Cell

Cells

smallest structural units that perform vital functions

Do cells have specialization

Yes they do one more more functions more effectively

Cells 2 major compartments

cytoplasm and nucleus

How are cells shape determined

cytoplasmic skeleton

plasma membrane purpose

separate cytoplasm of cell from extracellular world

Plasma membrane composition

lipid bilayer with hydrophobic inner layer with proteins (integral and peripheral)

Plasma Membrane what is on extracellular surface

glycoproteins, glycolipids, that form glycocalyx which is a cell coat

What does plasma membranes do

signaling hubs, bringing receptors and signaling molecules together for efficient communication

What is plasma membrane composed of

phospholipids and cholesterol

Two types of membrane proteins

integral (embedded) or peripheral proteins (loosely attached)

Two types of vesicular transport

Endocytosis (substance in) vs exocytosis (substance leaves)

phagocytosis

engulf solid particle

Pinocytosis

take in fluid

Receptor-mediated endocytosis

targets specific molecules using membrane receptor proteins

3 types of signaling

endocrine, paracrine, and synaptic

Endocrine signaling

Involves hormones

Paracrine signaling

affects nearby cells

synaptic signaling

involves neurotransmitters

Mitochondria present in what

all RBCs except terminal keratinocytes

Why folds in mitochondria

allow for more surface area

What cells have a lot of mitochondria

cells that require a lot of energy like muscles

Ribosomes purpose

assemble proteins and made in ER

Endoplasmic Reticulum

network of interconnecting channels forming the cisterna which run through cytosol

Golgi Apparatus

shipping and modification

Diff between free and ER-bound polyribosomes

Free’s proteins stay in cell while ER bound leaves

What happens to bad proteins

ERAD (endoplasmic-reticulum associated protein degradation)

Secretory granules

Lysosomes: intracellular digestion

Peroxisomes

Oxidize substrates

Cytoskeleton function

• determine shape of cells

• movement of organelles

• movement of the cell

cytoskeleton components

microtubules, microfilaments, intermediates filaments

Microtubules

form near nucleus and create a system of connections within cells

microfilaments

actin filaments are in all cells and grouped in bundles

microfilaments cell function

• anchorage and movement of membrane proteins

• form structural core of microvilli

• extension of cell processes

• movement of cell

Intermediate filaments role

support and strucutural

Intermediate filaments 4 major classes

Keratin, Vimentin, neurofilaments, Lamins

Nuclear envelope

bilayer with space in between and has openings called nuclear pores

Chromatin

chromosomal material

Nucleolus

sit of rRNA synthesis

Stem cell division

one stays stem cell the other is differentiated