecules
- Cell Junctions
- Extracellular Matrix
What are Cell Adhesion Molecules
- glycoproteins in plasma membrane that bind to specific molecules on other cells
- organize animal cells into tissues and organs
- provide avenues of communication
What are Anchoring Cell Junctions
- form buttonlike spots, belts, that run entirely around cells
- welding adjacent cells together
most common in tissues subjected to stretching, scarring, shear, etc
What are Desosomes
Anchoring Cell Junction
anchoring junctions with intermediate filaments that anchor junction in underlying cytoplasm
What are Adherns Junctions
Anchoring Cell Junction
anchoring junctions with microfilaments as the anchoring cytoskeletal component
What are Tight Cell Junctions
- regions of tight connections between membranes of adjacent cells
- seal spaces between cells that cover internal organs, outer surface of body, lining of internal cavities and cuts
- formed by direct fusion of proteins on outer surface
What are Gap Junctions
- open direct channels that allow ions and small molecules to pass directly from one cell to another
- communicate between cells within a tissue
What is the Extracellular Matrix (ECM)
- animal cells are embedded in ECM
- consits of proteins and polysaccharides secreted by cells
- forms mass of skin, bones, tendons
- provides protection and support
- affects cell division, adhesion, takes part in wound reaction
Where is the ECM both HARD and SOFT
SOFT: cartilage (containing high linkage of glycoproteins)
HARD: bone (containing mineral crystals)
What is the Cytoskeletion
- helps cells to maintain shape and internal organization
- support to carry out cell function
Components of the Cytoskeleton
- Intermediate Filaments
- Microtubules
- Actin Filaments
What are Peroxisome
- single membrane organelles
- sequester diverse oxidative reactions
- play important roles in metabolism, oxygen detoxification, and signaling
- catalyze reactions, reduce oxygen
