Chapter 6 - The Cell Flashcards
Centro
= the center
Soma
= a body
Chloro
= green
Cyto
= cell
Cili
= hair
ell
= small
Endo
= inner
Eu
= true
Extra
= outside
Flagell
= whip
Glyco
= Sweet
Lamin
= sheet/layer h
Lyso
= loosen
Micro
= Small
Tubul
= a little pipe
Oid
= like
Phago
= eat
Desma
= a band or bond
Pro
= before
Karyo
= Nucleus
Pseudo
= false
pod
= foot
Thylaco
= sac or pouch
Trans
= across
Actin
A globular protein that links into chains, two of which twist helically about each other, forming microfilaments in muscle and other contractile elements in cells.
Cell Wall
A protective layer external to the plasma membrane in plant cells, bacteria, fungi, and some protists. In plant cells, the wall is formed of cellulose fibers embedded in a polysaccharide-protein matrix.
Central Vacuole
A membranous sac in a mature plant cell with diverse roles in reproduction, growth, and development.
Chloroplast
An organelle found only in plants and photosynthetic protists that absorbs sunlight and uses it to drive the synthesis of organic compounds from carbon dioxide and water.
Chromosome
A threadlike, gene-carrying structure found in the nucleus. Each chromosome consists of one very long DNA molecule and associated proteins.
Collagen
A glycoprotein in the extracellular matrix of animal cells that forms strong fibers, found extensively in connective tissue and bone.
Crista(plural, cristae)
An infolding of the inner membrane of a mitochondrion that houses the electron transport chain and the enzyme catalyzing the synthesis of ATP.
Cytoplasm
The entire contents of the cell, exclusive of the nucleus, and bounded by the plasma membrane.
Cytoplasmic Streaming
A circular flow of cytoplasm, involving myosin and actin filaments, that speeds the distribution of materials within cells.
Cytoskeleton
A network of microtubules, microfilaments, and intermediate filaments that branch throughout the cytoplasm and serve a variety of mechanical and transport functions.
Cytosol
The semifluid portion of the cytoplasm.
Desmosome
A type of intercellular junction made of intermediate filaments in animal cells that functions as an anchor.
Endomembrane System
The collection of membranes inside and around a eukaryotic cell, related either through direct physical contact or by the transfer of membranous vesicles.
Eukaryotic Cell
A type of cell with a membrane-enclosed nucleus and membrane-enclosed organelles, present in protists, plants, fungi, and animals.
A eukaryote.
Extracellular matric(ECM)
The substance in which animal tissue cells are embedded, consisting of protein and polysaccharides.
Flagellum(plural, flagella)
A long cellular appendage made of microtubules specialized for locomotion.
Food Vacuole
A membranous sac formed by phagocytosis.
Gap Junction
A type of intercellular junction in animal cells that allows the passage of material or current between cells.
Glycoprotein
A protein covalently attached to a carbohydrate.
Golgi Apparatus
An organelle in eukaryotic cells consisting of stacks of flat membranous sacs that modify, store, and route products of the endoplasmic reticulus.
Granum(plural, grana)
A stacked portion of the thylakoid membrane in the chloroplast.
Function in the light reactions of photosynthesis.
Intermediate Filament
A component of the cytoskeleton made of subunits of keratin that includes all filaments intermediate in size between microtubules and microfilaments.
Lysosome
A membrane-enclosed sac of hydrolytic enzymes found in the cytoplasm of eukaryotic cells.
Microfilament
A solid rod of actin protein in the cytoplasm of almost all eukaryotic cells, making up part of the cytoskeleton and acting alone or with myosin to cause cell contraction.
Microtubule
A hollow rod of tubulin protein in the cytoplasm of all eukaryotic cells and in cilia, flagella, and the cytoskeleton.
Mitochondrial Matrix
The compartment of the mitochondrion enclosed by the inner membrane and containing enzymes and substrates from the citric acid cycle.
Mitochondrion(plural, mitochondria)
An organelle in eukaryotic cells that serves as the site of cellular respiration.
Nuclear Envelope
The membrane in eukaryotes that encloses the nucleus, separating it from the cytoplasm.
nuclear lamina
A netlike array of protein filaments that maintains the shape of the nucleus.
Nucleoid
A dense region of DNA in a prokaryotic cell.
Nucleolus(plural, nucleoli)
A specialized structure in the nucleus, formed from various chromosomes and active in the synthesis of ribosomes.
Nucleus
The chromosome-containing organelle of a eukaryotic cell.
Organelle
One of several formed bodies with specialized functions, suspended in the cytoplasm of eukaryotic cells.
