Mastering biology chp 6
Microfilaments are responsible for ___ and the cell's ___
cell locomotion;structural characteristics.
solution inside the central vacuole which is the plants main repository of inorganic ions including potassium and chloride
cell sap
strong protective structure made from cellulose fibrils
cell wall
micrtubules are also required for __ via __ and __
cellular locomotion via flagella and cilia.
what are cell walls made out of
cellulose fibrils
what are some organelles that are only in animal cells
centriole
Any unincorporated radioactively labeled amino acids are washed away and large amounts of the same, but unlabeled, amino acid are added.
chase phase
chloroplasts contain the green pigment ___
chlorophyll.
They are the sites of reactions that convert solar energy into chemical energy.
chloroplast
makes sugar by converting light energy into chemical energy
chloroplast
what are some organelles that are only in plant cells
chloroplast, cellulose cell wall, central vacuole
The _____ is composed of DNA and protein.
chromatin
The __ of a eukaryotic cell plays a major role in organizing the structures and activities of the cell.
cytoskeleton
provides the cell with structural support?
cytoskeleton
most of the proteins made by free ribosomes function within the
cytosol
where are ribosomes located (2)
cytosol and rough ER
free ribosomes are suspended in the __ and bound ribosomes are attached to the outside of the __ or ___
cytosol, endoplasmic reticulum or nuclear envelope
Most proteins made by free ribosomes function in the
cytosol.
The prefix "lyso-" means
decomposition
bound ribosomes generally make proteins that are __ (3)
destined for insertion into membranes, packaging within certain organelles such as lysosomes, or export from the cell
. Many cell organelles, most notably the nucleus, are anchored by ___ which are assembled from a diverse class of proteins.
intermediate filaments
The only cytoskeletal fibers not associated with intracellular movement or whole cell locomotion are the ___.
intermediate filaments
what are the two internal compartments that the inner membrane divides mitochondrion into
intermembrane space and mitochondrial matrix
the narrow region between the inner and outer membranes
intermembrane space of mitochondria
the membranes of the chloroplasts divide the chloroplasts space into three compartments
intermembrane space, stroma, and thylakoid space
what are three functions of the smooth ER
lipid synthesis,poison detoxification,calcium ion storage
what are some organelles that are in plant and animal cells
mitochondrion,endoplasmic reticulum,Golgi apparatus,plasma membrane,nucleus,cytoskeleton
what is the function of the golgi appartus
modifies and packages proteins
double membrane that encloses the nucleus
nuclear envelope
Proteins made by bound ribosomes either function __ or __
within the endomembrane system or pass through it and are secreted from the cell.
how do central vacuoles in plant cells develop
smaller vacuoles merge
what is the relative size of ribosomes
25 nm
how many endoplasmic reticulum are in a cell
2; rough and smooth
what is the size of chloroplasts
3-6 um
Which statements are true for chloroplasts? Select the three that apply. A.They have membranous sacs called thylakoids that are surrounded by a fluid called stroma. B.Their matrix contains enzymes that function in cellular respiration. C.They are the sites of reactions that convert solar energy into chemical energy. D.Their inner membrane has infoldings called cristae. E.They contain the green pigment chlorophyll. F.They are the sites of reactions that convert chemical energy from food molecules to ATP.
A, C, E
can be used to separate different organelles to study their function separate from the rest of the cell.
Cell fractionation
a membranous system of interconnected tubulues and flattened sacs called cisternae. continuous with the nuclear envelope
ER
internal compartment of the ER
ER lumen
Which of the following proteins are synthesized by bound ribosomes? Select all that apply. View Available Hint(s) Select all that apply. DNA polymerase lysosomal enzyme ER protein ribosomal protein insulin actin
ER protein, lysosomal protein, and insulin
transport vesicle carries proteins from the __ to the __ for secretion
Golgi to the plasma membrane
are rope-like structures that anchor organelles and intercellular junctions called desmosomes. They are specialized for bearing tension.
