Chapter 3: Plant Cells Flashcards
Chloroplasts
organelles in plant cells responsible for photosynthesis
Stroma
enzymes for light independent reactions of photosynthesis
Which organelle are stroma found in?
chloroplasts
Grana
stacks of thylakoid membrane
membrane embedded with cholrophyll, proteins, and other photosynthetic pigments
Which organelle are grana found in?
chloroplasts
Oil bodies
store oils in chloroplasts
Starch droplets
store starch in chloroplasts
circular DNA (cpDNA)
resemble bacterial DNA in chloroplasts
Which organelle are ribosomes found in?
chloroplasts
Where are chloroplasts located?
mesophyll (middle) of green leaves
Chromoplasts
pigments other than chlorophyll
colours in fruits and flowers
Leukoplasts
lack colour
common in epidermal/storage tissues
Amyloplasts
Leukoplast
synthesizes starches
Etioplasta
dark chloroplasts
convert to chloropalsts when exposed to light
Vacuoles
membrane bound organelles that store water, food, waste, and other materials
Tonoplasts
membrane surrounding cells
Which organelle are tonoplasts found in?
vacuoles
Cell sap
composition of water, inorganic ions, sugars, organic acids, amino acids, and pigments
Cell sap of the vacuole has what property?
hypertonicity
Hypertonicity
inside of the cell compared to the outside has a higher solute concentration
What is the function of hypertonicity?
increases Turgor pressure to maintain plant structure; “solutes suck”
What are the three components of the cell wall?
-middle lamellae
-primary cell wall
-secondary cell wall
Which component of the cell wall is laid down first?
Middle lamellae
What is the function of the middle lamellae?
-connects cell walls to cell walls
-extensible/expandable
What is the middle lamellae made of?
pectins
Primary cell wall
innermost wall
What is the composition of the primary cell wall?
cellulose, pectin, hemicellulose, glycoproteins
Primary pit fields
thinner portions of cell wall with no secondary wall on top
Plasmodesmata
openings between adjacent cells, allowing for cytoplasmic continuity
Desmotubules
strands of ER stuck through plasmodesmata
allows for cytoplasmic continuity
Pit membrane
contains primary cell wall and middle lamellae
Simple pit pair
secondary cell wall does not overhang put membrane
Bordered pit pair
secondary cell wall overhangs pit membrane
What is the composition of the secondary cell wall?
cellulose, hemicellulose
little to know pectin or glycoproteins
Describe the makeup of the secondary cell wall.
Three different layers laid in different orientations to increase strength
Is secondary cell wall present over pit fields?
No
What component may be found in the secondary cell wall?
Waxes
What is a phragmoplast?
collection of microtubules that guide vesicles from the Golgi
When does the phragmoplast form?
early telophase
What is the function of a phragmoplast?
directs cell wall components to form cell plate proteins
