The Cell Flashcards
To help memorize the content easier and faster
cell membrane
controls what goes in and out of the cell, made of phospholipids
mitochondria
- powerhouse of the cell
- produces ATP energy by using glucose and oxygen
- the inner surface is called cristae and it contains enzymes that are responsible for cellular respiration and this is where energy is produced
- inner fluid-filled space is called the matrix and it has its own DNA molecules and ribosomes that resemble those of prokaryotic cells
- self-replicating
vacuole
- (plant) large membrane-bound container that stores water, nutrients, and waste
- provides structure
- an extension of the ER membrane
nucleus
controls all cellular activities, including reproduction & contains DNA
nucleolus
dark spots in nucleus that are the sites of ribosome production
chromatin
- a mass of threads that condense chromosomes during cell division
- contain DNA, RNA, and proteins
chromosomes
rod-like structures that efficiently packages the cell’s DNA before cell division and control of gene expression
nuclear envelope
double membrane that controls what goes in and out of the nucleus and is a continuation of the membranes of the ER
centrioles
- function in organizing microtubules in cell division & forms basal bodies
- located near the nucleus
- short cylinders with 9+0 pattern of micro-tubular triplets
- 1 pair of centrioles lying at right angles to each other next to the nucleus
Lysosomes
- digests food
- formed by the Golgi apparaus
- destoys invading bacteria
- auto digestion of damaged cell components of mitochondria
- breakdown of a whole cell
ribosome
- site of protein synthesis and is made of rRNA and protein
- transports proteins to the Golgi
smooth endoplasmic reticulum (ER)
produces fat & detoxifies drugs and chemicals
rough endoplasmic reticulum (ER)
- protein synthesis occurs here
- send raw proteins to where they are needed in cell
Golgi apparatus
- stacks of flattened, hollow cavities enclosed by membranes
- processes, packages, secretes proteins
- located near to the nucleus and ER
- each sac contains enzymes that modify proteins as they pass through
vesicles
- small vacuoles that store nutrients
- formed by pinching off from the Golgi apparatus, or endocytosis of the cell membrane, or extension of the ER membrane
cell wall
(plant) protective barrier outside the cell membrane of plant cells
What are the three principles of the cell theory?
- all living things are made of cells
- the cell is the basic unit of life
- all cells come from the division of pre-existing cells
What is the endosymbiont theory?
Cells started out as prokaryotic cells. At some point, a large prokaryote ingested a bacteria that could produce ATP. For some reason, it did not digest the bacteria. Over time, that bacteria became what we now know a the chloroplast
What must a living organism be able to do?
- metabolize
- grow
- reproduce
- respond to stimuli
- consume food source
- maintain homeostasis(be able to not change significantly)
nuclear pores
pores in the nucleus that allow selected molecules into and out of the nucleus & allows RNA pass into the cytoplasm
Describe the ER
- a system of membranes that form canals to transport substances
- provides an increase in surface area where chemical reactions can occur
- provides storage space for products synthesized by the cell
polysomes
free-floating ribosomes within the cytoplasm and consists of clusters of ribosomes bunched together that produce proteins that will be used inside the cell
Describe the fluid mosaic model
- the liquid portion is composed of side by side phospholipids arranged in a bilayer(hydrophllic head + hydrophobic tail)
- solid layer consists of a variety of proteins that are suspended or anchored at various points on its surface
- forms a fluid sea in which the membrane is selectively permeable
peroxisomes
- single membrane organelles
- remove hydrogen atoms from small molecules and join the hydrogen atoms to oxygen to form hydrogen peroxide and then break it down into water and oxygen
chloroplast
- (plant cells) contain pigments that give plant cells their colours
- double membrane organelle in which photosynthesis occurs
- fluid-filled space is called stroma that contains stacked up structures called grana that contain flattened sacs called thylakoids
- stroma contains DNA, ribosomes, and enzymes that synthesize carbohydrates from CO2 and H2O
chlorophyll
- located within the thylakoid membranes of grana
- captures solar energy that is needed to produce carbohydrates
cytoskeleton
-network of filamentous protein structure that helps maintain shape, anchor organelles, and help the organelles move as necessary
-primary constituents aremicrotubules and
microfilaments
-cytoplasm is the fluid interior
microtubules
hollow, cylindrical aggregates of tube-like structures that help give the cell shape and also involved in other cell processes
- made up of 13 rows of globular proteins arranged to form a hollow tube
- serve in moving materials within the cell, cell movement, cytoskeleton structure
Basal bodies
- direct formation of cilia and flagella
- short structures with a 9+0 arrangement that assist in the formation of the spindle apparatus in cell division
microfilaments
long, thin contractile rods that appear to be responsible for the movement of cells
- made up of double filaments arranged in helical pattern with each filament consisting of numerous globular proteins joined together
- serve in anchoring organells, moving organelles within the cell, cell movement, and form a part of the cytoskeleton
Cilia
- short hair-like projections that function in cell membrane (paramecium,cells of human respiratory tract)
- consist of a membrane-bound cylinder with 9 doublet +2 arrangement of microtubules
- doublets slide along one another to create movement
- shorter than flagella and beat stiffly like oars in one direction
Flagella
- membrane bound cylinder with 9+2 arrangement of microtubules (same as cilia)
- beat in undulating whip-like fashion
- function in cell movement (eg sperm cells)
Extracellular matrix
In plant cells: -maintain shape -prevent water excessive uptake -resist gravity In animal cells: -maintain support -assist in adhesion -facilitate movement -form cell-to-cell communication -potentially assist in differentiation
secretory
- package enzymes and hormones into vesicles
- go to the cell membrane and expel chemical into blood or tissue space.
Compare animal and plant cells
plant cells: -chloroplast -central vacuole -cell wall + cell membrane -stores starch animal cells: -centrioles -cilia and flagella -cell membrane only -stores glycogen
What is an organelle?
Small bodies that have specific functions.
Compare prokaryotic and eukaryotic cells
prokaryotic: -lack true nucleus -lack most organelles -cell wall eukaryotic: -cell wall + cell membrane -nucleus present -membrane bound organelles
Why would a cell want to divide?And how?
- to increase surface area to volume ratio so enough SA to maintain amount of material that need to enter and exit
- dividing, changing shape, or infolding or outfolding