Intermediate filaments
serve as intracellular highways for transporting vesicles and organelles; they are also required for cellular locomotion via flagella and cilia.
Microtubules
is the first of the two main steps of protein synthesis.
Transcription
Most proteins that function in the cytosol (such as ___) or in the nucleus (such as ____) are synthesized by free ribosomes
actin, DNA Polymerase
a damaged organelle or small amount of cytosol becomes surrounded by a double membrane and a lysosome fuses with the outer membrane of this vesicle
autophagy
the recycling of the cells own organic material
autophagy
what are 2 functions of lysosomes
autophagy , macromolecule digestion
Only __ and __ have prokaryotic cells, which lack a nucleus and other membrane-enclosed organelles.
bacteria and archaea
_____ is/are identical in structure to centrioles.
basal bodies
Intermediate filaments are specilized for
bearing tension
cells that specialize in protein secretion (the cells of the pancreas that specialize in protein secretion ) frequently have a high portion of
bound ribosomes
Proteins that function within the endomembrane system (such as lysosomal enzymes) or those that are destined for secretion from the cell (such as insulin) are synthesized by
bound ribosomes.
Eukaryotic cells have an integrated network of organelles, including the___(3)which is collectively referred to as the endomembrane system.
endoplasmic reticulum (ER), the Golgi apparatus, and lysosomes,
what are examples of proteins made by free ribosomes
enzymes that catalyze the first steps of sugar breakdown
the mitochondrial matrix contains many different __ as well as the __ and ___
enzymes; mitochondrial DNA and ribosomes
As a protein destined for the endomembrane system is being synthesized by a ribosome, the____ in the growing polypeptide chain act as a signal sequence.
first amino acids
Most proteins that function in the cytosol (such as actin) or in the nucleus (such as DNA polymerase) are synthesized by
free ribosomes.
during phagocytosis, lysosomes -__
fuse with food vacuoles and hydrolytic enzymes digest food particles
during autophagy, lysosomes
fuse with vesicles containing damaged organelles and hydrolytic enzymes digest organelle components
the plasma membrane expands by ___ and proteins are secreted from the cell
fusion of vesicles;
the main functions of lysosomes are to __ (3)
get rid of viruses and bacteria, digest food particles and other damaged organelles, and help patch cell wall membranes
what is the importance of cristae
give the inner membrane a large surface area. enhancing the productivity of cellular respiration
The ___ modifies, stores, and packages products of the ER.
golgi apparatus
thylakoids are stacked like poker chips ; each stack is called a ___
granum
the central vacuole plays a major role in
growth of plant cells
lysosomes contain active ___
hydrolytic enzymes
enzymes that make ATP are built into the _ of mitochondria
inner membrane
Where is calcium stored?
smooth ER
As they are being synthesized, secretory proteins enter the ___of the endoplasmic reticulum. From the ER, vesicles transport these proteins to the Golgi, where they are sequentially modified and concentrated in a___
lumen, cis-to-trans direction.
Proteins that function within the endomembrane system (such as ___) or those that are destined for secretion from the cell (such as ___) are synthesized by bound ribosomes.
lysosomal enzymes, insulin
Which organelle plays a role in intracellular digestion?
lysosome
what is the function of contractile vacuoles
maintain a suitable concentration of ions and molecules inside the cell
During muscle contractions, myosin motor proteins move across tracks of ___.
microfilaments
the extension of psuedopodia in amoeba is due to the regulated assembly and destruction of ___.
microfilaments
The cytoskeleton consists of what three main types of fibers
microfilaments, intermediate filaments, and microtubules.