Phagocytosis
A type of endocytosis involving large, particulate substance, accomplished mainly by macrophages, neutrophils, and dendritic cells.
Plasma Membrane
The membrane at the boundary of every cell that acts as a selective barrier, thereby regulating the cells chemical composition.
Plasmodesma(plural, plasmodesmata)
An open channel in the cell wall of a plant through which strands of cytosol connect from an adjacent cell.
Plastid
One of a family of closely related plant organelles that includes chloroplasts, chromoplsts, and amyloasts.
Prokaryotic Cell
A type of cell lacking a membrane-enclosed nucleus and membrane-enclosed organelles.
Found only in domains Bacteria and Archaea.
Pseudopodium(plural, pseudopodia)
A cellular extension of amoeboid cells used in moving and feeding.
Ribosome
A cell organelle constructed in the nucleolus and functioning as the site of protein synthesis in the cytoplasm.
Consisting of rRNA and protein molecules, which make up two subunits.
Rough ER
That portion of the endoplasmic reticulum studded with ribosomes.
Smooth ER
That portion of the endoplasmic reticulum that is free of ribosomes.
Stroma
The fluid of the chloroplast surrounding the thylakoid membrane.
Involved in the synthesis of organic molecules from CO2 and H2O.
Thylakoid
A flattened membrane sac inside the chloroplst, used to convert light energy to chemical energy.
Tight Junction
A type of intercellular junction in animal cells that prevents the leakage of material between cells.
Tonoplast
A membrane that encloses the central vacuole in a plant cell, separating the cytosol from the vacuolar contents.
Transport Vesicle
A tiny membranous sac in a cells cytoplasm carrying molecules produced by the cell.
Vacuole
A membrane bound vesicle whose specialized function varies in different kinds of cells.
Vesicle
A sac made of membrane inside of cells.
2 Major types of cells
Prokaryotic(bacteria/archae domains)
- smallers, simplier - lack membrane bound nucleus and organelles(still have DNA in nucleoid region)
Eukaryotic(animal, plant, fungi, protist kingdoms)
- larger and more complex - many specialized membrane bound organelles and nucleus
All cells types have:
- plasma membrane
- DNA
- Ribosomes
- Cytoplasm
Only in Animal Cells:
- Lysosomes
- Centrosomes with centrioles
- Flagella(except some plant sperm)
- Gap junctions, tight junctions, desmosomes
Only in Plant Cells:
- cell wall(not in animal)
- plasmodesmata in cell wall
- central vacuole
- chloroplasts
- Amyloplasts
- Chromoplasts
- Plasma Membrane
Function - selective barrier that controls what can enter and leave cell, contains cytoplasm, defines cell as separate from environment.
Structure - double layer of phospholipids w/ proteins embedded in them; carbohydrate side chains on outside.
- Nucleus
Function - Contains genes(DNA)
Structure - enclosed by double layer nuclear membrane
- membrane has pores - protein structure called pore complex lines pore, controls what can enter or leave nucleus.
- Nuclear lamina - lines inside of nuclear membrane, has protein filaments(intermediate filaments), maintains shape of nucleus.
- Nucleolus
Function - area w/in nucleus where ribosomal components synthesized
Structure - dense area w/in nucleus near chromatin
- Ribosomes
Function - Site of protein synthesis
Structure - Made of ribosomal RNA(rRNA) and protein; 2 subunits.
A - free ribosomes: in cytosol, proteins they make are used in cytoplasm
B - bound ribosomes: attached to endoplasmic reticulm; makes proteins exported out of cell or used w/in other cell organelles.
Endomembrane System
Various membrane structures that are responsible for protein and lipid synthesis and detoxification of poisons; may be directly connected or use vesicles to move cellular products between members.
Members - nuclear envelope, ER, Golgi apparatus, lysosomes, vacuoles/vesicles, plasma membrane.
- Endoplasmic Reticulum(ER)
Overall Structure - Network of membranes arranged in sacs(cisternae); has internal compartments(ER lumen) that is separate from cytosol.
2 regions- Smooth and Rough ER
5a. Smooth ER
Function - synthesis of lipids, metabolism of carbohydrates, detoxification of drugs; makes sex hormones.
Structure - No ribosomes give “smooth” appearanece.
5b. Rough ER
Function - Secretion of specialized proteins Rough ER packages proteins into transitional ER then into bubbles called transport vesicles which move to Golgi Apparatus.
Structure - Contains ribosomes giving “rough” appearance.
