lab manual exercise 4 &5

nucleus

contain DNA (control center) which is necessary for reproduction

threadlike genetic material

chromatin which is loosely dispersed when not dividing

chromsomes

chromatin condense and coil to form a dense, rodlike bodies

nucleoli

compose of protein and RNA (assemble site for RNA)

nuclear envelope

double layer porous membrane

nuclear pore

spanned by protein complexes that regulate what passes through (protein & RNA)

plasma membrane

separate cell content from surrounding environment / providing a protective barrier

what does plasma membrane structured

phospholipids (fats) and globular protein

what is dispersed in the bilayer for stabilize

cholesterol

selective permeability

selective for what goes in and out of the bilayer

intergral protein

create channel for molecules and binds signal molecules (hormones)

glycocalyx

allows cells to adhere and provide protection.

also allows binding of signal molecules

glycolipid

maintain stability and recognition of signal molecules

glycoprotein

recognition of signal moleucles

peripheral protein

regulate the transportation of molecules

inclusion

storage site for nutrients and waste

ribosome

consist of RNA & protein (actual site of protein synthesis )

Rough ER

studded with ribosomes

store and transport protein

Smooth ER

site of steroid and lipid synthesis, lipid metabolism and drug detoxification

Golgi apparatus

packing protein and other substance in lysosomes enzyme to export

lysosomes

contain digestive enzymes

peroxisomes

contain oxidase enzymes that detoxify harmful chemicals

mitochrondria

double layered membrane with folds (Cristal) and enzymes to produce ATP

centrioles

paired, each contain nine triplets of microtubules.

direct the formation of mitosis spindle and form cilia and flagella (b(basal bodies)

cytoskeletal

an internal scaffolding that provides cellular support

microfilament

actin (contractile protein) for cell mobility

intermediate filament

stable element composed of proteins and resist mechanical forces on cell

microtubules

form the internal structure of centrioles and help determine cell shape

mitosis (diploid)

cell reproduction of 2 genetically identical daughters

cytokinesis

division of cytoplasm

what happen if cytokinesis did not occur

it will form multinucleate cells

meiosis (haploid)

reproduction of gametes with 4 genetically different daughters

phases of mitosis

1. prophase

2. metaphase

3. anaphase

4. telophase

centriole replication

occurs during the interphase of the next cell cycle

interphase

cells carry out normal metabolic and grows

G1 phase

centrioles begin to replicate

synthesis phase

DNA is replicated

G2 phase

centrioles finish replication

what happens to the chromatin in early prophase

chromatin condense to form chromosomes

each duplicated chromosomes consist identical sister chromatids held together at centromere

what happen to nucleoli in early prophase

nucleoli disappear

centrosomes

act as a final point for growth of mitotic spindles

as microtubules lengths, centrosomes pushes towards the opposite end

asters

microtubules array extend from centrosome matrix

late prophase

nuclear envelope breaks up, allow spindle to interact with chromosomes

kinetochores

a protein structured at centromere

spindles (kinetochore microtubules) attach to kinetochores

nonkinetochore microtubules

slides past each other forcing poles apart

metaphase

chromosomes aligned at the metaphase plate

enzymes separate chromatids from each other

anaphase

chromatids are pulled towards opposite sides

telophase

chromsomes uncoiled and nuclear envelope reform

nucleoli reappear and spindle breaks down

cytokinesis

a contracile ring of actin microfilament forms cleavage furrow and pinches the cell apart

passive transport

concentration or pressure difference drive the movement

active transport

cells provides ATP to power transport process

two types of passive transport

simple diffusion and filtration

filtration occurs at

usually across capillary walls

How do molecules move

possess kinetic energy, moves randomly at high speed

concentration gradient

uneven of concentration distribution

Diffusion

movement of molecules from hight to low concentration

what does the speed of diffusion depends on

molecules size (low= faster) and temperature (high=faster)

simple diffusion

allow dissolved lipid solutes to pass through

facilitated diffusion

transported across plasma with assistance of protein carrier

osmosis

flow of water across semipermeable membrane from low to high concentration

water and solute relation

concentration of water is inversely related to concentration of solute

filtration

solute and water are forced through membrane by hydrostatic pressure

what does filtration depend on

pressure gradient and size of membrane pores

isotonic solution

same solute concentration

hypertonic solution

cell lose water (higher conc. of solute in cell)

hypotonic solution

bloated (less solutes in the cell)

hemolysis

the rupture of red blood cell as water flood in

molecules of active transport

too large and not lipid soluble

types of active process

active transport and vesicular transport

active transport requires

carrier protein

primary active transport

driven by the hydrolysis of ATP

secondary active transport

driven indirectly by the energy stored in ionic gradient

active transport moves

against gradient (high to low )

vesicular transport

large particles and macromolecules transported insides vesicle

endocytosis

movement of vesicle into the cell

exocytosis

movement of vesicles outside the cell

vesicular transport requires energy

ATP hydrolysis to ADP

3 types of endocytosis

phagocytosis

pinocytosis

receptor-mediated endocytosis

phagocytosis

engulf cell debris,bacteria and others

pseudopods

when a particle binds to receptor, cytoplasmic extension form to produce phagosomes

phagosomes

vesicles that fuses with lysosomes and digested

non digested are ejected through exocytosis

pinocytosis (cell-drinking)

cell gulps a drop of extraceullar fluid containing dissolved material

receptor-mediated endocytosis

molecules bind to specific receptor on plasma

allows cell to concentrate molecules in small amt in extracellular fluid

allow selectivity

ingested material may fused with lysosomes

exocytosis

eject substances from cell which was enclosed in secretory vesicles