Ch 3. Cells LearnSmart
central vacuole in plants
contains enzymes, salts, pigments, sugars, and acids
the _____ is the fluid matrix between the cel membrane and the nucleus
cytoplasm
the _____ is the fluid matrix between the cell membrane and the nucleus
cytoplasm
the two-layered nuclear envelope separated the nucleus of a cell from the
cytoplasm
the two-layered nuclear envelope separates the nucleus of a cell from the
cytoplasm
what cell structure binds to mRNA coming from the nucleus and manufactures proteins?
ribosome
the nucleolus is a dense spot in the nucleus where components of _____ are assembled
ribosomes
select all of the following that are found in mitochondria
ribosomes, enzymes, DNA
proteins to be secreted outside of a eukaryotic cell are formed at ribosomes on the surface of the _____ endoplasmic reitculum
rough
proteins to be secreted outside of the eukaryotic cell are formed at ribosomes on the surface of the _____ endoplasmic reticulum
rough
select the true statement describing how DNA in the nucleus is used to specify protein production by the cell
DNA is copied into mRNA in the nucleus, and the mRNA is used outside the nucleus to make proteins
what is a network of sacs and tubules extending off the nuclear envelope where proteins and lipids are produced?
Endoplasmic reticulum
making a membrane protein
1. in the nucleus, genes in the DNA that encode the membrane protein are copied into a messenger RNA (mRNA). 2. the mRNA exits the nucleus through nuclear pores of the nuclear envelope 3. the mRNA binds to a ribosome of the rough ER and produces a protein, which exits the ER in a vesicle 4. the vesicle delivers the protein to the Golgi apparatus, where the protein folds and is packaged in the vesicle for export from the cell 5. the vesicle fuses with the cell membrane and releases the protein into the membrane surface
the _____ is a series of flattened sacs which sorts and packages materials into vesicles to be sent to the cell membrane
Golgi apparatus
select types of cells that have relatively more lysosomes
White blood cells and liver cells
select all of the following that are true about eukaryotic flagella
anchored by basal body, prominent in sperm cells, and contain microtubules
if an mRNA specifies a protein to be used in the cell membrane or to be secreted from the cell, this protein is made on ribosomes that
attach to the endoplasmic reticulum
enzymes in the Golgi apparatus can synthesize and attach _____ to proteins and lipids, forming glycoproteins and glycolipids
carbohydrates
what plant cell organelle can occupy up to 90% of the cell volume and can exert turgor pressure against the cell membrane when it acquires water?
central vacuole
each centrosome in animal cells contains two _____, which form basal bodies of flagella and cilia and spindle fibers of chromosomal division
centrioles
in animal cells, structures called _____ are microtubule-organizing centers that contain the centrioles
centrosomes
the organelle that is the site of photosynthesis in plant cells is the _____, which is a type of plastid
chloroplast
short, numerous, hairlike structures that surround some cells like a fringe, are powered by microtubules, and have coordinated movements are called
cilia
some protists, like Paramecium, are able to move through a watery environment with thousands of short extensions on the cell called _____
cilia
select all of the locomotory structures that consist of nine microtubule pairs surrounding two separate microtubules and connected by dynein protein
cilia and flagella
although both are involved in movement and arise from basal bodies of microtubules, _____ are short and numerous extensions, whereas _____ are longer and occur singly or in pairs
cilia; flagella
defective proteins, such as ankyrin and dystrophin, and impact injuries to brain cells can disrupt the normal structural support provided by the _____ and cause the cells to degenerate
cytoskeleton
in Duchenne muscular dystrophy, cells lack the protein dystrophin, which is a component of the _____ in muscle cells
cytoskeleton
three types of protein filaments (actin molecule, protein subunits, and tubulin subunits) comprise the _____, which is a network of proteins that provide a structural framework within the cell
cytoskeleton
what is the network of protein fibers and tubules inside the cell that provides support and aids in cell division and movement?
