Chapter 3 Flashcards
Cell Structure
describe the shape of a plant’s cell wall
box-like/cuboidal/rectangular/isodiametric
a plant’s protoplasm contains what?
organelles like nuclei, mitochondria, chloroplasts
the physical framework within which a
plant’s metabolism occurs
cells
where is the energy of sunlight used to convert carbon dioxide and water to carbohydrates?
leaf cells
they perform many important tasks in cell metabolism
membranes
they regulate the passage of molecules into and out of cells and organelles; divide the cell into numerous compartments, each with its own specialized function; act as surfaces that hold enzymes
membranes
biological membranes are composed of what?
proteins and phospholipid bilayer
these are at least partially immersed in the lipid bilayer
intrinsic proteins
these proteins are located outside the membrane
extrinsic proteins
in this membrane composition, some proteins diffuse laterally and others are bound to adjacent proteins
fluid mosaic membrane
these can be bound to intrinsic proteins, converting them into glycoproteins
oligosaccharides
membrane “bubbles” that can carry materials with the cytoplasm
vesicles
two ways of transporting materials
exocytosis and endocytosis
this property of the membrane allows compartmentalization
permeability
they are found in domains Bacteria and
Archaea
prokaryotic cells
these contain a membrane-bound nucleus and organelles; found in plants, animals, fungi, and protists
eukaryotic cells
a mass of proteins, lipids, nucleic acids, and water within a cell
protoplasm
the selectively permeable membrane that covers the protoplasm
plasma membrane
this stores the genetic information of an organism
nucleus
the transport of materials to and from the nucleus is facilitated by “holes” in the nuclear envelope called
nuclear pores
the central vacuole has a single membrane called the?
tonoplast
this stores water, salts, crystals, starch, protein bodies, and other granules
central vacuole
is the site for cellular respiration
mitochondria
its inner membrane folds, forming cristae and increasing surface area
mitochondria
they have an inner and outer membrane and includes chloroplasts, and where diverse metabolisms take place
plastids
the inner fluids in plastids is called?
stroma
they are responsible for photosynthesis and contains chlorophyll
chloroplasts
when thylakoids stack up, they can form stacks of vesicles called?
grana
these are starch-storing plastids; occur in non-photosynthetic areas of the plants
amyloplasts
they store bright lipid pigments found in some fruits and flowers
chromoplasts
these are are large, unpigmented plastids involved in fat and lipid synthesis
leucoplasts
is a plant protein attached to stored iron that is almost exclusively stored in plastids
phytoferritin
this is the site for protein synthesis; aggregates of 3 molecules of rRNA and ~50 types of protein
ribosomes
is a system of narrow tubes and sheets of membrane within the cytoplasm; important in both manufacture and transport of molecules
endoplasmic reticulum (ER)
ribosomes are bound together by mRNA, forming a cluster called?
polysome
what are the two forms of ER?
smooth ER (involved in lipid synthesis and membrane assembly) and rough ER (covered with ribosomes)
are stacks of thin vesicles held together in an array that processes materials to be secreted
dictyosomes
have a forming face where ER vesicles accumulate, and maturing face where vesicles are released after content processing
dictyosomes
consists of all the cell membranes except for the inner membranes of mitochondria and plastids
endomembrane system
this is the clear substance of the cytoplasm and is composed of water, enzymes, and other chemicals
cytosol
are small, spherical bodies that isolate reactions that produce or use hydrogen peroxide
microbodies
these detoxify by-products of photosynthesis
peroxisomes
these are involved in converting stored fats into sugars
glyoxysomes
microtubules are structural elements of the cell that act as what?
cytoskeleton
the cytoskeleton is composed of two types of protein with a globally tertiary structure, namely:
alpha-tubulin and beta-tubulin
the long and flexible fibers in the cytoskeleton; thinnest part
microfilaments
microfilaments are composed of proteins called?
actin
is involved in structure and movement
starch is sometimes converted into (blank) and are stored as large oil droplets
lipids
name a few things plants store
crystals of calcium oxalate or calcium carbonate, silica, tannins, and phenols
not only provides strength and protection, but is also a site for metabolism
cell wall
a plant’s cell wall is primarily composed of?
cellulose, hemicellulose, and pectins
parallel cellulose crystallize into (blank), which cover the plasma membrane
microfibrils
describe a plant’s primary cell wall
thin
what allows direct communication in plants?
plasmodesmata
these are small channels that connect adjacent cells
plasmodesmata
clustered occurrences of streams of cystol and section of the ER in the plasmodesmata is called?
primary pit fields
areas in the walls of plant cells where the primary walls of adjacent cells are very thin, and plasmodesmata are present in high density
this connects the protoplast to create the symplast
plasmodesmata
All intercellular space and cell walls together called the?
apoplast
what route does the apoplastic pathway take?
through the cell wall
what route does the symplastic pathway take?
through the cytoplasm
