Ch2 cells

Obtain nutrients

rid of wastes

•Shape and integrity

•Functions and characteristics determined by the genetic material

•Most cells capable of cell division

Light microscopy (LM)

•Visible light passes through the cell

Transmission electron microscopy (TEM)

electrons passes through

•2D image

Scanning electron microscopy (SEM)

•Beam of electrons bounces off surface of cell

3D image

Covering

Lining

Storage

Movement

Connection—

Defense—

Communication—

Reproduction—

•Separates intracellular fluid (ICF) from extracellular fluid (ECF)

Lipids

•Phospholipids (hydrophilic head and hydrophobic tails)

•Cholesterol- against extreme temperature

•Glycolipids- Have carbohydrate groups attached

•Sugar groups face outward,helping form glycocalyx

Proteins

•Integral

-Span entire membrane, may have membrane channels and receptors

-May have carbohydrates attached = glycoproteins

•Peripheral

-Loosely attached

External to the plasma membrane is a carbohydrate (sugar) coat called the glycocalyx

-Transport—movement of material across the PM;

-Intercellular connection—

Anchorage for the cytoskeleton—

-Enzyme (catalytic) activity—affect the rate of chemical reactions; example = ion pumps moving ions across the membrane

-Cell–cell recognition—glycoproteins aid in cell identification

-Signal transduction—message

Transport proteins help move large/polar molecules across membrane down their concentration gradients(passive)

Hydrostatic pressure pushes substances across membrane

•Both solvents and solutes transported together(passive)

•Move ions against gradient

•Example: sodium-potassium pump

active transport

Exocytosis: secreted out of cell

Endocytosis: materials taken into cell,

-Phagocytosis "eating"(pseudopodia, extensions)

-pinocytosis "drinking"

-receptor-mediated endocytosis-  receptors on the pm

•Cytosol- Ions, Nutrients, Proteins, Carbohydrates, Lipids

•Inclusions- ex melanin, glycogen, Protein crystals

•Organelles

Membrane-bound endoplasmic reticulum, Golgi apparatus, lysosomes, peroxisomes, mitochondria

Nonmembrane-bound  ribosomes, cytoskeleton, centrosomes, centrioles, cilia, flagella, microvilli

Synthesis, transport, and storage of lipids including steroid hormones

•Detoxification of drugs, alcohol, and poisons

Rough ER

parallel membranes enclosing spaces called cisternae

modifies proteins and packages them into transport vesicles

receives material from the ER for modification, sorting, and packaging

-stacked cisternaeLateral edges pinch off, and give rise to small transport and secretory vesicles

•Receiving region is the cis-face

•Shipping region is the trans-face

1. Proteins synthesized in RER packaged into transport vesicles

2. Transport vesicles pinch off from RER and fuse with receiving region of Golgi apparatus

3. Proteins move between and are modified in the cisternae of Golgi apparatus

4. Modified proteins are packaged in secretory vesicles

5. Vesicles leave shipping region of Golgi to become secretory vesicles(exocytosis), part of plasma membrane, or lysosomes

Contain enzymes used to digest and remove waste products and damaged organelles within the cell (autophagy)

When a cell is dying, it releases lysosomal enzymes that digest the cell (autolysis)

protein synthesis

Free ribosomes in the cytosol

Bound ribosomes attached rough ER

•Microfilaments -actin proteins intertwined in helical strands

•Intermediate filaments- stabilize junctions between apposed cells

•Microtubules-Radiate from centrosome, Direct movement of organelles in the cell

Centrosome:

•adjacent to nucleus, pair of centrioles

Centrioles:

nine sets of microtubule triplets

•Attached to chromosomes during cell division

nuclear envelope(double membrane)

nucleoli- dark-staining bodies, RNA, enzymes, and various proteins

chromatin

G₁ phase

•Near end of G_1, cells replicate centrioles

S phase

•“Synthesis” phase where DNA replicates in preparation for cell division

G₂ phase

•Centriole replication is completed

•Organelles and enzymes needed for cell division are produced

division of the cytoplasm

 prophase, metaphase, anaphase, telophase

Chromatin -> chromosomes (identical sister chromatids are joined at centromere

•Replicated (double-stranded) chromosomes because DNA was copied in interphase

Elongated microtubules called spindle fibers grow from each centriole

The end of prophase is marked by dissolution of nuclear envelope

Chromosomes line up along equatorial plate

Spindle fibers attach to centromeres of chromosomes and form an oval-structured array called the mitotic spindle

Spindle fibers pull sister chromatids apart

Each chromatid is called a single (single-stranded) chromosome

•Has own unique centromere

Nuclear envelopes form around each set of chromosomes

Cleavage furrow (indentation) appears as cytoplasm divides

•Necrosis = irreversible damage via harmful agents or mechanical damage

•Apoptosis = programmed cell death

glycolipids

integral, peripheral

catalysts