Cell Parts: Part I

Cell Theory

The cell is the basic unit of life; all cells come from preexisting cells.

Prokaryotic Cells

Cells lacking a nucleus or membrane-bound organelles.

Eukaryotic Cells

Larger, more evolved cells with a nucleus and membrane-bound organelles.

Cell Size Limit

Constrained by surface area-to-volume ratio and diffusion time to the center.

Nucleolus

A dark-staining nuclear structure containing DNA that codes for ribosomal RNA.

Smooth Endoplasmic Reticulum

An ER network continuous with the rough ER that lacks ribosomes.

Golgi Apparatus Functions

Modifies ER proteins, manufactures polysaccharides, and contributes to the plasma membrane.

Plant Central Vacuole

A large storage vacuole maintaining plant turgor pressure and structure.

Mitochondrion Function

Phosphorylates ADP into ATP to supply cellular energy.

Mitochondrial Endosymbiosis Evidence

Circular DNA, prokaryotic-like ribosomes, and prokaryote-like replication, prokaryote-like protein synthesis

Not in animal cells

chloroplasts, central vaccuole, tonoplast, cell wall, plasmodesmata

Not in plant cells

lysosomes, centrioles, flagella

Lyosomes

flow or connection of organelle membranes in formation of lysosomes

vesticles & vaccuoles

membrane board compartments used for storage

vaccuoles

larger than vesicles

all cells have…

plasma membrane, chromosomes, and ribosomes

nuclear envelope

has double membrane

pore complex

intricate protein structure

histones

small, basic proteins

chromatin

complex DNA + proteins

Ribsomes build proteins in 2 locations:

free ribsomes in cytosol, bound ribsomes outside ER

vesicle

sacs made by membrane

endomembrane system

nuclear envelope, lysosomes, various kind of vesicles & vaccuoles, plasma membrane, ER, Golgi apparatus

Detoxification

adding hydroxyl groups to drug molecules, making it more water soluble and easier to flush from body

glycoproteins

proteins with Carbohydrates covalently bonded

Golgi apparatus

warehouse for receiving, sorting, shipping, packaging, proteins are modified

Golgi removes

sugar monomers, substitute others, produces large amounts of carbohydrates, manufactures macromolecules

Lysosome

membrane sac of hydrolytic enzymes used to digest macromolecules, work best in acidic environments

Excessive leakage (large quantity of lysosomes)

Destroys the cell and self-digestion

Macrophages

type of white blood cell, helps defend body, engulfing and destroying bacteria

Tay-Sachs Disease

lipid-digesting enzyme that misses/inactive causes the brain to become impaired by accumulation of lipids

Food vaccuoles (formed by phagocytosis)

vaccuoles store poisonous or unpalatable compounds

peroxisome

oxidative organelle, specialized membrane component by single membrane, contains enzymes to remove hydrogen atoms from certain molecules, transfer oxygen into hydrogen peroxide

autophagy

hydrolytic enzyes that recycle cell’s own organic molecules

cristae (mitochondria)

enhances production of cellular respiration

mitochrondrial matrix (2nd)

the gel-like fluid space enclosed inside the inner membrane of a mitochondrion, contains different enzymes and mitochrondrial DNA and ribsomes

cytoskeleton

resambless in new location and changes shape of the cell

cell motility

both changes in cell location and more limited movement of cell parts

cytoplasmic streaming(circular flow of cytoplasm within cells)

speeds up movement of organelles and distribution of materials within the cell

primary cell wall

the thin, flexible, and extensible outer layer of a plant cell wall that forms while the cell is still growing

secondary cell wall

thick, rigid wall between plasma membrane and primary wall

extracellular matrix (animal cells)

the thin, flexible, and extensible outer layer of a plant cell wall that forms while the cell is still growing