Chapter 4 Flashcards
the most important factor that limits the size of a cell is the?
the surface-area-to-volume ratio of the cell
where are the prokaryotes DNAs located?
nucleoid
Prokaryote cells components
cytoplasm, ribosomes, nucleoid, plasma membrane, cell wall, capsule, pili, and flagellum.
How do prokaryotes move?
by rotating their flagella
What is the bacterial cell wall made of?
peptidoglycan
How does penicillin affect bacteria?
interfere with the ability of bacteria to cross-link peptides in their cell wall
How is compartmentalization achieved in eukaryotes?
endomembrane system
all eukaryotic cells are supported by an internal protein…
cytoskeleton
The surface of the nucleus is bounded by two phospholipids bilayer membranes, which together make up the…
nuclear envelope
The animal cell is composed of
nucleus, cytoskeleton, centriole, cytoplasm, lysosome, ribosomes, RER, SER, Golgi apparatus, mitochondrion, peroxisome, and plasma membrane
The plant cell is composed of
RER, SER, ribosome, Golgi apparatus, chloroplast, adjacent cell wall, cell wall, plasma membrane, plasmodesmata, cytoplasm, mitochondrion, cytoskeleton, and nucleus
What is chromatin?
DNA linear chromosomes
The largest of the internal membrane is called?
Endoplasmatic Reticulum ER
What is synthesized in the RER?
Proteins
What is synthesized in the SER?
Lipids and steroids
The function of Golgi is?
collection and distribution of molecules
Golgi’s front is called…
receiving and or cis near to the ER
Golgi’s back or…
trans face
Lysosomes
contain digestive enzymes active at acid pH
3 types of fibers compose the cytoskeleton
actin filaments, microtubules, and intermediate filaments
centrosomes are…
microtubule-organizing centers
adhesive junctions
found in all animals. they mechanically attach the cytoskeleton of one cell to the cytoskeleton of another cell. muscle and skin epithelium
adherens junctions
based on cadherin. ca2+ dependent, flexible connections between cells
Desmosomes
cadherin-based junction. Only vertebrates. Desmosomes join adjacent cells. support tissues against mechanical stress
Hemidesmosomes
connect cells to the basal lamina. integrins
Tight junctions
Only vertebrates. Claudins. forms between cells and acts as a wall within the tissue
communicating junctions: gap junctions
in invertebrates they are formed by pannexins. invertebrates they are formed by connexons. provide passage to small substances. they can open and close
Plasmodesmata
plants.plasma membranes of adjacent cells can come into contact with one another