cytoskeleton
the _____ is a protein network that occurs within the cytoplasm that provides support and helps in _____
cytoskeleton; cell to cell connections
select all of the following that are true about peroxisomes
detoxifies H2O2, break down fatty acids, dismantle toxins from the blood, and internal proteins can condense into crystals
food vacuole in amoebas
digest nutrients engulfed by cell
the internal membrane of several organelles are interconnected and form the _____ system of a eukaryotic cell
endomembrane
peroxisomes are organelles that originate at the _____ and contain enzymes that dispose of toxic substances
endoplasmic reticulum
select the organelles that are involved in the production of milk proteins to be secreted by mammary gland cells in animals called mammals
endoplasmic reticulum, Golgi apparatus, nucleus
what theory describes how ancient organisms engulfed bacterial cells and, instead of being digested, the bacterial cells became organelles within the host cells?
endosymbiosis
what types of cells are likely to contain thousands of mitochondria
energy-consuming muscle cells
lysosomes are organelles that contain digestive _____ that break down food particles, old organelles, and other cellular debris
enzymes
select all of the following that are true about lysosomes
enzymes inside the lysosome perform hydrolysis reactions, contain enzmyes tagged with sugars, and can fuse with vesicle carrying debris from outside the cell or damaged organelles
what eukaryotic cellular extension is long, has a whiplike motion that propels cells, and usually occurs singly or in pairs?
flagellum
lysosomes originate from vesicles that bud from the _____, and the enzymes contained in lysosomes are synthesized in the _____
golgi apparatus; rough ER
cytoskeletal components called _____ filaments are made of different proteins depending upon the cell type and help to maintain cell shape and bind some cells together
intermediate
select all of the following that are found in the cytoplasm, outside the nuclear membrane
ions and enzymes, RNA and ribosomes, and cytoskeleton
cellular respiration extracts energy from food and takes place in the organelle called a(n) _____
mitochondrion
within the nucleus, protein synthesis information in DNA is copied into _____, which then exit the nucleus through nuclear pores
mRNA molecules
what type of cytoskeleton filament is shown in the picture? (actin molecule)
microfilament
cytoskeletal components called _____ are long, thin rods of actin protein that are used in muscle contractions, stretching and compression, and anchoring of cells
microfilaments
what type of cytoskeleton filament is shown in the picture? (tubulin subunits)
microtubule
which of the three main components of the cytoskeleton is composed of tubulin protein subunits and is used in cell division and transportation within cells
microtubules
which of the three main components of the cytoskeleton is composed of tubulin protein subunits and is used in cell division and transportation within cells?
microtubules
cellular respiration extracts energy from food and takes place in the organelles called a(n) _____
mitochondria
select the organelles that are thought to have arisen by endosymbiosis
mitochondria and chloroplasts
select all of the cell parts that are involved in the endomembrane system
nuclear envelope, lysosomes, Golgi apparatus, and endoplasmic reticulum
the _____ found within the nuclear envelope are lined with specialized proteins that allow the transport of substances into and out of the nucleus
nuclear pores
the _____ found within the nuclear envelope are lined with specialized proteins that allow the transport of substances into and out of the nulcleus
nuclear pores
the subunits of ribosomes are synthesized in the
nucleolus
the enzymes in one lysosome could not digest a cell because the _____ of the lysosome is lower than the neutral cytoplasm and therefore the lysosome enzymes would not be able to function fully in the cell cytoplasm
pH
what organelle protects all eukaryotic cells from toxic substances or toxic by-products of chemical reactions?
peroxisome
contractile vacuole in Paramecium
pump excess water out of the cell
lipids, detoxifying enzymes, and membrane components are produced and stored in the _____ endoplasmic reticulum
smooth
which of the following are correct concerning plant organelles called plastids?
some assemble and store starch, they contain their own DNA and ribosomes, and some, such as chloroplasts, synthesize pigments
select all of the characteristics of organelles
surrounded by membranes, studded with membrane proteins, and contain distinct proteins
select all of the following that are functions of the cytoskeleton in the cell
transportation, aids cell division, and structural support
plant cells have large central _____ where water, salts, and sugars are stored and where materials are broken down and recycled with enzymes similar to lysosomes in animal cells
vacuole
membranous spheres that transport materials inside the cell as part of the endomembrane system are called
vesicles
membrane proteins synthesized in the ER are transported in _____ to the _____, where the proteins will complete their folding and be packaged for export to the cell membrane
vesicles; Golgi apparatus