bio 1110 components of a cell & their functions

prokaryotic cell

cells with no nucleus or cell compartmentalization

eukaryotic cell

cell with a nucleus

exhibits comparmentalization: many organelles that separate the interior of the cell

eukaryotic cells

genome

genetic content of an organism, including all its genes.

proteome

complete set of proteins that cell or organism can make

cytosol

central region for many metabolic activities of eukaryotic cells

catabolism

metabolic pathway that involves the breakdown of a molecule to generate output of energy

anabolism

synthesis of molecules and macromolecules; requires input of energy

enzyme

a protein that accelerates the rate of chemical reaction

metabolism

sum of chemical reactions which cells produce materials and utilize energy to sustain life

metabolic pathway

each step is catalyzed by a specific enzyme

ribosomes

where translation of mRNA occcurs; some in cytosol, attached to outer membrane of nuclear envelope or ER membrane, or even mitochondria or chloroplastse

endomembrane system

nuclear envelope, endoplasmic reticulum, golgi apparatus, lysosomes, vacuoles, vesicles, and cell (plasma) membrane

microtubules

hollow tubule composed of the protein “tubulin”

dynamic instability

single microtubules can oscillate between growing and shortening phases on each end

intermediate filaments

a twisted filament, can be composed of the protein “actin”

motor proteins

a category of cellular proteins that use ATP as energy to promote various types of movements

motor protein head

site where ATP binds and is hydrolyzed to ATP and inorganic phosphate

motor protein hinge

site binds in response to ADP binding and hydrolyses; bending causes movement!

motor protein tail

elongated area attached to other proteins or cellular molecules

hinge and tail create a structure called “lever arm”

nucleus

organelle found in eukaryotic cells that contains most of the cell’s genetic material

endomembrane system

membranes that enclose nucleus are a network of membranes called

what does the endomembrane system consist of?

nuclear envelope, endoplasmic reticulum, gogi apparatus, lysosomes, vacuoles, cell (plasma) membrane, and peroxisomes

nuclear envelope

double membrane consisting of an inner and outer membrane

vesicle

membrane-enclosed sac with a sperical shape

nuclear matrix

chromosomes and network of proteinsc

chromatin

nucleus composed of protein and DNA

nucleolus

droplet-shaped organelle where assembly of ribosomes occur

endoplasmic reticulum

network of membranes that form flattened, fluid-filled tubules (cisternae)

functions of the rough ER

studded with ribosomes

sorts protein (both synthesis and sorting)

inserts membrane proteins first through the rough ER to synthesize proteins

glycolysationgl

glycolysation

attachment of carbs to proteins and lipids

characteristics and functions of the smooth ER

no ribosomes

helps metabolize by detoxifying harmful organic molecules

contains calcium pumps that transport calcium to the ER lumen

primary site for synthesis of phospholipids which is the main contributor to the structure of cell membranes

metabolization within the smooth ER

enymes convert hydrophobic molecules to hydrophilic

more smooth ER’s means a higher breakdown rate, which contributes to tolerance of drugs

golgi apparatus

completes proteinf olding

further modifies products of the ER

sorts and packages materials into transport vesicle

lysosomes

found in animal cells

break down molecules and macromolecules

contains acid hydrolases, which are hydrolytic enzymes that use water to break chemical bonds (works best at low pH)

originates in the rough ER, then golgi directs them by recognizing the attached sugar, then packages them into the vesicles that become lysosomes

vacuoles

prominent organelles in plant cells, fungal cells, and certain protistsa

acid hydrolases

an enzyme that utilizes water to break down molecules at acidic pH

central vacuole

a large, fluid-filled organelle in plant cells that can occupy up to 90% of the cell's volume to maintain rigidity, store nutrients, and manage wast

contractile vacuole

remove excess water and maintain balance inside single-celled organisms within protists

peroxisomes

catalyze chemical reactions

found in liver cells of mammals

contains enzymes that remove hydrogen atoms from various substrates, transfers them to oxygen to produce hydrogen peroxide (H2O2)

if peroxisome recognizes hydrogen peroxide has become toxic, it also contains an enzyme that will breake the H2O2 down, producing H2O and hydrogen gas

catalyze

speed up chemical reactions

mitochondria

extracts energy from food to make ATP

folds in mitochondrial membrane are called cristae

cristae

folds in inner mitochondrial membrane

chloroplasts

why photosynthesis occurs

converts sunlight energy into chemical energy (sugars)

thylakoids

stacks of internal membranes