Cells Flashcards
Cell shape
can range in size
Immature and parenchyma
spherical
mature
faceted then cylindrical
14 facets where it is contacting other cells
Primary cell wall
- pectin (jelly)
- cellulose (polymers, most abundant on earth)
- hemicellulose (forms cross links in cellulose fibers
- glycoproteins
- plasmodesmata
secondary cell wall
tougher
has everything from the primary cell wall
has lignin… celluloseand hemicellulose
strong tough waterproof wall
the nucleus
- nuclear envelope ( pores control the flow of things in and out)
- nucleolus (assembled in nucleus, proteins/rna… build ribosomes)
- chromatin (in cytoplsm)
- nucleoplasm
ER
rough and smooth
rough = cytoprotein synthesis
smooth = lipid secretion and packaging
dictyosomes
a few different types.
stacks of disk-like membranes
similar to the structure of golgi apparatus
function is to modify glycoproteins that were assembled in ER, pack things in vesicles to send then out (can be oil or nectar)
dictyosomes are what makes flowers smell good (exporting materials)
ribosomes
rna and proteins
Plastids
Unique to plants, multiple types of plastids.
They are a double membrane organelle that contains chloroplasts.
Chloroplasts
In plastids, scattered in cytoplasm
contains stroma, which is a liquid.
Also contains Grana, which are interconnected thylakoids. This is where photosynthesis takes place! (Surface of Grana)
stroma
Inside chloroplast
contains liquid, oil droplets, starch grains, enzymes.
Where the small circular dna of chloroplasts are located, as well as their ribosomes.
One of these enzymes are RuBP carboxylase
chromoplasts
chromo = color.
Can fill with carotenoids, to make the bright colors. Carrots tomatoes and peppers have many chromoplasts.
Red petals are cause by anthocyanins
Leucoplasts
colorless
two types:
Amyloplasts synthesizes and store starch
Elaioplasts: synthesizes and stores oil
Tannosomes
new, made from chloroplasts…
Pieces of broken thylakoid membrane forms globs called pearling, secreted through cell and injected into central vacuole. During this process become filled with tannin compounds (destroys proteins). Remain in vacuole
microbodies
small spherical, single membrane bound organelle
examples are peroxisomes (makes peroxide) contains enzymes for dealing with photorespiration and chopping FA that releases peroxide.
Glyoxisomes: convert fat to carbohhydrates..
Lysosomes (which are in animal cells, NOT IN PLANTS)
Lipid, oil, wax droplets
Vacuole parts
Tonoplast, cell sap
Tonoplast in vacuole
Contain liquid called the cell sap. This is where pressure is maintained for osmosis.
Cell sap is slightly acidic, much like a “dumping ground”. Acid from things broken down, sugar, organic acids, proteins water soluble pigments
Ex: Black dahlia has a high concentration of anthocyanins in tonoplast s
vacuole function
store cell material
Cytoskeleton
Contain microtubules and micro filaments… contain a network
Microtubule: Can find them in the plasma membrane
Microfilaments: smaller, around 6 nm in diameter, involved in cytoplasmic streaming
Interphase
G1… growth of Gap 1. Chromosomes are not condensed , longest, cell grows in size, transcription and translation takes place, produces materials needed for S phase
S… synthesis
G2… Growth or Gap 2…. getting ready for next cell division. Mitochondria and plastids divide and set up.. chromosomes begin to condense
Mitosis
occurs in meristem tissue
1. Prophase.. no centrioles to anchor spindle fibers…
2. Metaphase… chromo line up in middle
3. Anaphase … chromo separate
4. Telophase… Microtubules called phragmoplasts (diff from spindle fibers), but from newly forming nuclei, dictyosomes involved (How are they involved)?, pectin and cellulose are directed to the the center line to build a cell wall. Fuse together to form a cell plate, which grows until the two cells are divided
