Cell Vocab

cytology

the study of cells

plasma membrane

composed of a phospholipid “bilayer”

→ containing proteins

→ fluid mosaic model

phospholipids

essential lipid molecules that form the structural foundation of cell membranes, consisting of a hydrophilic head and two hydrophobic fatty acid tails.

hydrophilic

opposite of hydrophobic

• water loving!!

• substance/molecule that has a strong affinity for water

• can dissolve in or mix with water

hydrophobic

• substances or molecules that repel water and do not mix with it

• oils!!! → formation of cell membrane

fluid mosaic

The fluid mosaic model describes the structure of the cell membrane as a fluid lipid bilayer with embedded proteins

• phospholipids forming a bilayer, with hydrophilic heads facing outwards and hydrophobic tails facing inwards.

• Proteins, glycolipids, glycoproteins, and cholesterol are part of this diverse "mosaic".

selectively permeable

The plasma membrane is selectively permeable

• some things pass easily (small or uncharged) and others cannot pass through (large or charged molecules)

active transport

• uses cell energy (ATP)

• can move molecules against gradient

passive diffusion

• does not require cell energy

• moves from high to low concentration

osmosis

movement of H2O from high to low H2O concentration

facilitated diffusion

specific molecules attach to proteins and then they can diffuse through a membrane

organelle

specialized subunit within a cell that performs a specific function

chromatin

the material of which the chromosomes of organisms other than bacteria (i.e., eukaryotes) are composed.

• protein, RNA, and DNA.

vesicles

small fluid-filled bladder, sac, cyst, or vacuole within the body

peroxisomes

membrane bound organelles found in the cytoplasm of most eukaryotic cells

• lipid metabolism

• conversion of reactive oxygen species

ATP

molecule that supplies energy directly to a cell

microvilli

microscopic, finger like projections found on surface of certain cells

→ epithelial cells

• increasing the surface area for absorption and secretion

cilia

small, hairlike structures found on the surface of eukaryotic cells

• locomotion, can be involved in moving fluids across the cell surface

• motile + nonmotile