Unit 3: Cells

nucleus

nucleus

This part of the cell is the headquarters, the control center

nuclear envelope, nucleolus, chromatin

what are the 3 parts of the nucleus?

nuclear envelope

this defines the nucleus and is selectively permeable

nucleolus

this is the “little nucleus” and produces ribosomes

chromatin

these are threads of DNA and protein that will eventually become chromosomes

hydrophilic

are phospholipid heads hydrophobic or hydrophilic?

hydrophobic

are phospholipid tails hydrophobic or hydrophilic?

bi-lipid layer

2 lipid layers that contain phospholipids, proteins, and cholesterol

glycoproteins

“sugar proteins” - function as receptors to sugars

globular proteins

these create pores in the membrane

cytosol

fluid inside cells

organelles

functional parts of cells

inclusions

cell specific substances

cytosol, organelles, inclusions

what three parts make up cytoplasm?

mitochondria

center for cell respiration - makes energy

cristae

membrane inside the mitochondria that increases surface area

ribosomes

site of protein synthesis

endoplasmic reticulum

provides a passageway through the cell and increased surface area for more chemical reactions

rough ER

makes and stores proteins, has ribosomes on it

smooth ER

makes and stores lipids, no ribosomes

golgi apparatus

a stack of flattened membranes that packages proteins and lipids for export

vesicle

created by the golgi apparatus to transport proteins or lipids

lysosome

cleans the cell, vesicle that contains powerful digestive enzymes

centrioles

tubes at right angles to each other that function in cell reproduction

microfilaments

thin rods of protein, used for cellular movement

microtubules

thick tubes of protein that provide internal framework for the cell and intracellular transportation

peroxisomes

these disarm dangerous free radicals

cilia

sweep substances across the cell surface

flagellum

long tail that propels the cell

microvilli

absorb nutrients into the bloodstream in the small intestine

inclusions

non-functioning units, but essential for various functions

interstitial fluid

what are cells surrounded by?

selectively permeable

the cell membrane is this which means it only allows some solutes to pass through freely

passive transport

molecules passing through the membrane without using the cell’s energy

active transport

cell uses energy to transport molecules through the membrane

diffusion

means of particle transport for every cell in the body - spreading from high to low concentration, move in random motion

equilibrium

when equal amounts of particles are moving in opposite directions

fats, gases, water

what three things can diffuse through the cell membrane?

osmosis

the diffusion of water (high to low concentration)

hypertonic solution

high solute concentration, low water concentration, water diffuses out of the cell

crenation

cell shrinking

hypotonic solution

solute concentration low, water concentration high, water will diffuse into the cell

cytolysis

cell swells/ruptures

isotonic solution

solute concentration is equal inside and outside cell, water diffuses in and out equally

facilitated diffusion

sugars diffuse through cell with help from proteins

filtration

water and solutes filter out of the blood into tubes because of high pressure in the kidney’s capillaries

low to high concentration

in what way do particles move in active transport?

sodium-potassium pumps

protein pumps move sodium ions out and potassium ions in, against the gradient

nerve impulses

what are sodium potassium pumps important for?

exocytosis

leaving the cell - secrete hormones, mucus, and wastes

endocytosis

entering the cell

pinocytosis

cell drinking (fluids)

phagocytosis

cell eating (bacteria)