Cells pt2

What are the 3 intercellular junctions?

Tight junctions, Desmosomes, Gap junctions

What are tight junctions?

• close space between cells

• located among cells that form linings

What are desmosomes?

• form spot welds between cells

• located among outer skin cells

What are gap junctions?

• tubular channels between cells

• located in cardiac muscle cells

The cell membrane is also referred to as what?

plasma membrane

What does the cell membrane do?

Regulates passage of
materials in and out of cell

What is the cell membrane made out of?

phospholipid and proteins

Phosphate heads are what?

Hydrophilic / polar

Fatty acid tails are what?

Hydrophobic / nonpolar

A fluid mosaic w/ a double layer of phospholipids w/ embedded proteins

regulates exchange creates a barrier, allows communication identification

What is cytoplasm?

all the fluid and
organelles between the cell
membrane and the nucleus

What is cytosol?

Fluid in cytoplasm

Nucleus

Controls cell activities and
contains genetic material,
DNA

Nucleolus

Synthesis and storage of
RNA

Chromatin

Tangle of fine threads in a
non-dividing cell, uncoiled DNA when the cell is in
interphase

Chromosome

Tightly coiled DNA in a
dividing cell, when the cell
undergoes mitosis

Chromatin

A complex of DNA and proteins that forms chromosomes within the nucleus during cell division

Mitochondrion

site of cellular respiration, powerhouse/ produces atp

What is cristae?

A shelf like structure

What are centrioles?

Occur in pairs of 9 microtubule triplets

What is a centrosome?

The 2 centrioles

What is golgi body? EX?

Packaging and distribution center for products to be exported

Ex: glycoproteins & lipoproteins

Function of lysosomes

Digests food, cells, and organelles

Smooth ER

Transportation channels w/out ribosomes, site of lipid synthesis

Rough ER

Transportation channels w/ ribosomes

Ribosomes

Attached or free site of protein synthesis

Vacuoles

Storage and elimination, small in animal cells, large in plant cells

Microtubules

Cell skeleton, give cell shape, seen in cilia, flagella, and spindle fibers

Microfilaments

Cell muscle cytoplasmic mvt, help with cleavage furrow