anaphy lab: cells

cell/plasma membrane

• outermost layer of the cell

• “gatekeeper” of the cell

• is selective in what it allows into or out of the cell

• interface between the internal and external environment of the cell

phospolipids bilayer, proteins, cholesterol, other molecules

the plasma membrane is composed of a ____________

cholesterol molecules

• provide stability to the membrane or, in larger concentrations, make the membrane more fluid

hydrophilic and hydrophobic

phospolipids consist of a ________ phosphate group attached to a _________ lipid groups

peripheral proteins

proteins found in the membrane that are on the inner/outer surface

integral proteins

those proteins that passing into the membrane

Cytoplasm

• most of the inside of the cell

• portion of the cell in which watee, dissolved magerials and small cellular organelles are found

cytosol

• fluid in which the organelles are suspended

• the inner fluid portion of the cell

• composed of water with dissolved materials, such as sugars, ions, proteins, and amino acids

cytoskeleton

• the framework of the cell

Microtubules

• made of protein tubulin and area approximately 25 nanometers (nm) in diameter

Microfilaments

made of actin and are approximately 8 nm in diameter

Intermediate filaments

composed of fibrous proteins and are approximately 10nm in diameter

Organelles

• literally means “small organ”

membranous and non-membranous

two (2) types of organelles

Mitochondria (plural), Mitochondrion

• rod-shaped organelles eith a rouble membrane

• major function is to convert the stored chemical energy in food molecules to store chemical energy in molecules of adesonine triphosphate (ATP)

Ribosomes

• are the smallest of the organelles (about 25nm in diameter) and are non- membranous

• main function is to produce proteins

Endoplasmic Reticulum (ER)

• an organelle composed of anetwork or enclosed channels

• have two types

Rough Endoplasmic Reticulum (RER)

• associated with the nucleus and produces proteins for transport and use outside the cell

Smooth Endoplasmic Reticulum (SER)

• produces lipid compounds (including phospolipids and steroids) and detoxifies material.

Golgi Apparatus

• receives material from the endoplasmic reticulum and other parts of the cytoplasm snd serves as an assembly and packaging organelle

cisternae

golgi apparatus has ________, which are flattened, membrous sacs, and it forms vesicles to transport the molecules it assembles.

1. Nucleus

2. Chromatin

1. _____________

has (2) functions:

• to house the genetic information if the cell

• to direct mang cellular functions

2. _____________

these 2 functions are carried out by the (deoxyribonucleic acid) DNA which combines with proteins to form a material called _________ in the nucleus

Nuclear Envelope

• contain nuclear pores, which allow the movement of materials into or out the nucleus

Nucleoli

• consists of portion of chromosomes and thus cintain DNA and proteins.

• they make rRNA, which forms ribosomes.

Ribosomes

• the protein-producing organelles in the cytoplasm of the cell

Vesicles

• are membrane-bound savs inside the cell

• they digest sub-cellular material out of the cell, and carrycl on enzymatic activities

• can fuse eith other organelles or the plasma membrane; thus they protect the integrity of the plasma membrsne

• it fuses with the plasma membrane, ejecting fhe ladger molecules without disrupting the plasma membrane

• has two: lysosomes and peroxisomes

Lysosomes

• digest material with enzymes in a orocess known as phagocytosis, also known as phagocytic vesicles

Peroxisomes

• use enzymes to convert potentially toxic hydrogen peroxide to water and oxygen.

Cilia

• hair-like strictures found in the cells that are involved in movement of mucus along the respiratory passge

• most cells have this

• consists of microtubules covered by the plasma membrane

Flagella

• found only in the sperm cells

• tail/whip-like structures

• also consists of microtubules covered by the plasma membrane

Centrosomes

• typically found close to the nucleus and contain centrioles, which play a part in microtubule formation

• also involved in the formation of a structure called spindle apparatus, which is associated with cellular division

Microvilli

• small extensions of the surface of some cells rhat are involved in the absorption of material (such the digestive/urinary system)

cell cycle

when cells produce more cells, it’s a process known as

interphase and cell division

cell cycle divided in to two(2) stages

Interphase

• stage of the cell cycle where it is the time when a cell undergoes growth and duplication of DNA in preparation for the next cell division

• has three phases known as the G¹ phase, S phase, G² phase

1. G¹ phase (gap1)

2. S phase (synthesis)

3. G² phase (gap2)

______ phase - cells are growing in size snd producing organelles

______ phase - the DNA of the cell is duplicated. the double-helix of the DNA molecules unzips and two new, identifal DNA molecules are produced.

______ phase - the cell continues to grow and prepares for the process of mitosis

Mitosis

• is a continous event divided into five distinct phases.

• is a nuclear division of genetic information to produce two identical nuclei.

prophase, prometaphase, metaphase, anaphase, telophase

five phases of mitosis

Prometaphase

• in this phase of mitosis, the spindle fibers, which are microtubules, attach to the chromosomes at the centromere

Prophase

• condensation of chromatin into chromosomes

Metaphase

• in this phase in mitosis, the chromosomes align between the poles of the cell in a region known as the ______ plate

Anaphase

in this phase in mitosis, the chromosomes seperate at rhe centromere, and each chromatid is known as a daughter chromosome.

Telophase

• in this phase in mitosis, once the daughter cellls resfh the poles, the phase begins.

• the daughter chromosomes begin to unwind into chromatin, fhe nucleolus reappears, and the nuclear envelope begins to reform. the mitotic apparstus disassembles, terminating the mitosis

Cytokinesis

• splitting if the cell’s cytoplasm into two parts

Diffusion

• movement of particles from regions of high concentration to low concentration

concentration gradient

• difference between the two concentrations is known as

equilibrium

if particles become uniformly dispersed, the system has reached __________

Osmosis

• movement of water across a selectibely permeable membrane from regions of higher water concentration fo lower concentration

cytology

scientific study of cells