2.1 Cell Structures Flashcards
Organelle
An internal functional structure that’s located within the cytosol of a cell
Plasma membrane
A dynamic barrier that surrounds the cytosol of the cell
Nuclear envelope
A 2-layer membrane that enclose the nucleus of a eukaryotic cell
Endomembrane system
A group of interacting organelles btwn the nucleus and the plasma membrane
Endoplasmic Reticulum (ER)
A membrane-bound organelle that’s folded into flattened sacs/tubes, and is often an outgrowth of the nuclear envelope in a eukaryotic cell
Rough ER
Areas of ER with ribosomes attached to surface
Smooth ER
Areas of ER without attached ribosomes
Vesicle
A small, membrane-bound organelle that may transport, store, or digest substances within a cell
Vacuole
A liquid-filled organelle that stores waste and aids in cellular metabolism and water balance
Lysosome
A small, membrane-bound organelle that contains digestive enzymes, which aids in waste disposal
Golgi body
An organelle with folded membranes where the final packaging of proteins occurs
Mitochondrion
An organelle with 2 membranes: the site of most ATP synthesis during aerobic cellular respiration
Plastid
A membrane-bound organelle that’s involved in photosynthesis/storage in plants and algae
Chloroplast
A double-membrane-bound organelle that contains enzymes/pigments, which are used to perform photosynthesis in eukaryotic cells
Chromoplast
An organelle that makes and stores pigments other than chlorophyll
Amyloplast
An organelle that stores starch
Cytoskeleton
A dynamic system of filaments that provides cell structure, helps with cell division, and enables the cell and inner organelles to move around
Microfilament
A fibre structure that’s made from actin, which is part of the cytoskeleton and is located in the cell’s cytosol
Flagellum
A whiplike tail that’s used in propulsion of both prokaryotic and eukaryotic cells
Cilia
Tiny, hair-like structures that move water/mucus in eukaryotes: used for movement of prokaryotic cells
Cell wall
The outer barrier of a plant cell: the cell all surrounds the plasma membrane and gives structure to the plant
Primary wall
A cellulose coating that surrounds a plant cell
Secondary wall
A coating that’s added to a plant cell wall: it’s more rigid and often thicker than the primary cell wall
Extracellular matric (ECM)
A molecular system that supports/protects a cell: a cell’s environment
Cell junction
A structure that allows cells to interact with each other and the surrounding environment
Nucleus function
Protects/controls DNA access; makes ribosome subunits
ER function
Routes/modifies new polypeptide chains; synthesizes lipids; other functions
Golgi Body function
Modifies new polypeptide chains; sorts and ships proteins/lipids
Transport/secretory vesicle function
Transports substances within a cell and or releases them from the cell
Mitochondrion function
Generates ATP and other molecules
Chloroplast function
Produces sugars using light energy, CO2, and water
Lysosome function
Carries out intracellular digestion
Peroxisome function
Inactivates toxins
Vacuole function
Provides storage and contains waste; in plants, maintains cell size/shape
Ribosome
Assembles polypeptide chains that are used to form proteins
Centriole
Makes microtubules for the cytoskeleton; involved in cell division (mitosis - PMAT)
Organelles with a membrane
Nucleus, ER, Golgi body, Transport vesicle, Mitochondrion, Chloroplast, Lysosome, Peroxisome, Vacuole
Organelles WITHOUT a membrane
Ribosome, centrioles
Endomembrane system: Nucleus
DNA instructions for making proteins– transcribed into RNA, which moves–> nuclear pores –> in cytosol
Endomembrane system: Rough ER
Some of RNA in cytosol is translated into polypeptide chains by ribosomes on rough ER. Chains enter rough ER– modified into final form
Endomembrane system: Vesicles
Bud from rough ER, carry new proteins to Golgi bodies. (Other proteins migrate thru rough ER interior–> smooth ER)
Endomembrane system: smooth ER
Some proteins from rough ER packaged into vesicles and shipped to Golgi– other become enzymes–> assemble lipids or inactivate toxins
Endomembrane system: Golgi Body
Proteins arriving in vesicles from the ER are modified into final form and sorted. New vesicles carry them to the plasma membrane or lysosomes.
