Cell Structure and Function Test Review - AP Bio

nucleus

contains most of the genes (DNA) in a eukaryotic cell, has a nuclear envelope, nuclear membrane is a double membrane, pores regulate entry and exit of molecules from the nucleus, DNA and proteins form genetic material called chromatin

nucleolus

inside the nucleus, site of ribosomal RNA synthesis, becomes visible during cell division

mitochondria

site of cellular respiration, a metabolic process that generates ATP

chloroplasts

found in plants and algae, the site of photosynthesis, contains the green pigment chlorophyll

ribosomes

made from rRNA and protein, uses info from DNA to make proteins, proteins made in cytosol are free and stay in the cell, proteins made on outside of ER are bound and leave the cell

endoplasmic reticulum

accounts for more than half of the total membrane in eukaryotic cells, composed of rough and smooth regions, involved in protein and lipid synthesis, continuous with the nuclear envelope

rough ER

ribosomes stud the surface, distributes transport vesicles, abundant in cells that secrete proteins

smooth ER

lacks ribosomes, synthesis of lipids/phospholipids/steroids, detoxifies poison, stores calcium in muscle cells

golgi apparatus

consists of flattened membranous sacs called cisternae, modifies products of the ER, manufactures certain macromolecules, sorts and packages materials into transport vesicles

lysosomes

a membranous sac of hydrolytic enzymes that can digest macromolecules, uses enzymes to recycle cell’s own organelles

• Tay-Sachs, lack of lysosome enzymes lead to blindness/seizures/death

vacuoles

maintenance compartments, food vacuoles (formed by phagocytosis), contractile vacuoles (pumps excess water out of cells), central vacuoles (found in plant cells, holds organic compounds and water), plant cells have a larger vacuole and animal cells have many smaller vacuoles

cell membrane

acts as a protective, selectively permeable barrier that separates the interior of the cell from the outside environment while controlling the movement of substances in and out

cell wall

an extracellular structure of plant cells, not in animal cells, wall protects the plant cell, maintains the shape, and prevent an uptake of water

cytoplasm

holds and surrounds internal structures and organelles

cytoskeleton

a network of fibers extending throughout the cytoplasm, provides mechanical support, maintains cell shape, anchorage for many organelles, interacts with motor proteins to produce motility, changes shape of the cell, composed of microtubules, microfilaments, intermediate filaments

microtubules

hollow tubes made of tubulin that provide structural support and are involved in cell division and intracellular transport.

microfilaments

thin, thread-like fibers made of actin that support cell shape, enable cell movement, and are involved in muscle contraction and cytokinesis.

intermediate filaments

protein filaments that provide mechanical strength, helping to maintain cell shape and resist tensile forces. They are a component of the cytoskeleton, supporting the structure of cells.

prokaryotic cells have…

no nucleus, DNA in an unbound region, no membrane bound organelles, cytoplasm bound by plasma membrane, cell walls contain cellulose/chitin

eukaryotic cells have…

DNA in nucleus that is bound by a membranous nuclear envelope, membrane bound organelles, cytoplasm in the region between the plasma membrane and the nucleus, generally larger than prokaryotic cells

animal cells have…

flexible cell membrane, round/irregular shape, multiple small vacuoles, contains centrioles for cell division and lysosomes for waste breakdown

plant cells have…

tough outer cell wall made by cellulose, contains chloroplasts and chlorophyll, fixed rectangular shape, has one large vacuole, no lysosomes or centrioles

all cells have in common…

plasma/cell membrane, semifluid substance (cytosol/cytoplasm), chromosomes (carry genes), ribosomes (make proteins)

what are the three domains

bacteria, archaea, eukarya

what type of cell is in the bacteria domain

prokaryotic cells (w/ peptidoglycan and ether linkages)

what type of cell is in the archaea domain

prokaryotic cells (w/o peptidoglycan and ether linkages)

what type of cell is in the eukarya domain

eukaryotic cells

what is the main factor that limits cell size?

surface area-to-volume ratio which affects the efficiency of nutrient absorption and waste removal

what is the disorder related to organelles

Tay-Sachs, lack of lysosomes which lead to less lipids breakdown which causes blindness, seizures, death

where can DNA be found besides the nucleus

chloroplasts (plants) and the mitochondria (animals)

what are the parts of the endomembrane system

nuclear envelope, endoplasmic reticulum, Golgi apparatus, lysosomes, and vacuoles

what does the endosymbiotic theory suggest

that eukaryotic cells evolved from symbiotic relationships between prokaryotic organisms, particularly regarding mitochondria and chloroplasts, reintroduced by Lynn Margulis 1963

microtubules

maintain cell shape, guide movement of organelles, separate chromosomes during cell division, movement

cilia/flagella

extend from surface, made of microtubules arranged in a 9 +2 pattern (nine doubles in a ring around a part in the center), cilia is short and larger in number while flagella is longer and shorter in number

microfilaments

bear tension, resist pulling forces within the cell, role in muscle contraction, cleavage furrow in cell division, amoeboid movement, a circular flow of cytoplasm within cells

microfilaments

thin, thread-like structures made of actin filaments that play key roles in maintaining cell shape and enabling cellular movements

intermediate filaments

support cell shape and anchor organelles in place, more permanent than the other two classes