Anatomy and Physiology - Cells

Nucleus

Stores DNA, DNA is packaged with protein and can be found in two forms: chromatin and chromosomes

Rough ER

Ribosomes are attached to the surface and make proteins that will be shipped out of the cell

Smooth ER

Lacks ribosomes, synthesizes important lipids, enzymes aid in detoxification

Golgi apparatus

After leaving the ER, transport vesicles travel here, products of the ER are modified, sorted, and packaged in new vesicles

Peroxisome

Membrane sacs that contain catalase and oxidase (smaller than lysosomes, abundant in liver cells)

Lysosomes

Membrane sacs that contain hydrolytic enzymes

Mitochondria

Power house of the cell, the sit of cellular respiration where ATP synthesis occurs

Ribosomes

Carries out protein synthesis, made of protein rRNA (not membrane bounded, not considered organelles)

What are transport vesicles? From what structures in the cell can they originate?

small, membrane-bound sacs that serve as the cell's delivery system, originate from the budding of membranes from organelles like the Endoplasmic Reticulum (ER) and the Golgi apparatus

Nucleolus

A small dense spherical structure in the nucleus of a cell during interphase

Nuclear pore

A minute opening through the nuclear envelope

Nuclear envelope

Encloses the nucleus separating its contents from the cytoplasm

Hypotoninc

A solutions solute concentration is less than that of the cell (cell gains excess water)

Hypertonic

A solution’s solute concentration is greater than that of a cell (cell loses water)

Isotonic

The solute concentrations of two solutions are equal, so no net water movement will occur

Receptor-mediated endocytosis

The cell brings in specific particles (ligands) that must first bind to special receptor proteins on the plasma membrane

Endocytosis

The cell’s engulf a large substance by forming a vesicle around it made from plasma membrane (pinocytosis, phagocytosis, receptor-mediated endocytosis)

Exocytosis

A vesicle inside the cell fuses with the plasma membrane and its contents are released out of the cell

Diffusion

Solute particles move from an area of high to low concentration (ex. passive transport particles move down the concentration gradient with no energy required)

Facilitated diffusion

Molecules move across the plasma membrane from high to low concentration with the help of a channel or carrier protein

Osmosis

The movement of water across a membrane from an area of high to low (water) concentration

Active transport

Molecules are moved against their concentration gradient and travel from low to high concentration

Filtration

Occurs when small molecules are forced through a porous membrane by hydrostatic pressure

G1

Cell grows and duplicates organelles

S

DNA is replicated (second sister chromatid created)

G2

Cell grows and prepares for division

M

Cell division (mitosis) and (cytokinesis) divison of cells cytoplasm

Prophase

Centrosomes move to opposite poles of cell and the mitotic spindle begins to form, chromatin condenses into chromosomes. nuclear envelope breaks down

Metaphase

(longest mitotic stage) all chromosomes are attached to two spindle fibers (from opposite poles), chromosomes line up at the metaphase plate

Anaphase

Sister chromatids separate and move toward opposite poles of the cell, cell begins to elongate

Telophase

Nuclei begin to form in daughter cells, chromosomes condense back into chromatin, mitosis is complete

What occurs during cell differentiation?

An immature cell develops into a specialized cell type with a distinct structure and function

Why is mitosis important to the human body?

Embryonic development, normal growth, repair of damaged tissues, replace dead or worn out cells

What happens during cytokinesis?

Divide the cell’s cytoplasm between the two daughter cells, a cleavage furrow forms at the surface of the cell and pinches the original cell in two

Which of the phases of the cell cycle make up interphase?

G1 phase, S phase, G2 phase

What occurs during transport system that is the sodium potassium pump?

A crucial active transport mechanism and maintains membranes potential in our cells

List the four components of the generalized human cell

Nucleus, cytoplasm, cytoplasmic organelles, plasma membrane

What is happening to a cell in the G0 phase?

Cells divide during embryonic development and once formed, they never divide again

Selective permeability

Some things pass through the plasma membrane easily and some do not (hydrophobic pass easily, hydrophilic do not)

Structure of the plasma membrane

Composed of a bilayer of phospholipids with proteins dispersed throughout

Which phases of the cell cycle contain checkpoints?

G1 (most important), G2, M phase

Pinocytes

Cell drinking, where the vesicles contains

Phagocytosis

Cell eating the cell engulfs particulate matter

What are cancer cells?

free from the body’s regular controls, have chromosomal and metabolic abnormalities, often grow via their own blood supply, lose attachment to nearby cells