Endomembrane system: Plasma membrane
Golgi vesicles fuse with the plasma membrane. Lipids/proteins of a vesicle’s membrane fuse with the plasma membrane, and the vesicle’s contents are released to the exterior of the cell.
Difference between cytoplasm and cytosol
“Cytoplasm”: refers to all internal cell components. “Cytosol”: Is the liquid portion of the cell, but more precise
How many layers does the nuclear envelope have?
Two lipid bilayers folded together
Outer bilayer of membrane is continuous with ___ ____
Endoplasmic Reticulum
Nuclear envelope allows __ and ___ to cross freely
Water and gases
What do proteins that attach to the nuclear envelope’s inner surface do?
Anchor the DNA molecules and keep them organized. During mitosis, proteins pass DNA to daughter cells
Nucleoplasm
Viscous fluid similar to cytosol. Semifluid interior portion of nucleus
Nucleolus
Dense, irregularly shaped region where subunits of ribosomes are assembled from proteins and RNA
Nuclear envelope
Pore-riddled double membrane that controls which substances enter/leave nucleus
Chromatin
Total collection of all DNA molecules and associated proteins in nucleus
Nucleolus
Rounded mass of proteins and copies of genes for ribosomal RNA used to construct ribosomal subunits
Function of endomembrane system
Makes lipids, enzymes, and other proteins for secretion/insertion into cell membranes, destroying toxins, and recycling wastes
Common EM system components
Nucleus, rough ER, vesicles, smooth ER, Golgi body, plasma membrane
ER is an extension of ____ ____
nuclear envelope
Two kinds of ER
Smooth and rough
Rough ER function
Ribosomes synthesize polypeptide chains, released into ER interior. Inside– proteins fold and take complex structure
Smooth ER function
Doesn’t make proteins. Some proteins made in rough ER– enzymes in smooth. Enzymes produce cell membrane’s lipids
Vesicle functions
Transport proteins to other organelles
Peroxisome
Contains enzymes that digest fatty acids and amino acids
Plant and animal cells contain vesicles called ____
Vacuoles
Vacuole function
Isolate/dispose wastes, debris, and toxic materials, maintains cell fluid pressure
Large central ___ in plant cells
Vacuole
Lysosome function
Lysosomal enzymes empty in vacuoles and digest its content.
Vesicles fuse and empty their contents in a ____ _____
Golgi body
Golgi body function
Puts finishing touches on polypeptide chains/lipids that are delivered from ER. Attaches phosphates, sugars– sorted and packaged into new vesicles and delivered
All eukaryotic cells make ____ in mitochondria
ATP
ATP
Adenosine Triphosphate
Plants and some algae have special organelles, ____
Plastids
Mitochondrion has 2 membranes, one highly folded inside the other
Mitochondrial matrix, intermembrane space
Mitochondria resemble bacteria in ___ ___ ____
size, form, biochemistry
Mitochondria have their own ___ and ____ independently in cell
DNA, divide
Chromoplasts contain ___ and ___ carotenoids
orange and red
Orange and red carotenoids revealed in ____
fall
Amyloplast
Unpigmented plastids that store starch grains. Abundant in plant cells, stems, tubers, and seeds
Cytoskeleton is between ___ and ___ ____
Nucleus and plasma membrane
Parts of cytoskeleton ___, ___, and move ____ ___
reinforce, organize, and move cell structures, and often the whole cell
Some cytoskeleton structures ____
Permanent
Microtubules form ____ _____
Dynamic scaffolding
Intermediate filaments are the most ___ part of a cell’s cytoskeleton
Stable
Intermediate filaments
Strengthen and maintain cell/tissue structures, and are toughest of cytoskeleton filaments
Secondary plant cell wall develops in ____
later growth stages
Primary wall is ___ and ___
Thin and pliable
At maturity, plant tissues stop enlarging and secrete material onto inner surface of primary wall, this forms ____ ____
Secondary wall
ECM is a ___ and ____ is secreted by cells and varies with tissue type
Non-living, complex mixture of fibrous proteins
ECM ___ and ___ cells , ___ , ___ , ____
Supports and anchors cells, separates tissues, and functioning in cell signaling
Bone is mostly ____
ECM
ECM is basis of ____ ____
Tissue organization, and provides structural support
Cell junctions
Connect a cell to other cells and to the environment. Cells send/receive ions, molecules, and signals through junctions.
