AP Biology Cell Quiz

cell/plasma membrane

a selective barrier that allows passage of oxygen, nutrients, and waste, generally made up of a double layer of phospholipids

nucleus

contains most of the DNA (has a nuclear envelope, membrane, pores, lamina, nucleolus)

ribosomes

carry out protein synthesis in two locations (in the cytosol or on the outside of the ER or the nuclear envelope)

rough endoplasmic reticulum

surface is studded with ribosomes, secrete glycoproteins, distributes transport vesicles (proteins surrounded)

smooth endoplasmic reticulum

lacks ribosomes, synthesizes lipids, metabolizes carbohydrates, detoxifies drugs & proteins

golgi apparatus

contains cisternae (flattened membranous sacs), modifies products of the ER, manufactures certain macromolecules, sorts & packages materials into transport vesicles

lysosome

membranous sac of hydrolytic enzymes that can digest macromolecules, work best in acidic environments

autophagy

a process of using enzymes to recycle the cell's own organelles & macromolecules

vacuoles

membrane-bound sacs, store water & other macromolecules, release waste

chloroplast

found in plant cells, have a double outer membrane, capture energy from the sun & produce sugar

mitochondria

capture energy from macromolecules, electron transport & ATP synthesis

cytoskeleton

network of fibers that organize cell structure & activity, supports the cell & maintains its shape

cell wall

extracellular structure with multiple layers, protects the plant cell, maintains shape, prevents excessive uptake of water

four things that all cells have in common

plasma membrane, semifluid substance called cytosol, chromosomes (carry genes), ribosomes (make proteins)

why do cells need to be small

to maintain a large surface area to volume ratio, allowing faster rates of chemical exchange between cell & environment

endosymbiotic theory

explains that eukaryotic cells may have evolved from prokaryotic cells

comparing plant & animal cells

plants have cell walls, chloroplasts, large central vacuoles, plasmodesmata

comparing prokaryotes & eukaryotes

eukaryotes have membrane-bound organelles, a nucleus, & are much larger, prokaryotes have their DNA in the nucleotide, eukaryotes have their DNA in the nucleus

plasmodesmata

channels that perforate plant cell walls

tight junctions

prevents fluid leakage

gap junctions

communication

desmosomes

strong welds to prevent ripping

pathway of a protein being secreted

nucleus → rough ER → vesicle → golgi → secretory vesicle → cell membrane → outside