the cytoplasm and cellular organelles Flashcards
t/f ? all living cells in unicellular organisms contain internal cytoplsmic compartment and a nucleus
false! in a MULTICELLULAR
cytosol
- jelly like substance in cells
- provides fluid necessary for biochemical reactions
organelle
one several different types of membrane-enclosed bodies in the cell. all with a unique function!
cytoplasm
oorganelles and cytosol
nucleus
cells central organelle
- cells DNA
endoplasmic reticulum
- system of channels that is continuous with nuclear membrane
- covers the nucleus and composed of same lipid bilayer material
- provides passages throughout much of cell to help in transporting, synthesizing and storing materials
- two types: rough and smooth
Rough ER
- ## dotted with embedded granules (ribosomes)
ribosome
- organelle that serves as the site of protein synthesis
- 2 rRNA subunits that wrap around mRNA to start process of translation and protein synthesis
Smooth ER
- synthesis of lipids
- synthesizes phospholipids and steroid hormones
- metabolizes some carbs and performs detoxification (breaks down certain toxins)
golgi apparatus function
- responsible for sorting, modifying and shipping off the products that come from the rough ER
- post office
- one side receives vesicles, sorts through aparatus, released from opposite side after being repackaged into new vesicles
lysosomes
- an organelle that contains enzymes that break down and digest unneeded cellular components (like damaged organelles)
- breaks down foreign material
- janitor
autophagy
- self eating
- process of cell digesting its own structures
autolysis
- process of controled cell death
- lysosomes triggered to open up and released their digestive enzumes into cytoplasm to kill the cell
mitochondria function
- energy transfomer of cell
- cellular respiration occurs
- converts energy stored in nutrient molecules into ATP and provides usable energy for the cell
- reason why you need to constantly O2
what type of cells have lots of mitochondria?
muscle cells! and nerve cells!
peroxisome
- contains mostly enzymes
- lipid metabolism and chemical detoxification
- serve to transfer hydrogen atoms from molecules to oxygen
- produce hydrogen peroxide to neutralize poisons
- oversee reactions that neutralize free radicals
- neutralize harmful toxins so they don’t wreak havoc in cells
- lots of peroxisomes in livers
Reactive oxygen species
the highly reactive products like peroxides and free radicals (reactive bc they hav free unpaired electrons, play role in destructive processes in body, cause cellular damage and cell death)
- used for cell functions like cell signaling processes and immune responses
Oxidative stress
used to describe damage to cellular components caused by ROS
- ROS can cause chain reaction where they make other molecules oxidized and reactive and they do the same to others
- ROS can also cause permenant damage to cellular lipids, proteins, carbs and nucleic acids (which can cause cancer)
- major contributor to aging process
mutation
- change in nucleotide sequence in a gene within a cells DNA
- potentially alters protein coded by that gene
Cytoskeleton
group of fibrous proteins that provide structural support for cells
- critical for cell mobility, cell reproduction and transportation of substances within the cell
- 3 different differents types of protein-based filaments: microfilaments, intermediate filaments and microtubules
microtubules
- structural filament made of subunits of protein called tubules
- maintain cell shape and structure
- resist compression of the cell
- play a role in positioning organelles within the cell
- make up two types of appendages important for motion: cilia and flagella
- one type: centrioles
what are centrioles? function?
cellular orgin point for microtubules extending outward during seperation of DNA during cell division. microtubules grow out from the centrioles by adding more tubulin subuints
microfilament
- thinner type of cytoskelatal filament
- made of twisted actin fibers (responsible for muscle contraction)
- actin filaments are long chains of single subunits and are pulled by thick filaments of myosin protein to contract the cell
- also creates a cleavage furrow to split cell in half during cell division
intermediate filament
- intermediate in thickness between microtubules and microfilaments
- they’re important for maintaining cell shape and structure
- resist tension
- help anchor organelle together within a cell and and link cells to cells by forming special junctions