how are cells similar to organs?
they all have organelles which help them function
organelle
a structure within a
cell with a specific function
cell membrane (animal cells)
surrounds the cell and protects it.
Controls the movement of
substances into and out of the
cell.
cell wall (plants)
tough outer
layer that surrounds plant cells
cytosol
fluid inside cells
nucleus
controls the cell’s
activities, contains DNA
The DNA inside the nucleus
contains the instructions for
producing other materials
The Nucleus is surrounded by the
____________ (a membrane) and also contains the _________
nuclear envelope, nucleolus
nucleolus
makes ribosomes
nuclear envelope
consists of two lipid bilayers that are folded together
Outer layer continuous with
endoplasmic reticulum (er)
Membrane proteins are
embedded in a lipid bilayer
Allows water and gases to
transport freely, other
substances need help of system
transporter
ribosomes
build proteins, may be free floating or
attached to the Endoplasmic Reticulum.
Builds proteins by attaching AMINO ACIDS into chains.
Builds Enzymes (a type of protein) which are important
in breaking/building other molecules
endomembrane system
a group of interacting
organelles between the nucleus and the plasma membrane
Its main function is to make lipids, enzymes, and other
proteins for secretion and insertion into cell membranes
Can also destroy toxins and recycle wastes.
smooth endoplasmic reticulum
makes lipids, steroids, breaks
down toxins, releases calcium
rough endoplasmic reticulum
covered with ribosomes, stores
proteins for later transport
Substances made in the ER are
transported/stored with
_________ (small, membrane
bound containers)
vesicles
golgi body
an organelle that processes,
packages and transports materials produced in
the cell.
explain briefly how a substance enters the body and leaves through the endomembrane system
substances enter the golgi body in vesicles
golgi body processes materials produced from other parts of the cell
products leave in vesicles and may travel to other parts of the body
vacuoles (plants)
large
membrane bound structures
Acts as storage compartments
Keeps cell firm by pushing
against cell walls
Disposal site for harmful
chemicals
May contain defensive
chemicals
vacuoles (animals)
smaller transport sacs
lysosomes
organelles that
contain enzymes that digest other
molecules
lysosome functions
Fighting Diseases
Digestion
Recycling old cell parts
Killing the Cell
mitochondria
site of cellular respiration which produces energy
cristae
folds of inner membrane increase surface area = more reactions
matrix
fluid where reactions
occur
chloroplasts
photosynthetic organelles,
uses sunlight energy to
make sugars
ONLY FOUND IN PLANTS
Green colour comes from
Chlorophyll
Chlorophyll helps capture
sunlight energy
cytoskeleton
provides cell structure, helps with
cell division, allows organelles to move
microtubule
support tube made of tubulin proteins
-form scaffolding for support when needed
microfilament
structure made of actin proteins
Used in muscles for movement
Help strengthen cells
cilium
microtubules used for
movement/transporting substances
Paramecium move with the help of cilia
Mucus is moved via cilia in your lungs
flagellum
long tail-like microtubules used
for movement
Sperm cells
pseudopods
limb like structures formed by amoeba
Microtubules help cell change shape to move/engulf food