Centrosomes are sites where protein dimers assemble into ___.
microtubules
In eukaryotic flagella, the fibers that slide past one another due to the activity of dynein proteins are ___.
microtubules
Which of these are hollow rods that shape and support the cell?
microtubules
Which of these organelles carries out cellular respiration?
mitochondria
produces chemical energy (ATP) that can power the cell
mitochondria
what are some organelles only in prokaryotic cells
nucleoid
Ribosomal subunits are manufactured by the _____.
nucleolus
what are some organelles only in eukaryotic cells
nucleolus,lysosome,mitochondria
The___ contains most of a cell's DNA
nucleus
Which of these organelles produces H2O2 as a by-product?
peroxisome
how are food vacuole formed
phagocytosis
each of the two membranes enclosing the mitochondrion are __ with a collection of embedded __
phospholipid bilayer/ proteins
The _____ is a selective barrier, regulating the passage of material into and out of the cell.
plasma membrane
what are some organelles in both prokaryotic and eukaryotic cells
plasma membrane,ribosomes,flagella
__ cells are smaller and, at the level of the individual cell, are generally less versatile than ___ cells, which compartmentalize many of their metabolic pathways into organelles
pro, euk
__ are indispensable in every known ecosystem, and certain species are capable of surviving in some of the harshest and most nutrient-limiting environments on Earth.
prokaryotic
what are 2 functions of the golgi apparatus
protein modification and sorting cisternal maturation
what is the main function of the rough ER
protein synthesis
The endomembrane system serves a variety of functions within the cell, including___( 3)
protein synthesis and transport, metabolism of lipids, and detoxification.
what is the order of the pathway of secretory proteins through the endomembrane system in Eukaryotic cells
protein synthesis->endoplasmic reticulum-> cis golgi cisternae->medial golgi cisternae ->trans golgi cisternae->plasma membrane ->extracellular space
Cells are exposed to a high concentration of a radioactively labeled amino acid for a short period to tag proteins that are being synthesized.
pulse phase
what two things do pulse- chase experiment include
pulse phase and chase phase
Scientists can track the movement of proteins through the endomembrane system using an approach known as a
pulse-chase experiment.
how do contractile vacuoles maintain a suitable concentration of ions and molecules inside the cell
pump excess water out of the cell
what are some functions of the central vacuole (3)
regulates cytoplasm composition, creates internal pressure, and stores cell compounds
As a protein destined for the endomembrane system is being synthesized by a ribosome, the first amino acids in the growing polypeptide chain act as a signal sequence. That signal sequence ensures that the __ and that the ___
ribosome binds to the outer membrane of the ER and that the protein enters the ER lumen.
_____ are the sites of protein synthesis.
ribosomes
All proteins are synthesized by
ribosomes in the cell.
Which of these organelles manufactures proteins bound for secretion out of the cell?
rough ER
the nuclear envelope is connected to the __, which is also continuous with the ___
rough er, smooth er
the outer membrane of the mitrochondrion is ___ , the inner membrane is ___
smooth, twisted with infoldings called cristae
what is the number of mitochondria in a cell? (2)
some cells have one large mitochondrion but more often a cell has hundred or even thousands of mitochondria
what is the structure of peroxisomes
spherical, often have granular or crystalline core, single membrane, contain enzymes
the fluid outside the thylakoids that contains the chloroplasts DNA , ribosomes, and enzymes
stroma
pinches off transport vesicles and other vesicles that give rise to lysosomes and vacuoles
the golgi
what is a common trait of mitochondria and chloroplasts
they both have their own DNA and ribosomes
inside the chloroplasts is a membranous system in the form of flattened, interconnected sacs called ___.
thylakoids
chloroplast have membranous sacs called ___that are surrounded by a fluid called ___
thylakoids , stroma
Beginning within the nucleus, the first step leading to the synthesis of a polypeptide is _____. A. translation of an RNA nucleotide sequence into a sequence of amino acids B.removal of introns from RNA and the stitching together of exons C.linking of nucleotides to form a polypeptide D.transferring of information from DNA to messenger RNA E. translation of a DNA nucleotide sequence into a sequence of amino acids
transferring of information from DNA to messenger RNA
membranes and proteins produced by the ER move via __ to the __
transport vesicles to the golgi