- Golgi Apparatus
Function - Accepts transport vesicles containing cellular products from ER; clearing house–modifies, sorts, ships proteins readys to be secreted or for use somewhere else in cell; places ID tags on outside of vesicles leaving Golgi to arrive at correct location
Structure - Flat membranous sacs(cisternae)
-2 opposite sides: Cis face(receiving); Trans face(shipping)
- Lysosome
Function - Contains enzymes which digest macromolecules
- Enzymes work in a pH of 5(different from cells) - Autophagy: recycling of cells own organic materials - Phagocytosis: digestion of large food particles; food vacuoles merge w/ lysosomes for digestion
Structure - membrane bound sacs of digestive enzymes
- Vacuoles(larger) and Vesicles
Structure - large membrane bound sacs
3 types:
- Food Vacuoles: function - formed by phagocytosis; allow digestion of large food particles - Contractile: Function - freshwater protist use to pump out excess internal water - Central: Function - in plant cells, enclosed by tonoplast membrane; storage, disposal of waste;pigments;poisons;growth;holds water
- Mitochondria
Function - site of cell respiration(process of extracting energy from food)
Structure - enclosed by two membranes
- outer membrane smooth; inner convoluted(cristae: increases surface area) - intermembrane space: b/t inner and outer membranes - mitochondrial matrix: w/in inner membrane - mitochondria have own DNA, ribosomes; can reproduce itself
- Chloroplasts
Function - site of photosynthesis in plants and algae
Structure - has 2 membranes
- contains chlorophyll, a green pigment in thylakoids(sacs of membranes) - Grana: sacks of thylakoids - Stroma: Fluid outside thylakoids - contains own DNA and ribosomes
- Other Plastids
Function - storage of various cellular materials
- Amyloplasts: colorless; stores starch - Chromoplasts: stores plant pigments that give flowers and fruits colors
Structure - double membrane organelle
- Cytoskeleton
Function - overall: network of fibers in cytoplasm; organizes and anchors organelles, gives structural support.
3 types(microtubules, microfilaments, intermediate filaments)
12a. Microtubules(types of cytoskeleton)
Function - compression resistant for maintaining shape of cell
- provides organelle "tracks" - moves chromosomes during cell division - cell motility: Cilia and Flagella: locomotive appendages
Structure - thickest of 3 types, hollow, made of tubulin
- can be disassembled and re-built from pieces
12b. Microfilaments(types of cytoskeleton)
Function - bears tension(pulling forces), supports cell shape
Muscle contraction - microfilamanets of actin interact w/ another protein(myosin)
Cleavage furrow - tightening band of microfilaments divides cells
Gel-sol State:
- cytoplasm on periphery of cell thicker(gel)l inner area is more fluid(sol) - Pseudopodia: cellular extensions of amoebas caused by localized breakdown of microfilaments from gel to sol state. - Cytoplasmic streaming: flow of cytoplasm: sol to gel state; distributes substances w/in cell
Structure - solid, made of actin, twisted, double chain
Can be assembled and re-built from pieces.
12c. Intermediate Filaments(types of cytoskeleton)
Function - provide shape and support of cell
Organelle location(nucleus anchor)
Makes up nuclear lamina(inside lining of nucleus)
forms desmosomes, rivets that hold cells together
Structure - larger than microfilaments, smaller than microtubles.
- made of keratin - PERMANENT
- Cell Surfaces and Junctions
Plant Cell Walls:
- function - shape, support, protectio - structure - fibrils of cellulose(polysaccharide) embedded in polysaccharide matrix, proteins.
EXM(extracellular matrix) of an animal cell
- function - support, adhesion, regulation to cells - structure - outside of plasma membrane
made mostly of glycoproteins(collagen)
bonded to integrins, proteins built into plasma membrane; allows communication b/t ECM and inside of cell
series of proteoglycan complex of polysaccharide molecules joined to protein cores
13a. Intercullar Junctions(cell surfaces/junctions)
Plants: Plasmodesmata - channels in cell walls; connects cells; allows exchanges of cytoplasm and cellular material b/t adjacent cells
Animals:
- Tight junctions - fused continuous connection bonding cells together, sealed; prevents leakage between cells - Desmosomes - rivets that anchor cells together; made of intermediate filaments - gap junctions(communicating) - communication; channels that connect cells; allows exchange of cytoplasm and cellular material b/t adjacent cells.
Endomembrane System Purpose
a collection of organelles that possess membranes
that may or may not be in continuous contact. Their similar membrane structures
allows them to move cellular material from one area to another as processing
occurs.
Endomembrane System members
nuclear membrane, endoplasmic reticulum,
Golgi apparatus, lysosomes, vacuoules and the plasma membrane.
Advantages of Compartmentalization in Eukaryotic Cells
cell processes need particular environmental conditions to operate properly so keeping these processes separate from the rest of the cell is necessary.
