A&P1_Chapter3.txt

Three types of Microscopes used to study cells are the compound light microscope, the transmission electron microscope (TEM), and the scanning electron microscope (SEM.)

• a. The plasma membrane is the outer layer of the cell, primarily made if lipids and proteins.
• b. The function of the plasma membrane is to enclose the cell contents, regulate what enters and leaves the cell, participates in growth and reproduction, and is involved in cellular interactions.

a. The cytoplasm is the material that fills the cell from the nuclear membrane to the cell membrane. Within the cytoplasm of the cell are several main organelles:

• i. The endoplasmic reticulum (ER) sorts proteins and forms them into more complex compounds. Smooth ER is involved with lipid synthesis.
• ii. The Mitochondria are large organelles that are round or bean shaped with folded membranes on the side and convert energy nutrients into ATP.
• iii. The Golgi apparatus is a stack of membranous sacs involved with sorting and modifying proteins and then packaging them for export from the parts of or outside of the cell.

DNA is located almost exclusively located in the nucleus of a cell with the exception of a small portion located in the mitochondria within the cytoplasm. It is comprised of four nucleotides (Adenine, Guanine, Cytosine, and Thymine) and is responsible for all hereditary units that control all cell activities. They also divide into genes, which carry the nucleotide codes for the manufacture of proteins.

• a. Messenger RNA (mRNA) describes the nucleotide code and moves to cytoplasm and attaches to a ribosome.
• b. Ribosomal RNA (rRNA) translates the genetic message into a protein.
• c. Transfer RNA (tRNA) works with other forms of RNA to translate the genetic code into protein but also carries an amino acid that can be used to build a protein at the ribosome.

The DNA in a cell nucleus separates its weak bonds and is transcribed into mRNA through nucleotide base pairing, known as transcription. The mRNA moves to the rRNA and transcribes the code to build amino acids, which will then be assembled by the tRNA to make proteins.

• a. The primary stage of a cell is interphase, which is when the cell performs all the functions it was created to do to support the body.
• b. Prophase occurs when the nucleolus and nuclear membrane begin to disappear and the two centrioles move to the opposite ends of the cell and a spindle-shaped structure made of fibers begins to form between them
• c. In Metaphase, the chromosomes line up across the center of the cell attached to the spindle fibers.
• d. During Anaphase, the centromere splits and the duplicate chromosomes separate and move to opposite ends of the cell.
• e. Mitosis continues into telophase when a membrane appears around each group of separated chromosomes, forming two new nuclei.

• a. Diffusion is the random movement of particles with a concentration gradient until they reach equilibrium. This requires no cellular energy
• b. Osmosis is the diffusion of water though a semi-permeable membrane
• c. Filtration is the movement of materials through a membrane under mechanical force, which would be the force of blood pressure.
• d. Facilitated diffusion is the movement of materials through the plasma membrane along the concentration gradient using transporters to speed the process.
• e. Active Transport is the movement of materials through the plasma membrane against the concentration gradient using transporters.
• f. Excoytosis transports bulk amounts of materials out of the cells using vesicles
• g. Endocytosis Transports bulk amounts of materials into the cell using vesicles. This is further broken down into:
• i. Phagocytosis – large particles engulfed by a plasma membrane are moved into the cell.
• ii. Pinocytosis - the plasma membrane engulfs droplets of fluid. This is a way for large proteins molecules in suspension to travel into the cell.

• a. If cells are places in an isotonic solution (solutions with and equal concentration to the concentration of cytoplasm in the cell) nothing abnormal happen.
• b. If cells are placed in a hypotonic solution (solutions with less of a concentration to the concentration of cytoplasm in the cell) cells may undergo hemolysis, where they draw in water, swell, and burst.
• c. If cells are placed in a hypertonic solution (solutions with more of a concentration to the concentration of cytoplasm in the cell) cells may undergo crenation, and will lose water to the surrounding solution and shrink.

• a) Bacteria
• b) Protozoa

• can live independantly of other cells
• cells make up all tissues
• all activites in the human boday result from the activities in human cells

• a) Plasma membrane
• b) Nucleus
• c) Cytoplasm
• d) Organelles

• a) it encloses the cell and partisicpates in growth and reporoduction
• b) involved in cellular interactions
• regulates what enters and leaves the cell

• a) May be folded into small projections called microvilli which act to increase surface area
• i. lining the small intesting and kidney cells
• ii. greater abnsorbtion of materials from environment
• b) Phosphlipid bilayer
• c) cholesteral - strengthens the mebrane
• d) Carbohydrates - helps cells recognize each other
• i. combined with protiens (glycoprotiens and glycolipids
• e) protiens
• - channels
• - transporters
• - receptors
• - enzymes
• - linkers
• - cell identity markers

• - channels: allow specific ions to enter or leave
• - transporters: shuttle substances across the membrane
• - receptors: act as points of attachment for materials that act on a cell
• - enzymes: participate in reactions occuring at the plasma mnembrane
• - linkers: give structure to the membrane and help cells attach to each other
• - cell identity markers: are proteins that are unique to an indiviuals cells. important to immunity and tissue transplants

• - the control center of the cell
• - contains the chomosomes with govern all cellular activities
• - nucleolus contains RNA, DNA and protiens tha man ufacture ribosomes in the cytoplasm
• - Almost all DNA is found in the cell nucleus

• colloidal suspension that fills the remainder of the cell
• cytosol - liquid part of cytoplasm containing nutrients and organelles
• Organelles - specialized structures that perform different tasks for the cells

• Endoplanmic recticulum - network of membranes that is either smooth or rough
• - smooth ER - involved with lipid synthesis
• - Rough ER - comes from ribosomes attached to the ER
• Ribosomes - necessary for protien synthesis and are either attached to the ER or floating free
• Mitochondria - converts nutreints to ATP, the powerplant fo the cell
• Golgi Apparatus - involved with sorting and modifying protiens and packing them for export from the cell
• centrioles - near the nucleus; help organize the cell and divide the cell contents during the process of cell division
• Lysosomes - remove waste and foriegn materials from the cells
• Peroxisomes - destroy byproducts of metabolism
• Vesicles - Storage units of the cell, can also move materials into and out of the cell

• network of membranes that is either smooth or rough
• - smooth ER - involved with lipid synthesis
• - Rough ER - comes from ribosomes attached to the ER

- necessary for protien synthesis and are either attached to the ER or floating freeMitochondria - converts nutreints to ATP, the powerplant fo the cell

- involved with sorting and modifying protiens and packing them for export from the cell

- near the nucleus; help organize the cell and divide the cell contents during the process of cell divisoin

- remove waste and foriegn materials from the cells

destroy byproducts of metabolism

- Storage units of the cell, can also move materials into and out of the cell

• Cilia - cmall hairtlike projections that wave creating movement of fluids around the cell. respiratory passage cells and female reproductive tract cells have them
• Flagellum - long whip like enxtensions used for movement. only male sperm have them

• size - average anywhere from 10-15 micrometers
• RBC are small (7 micrometers)
• muscle cells are big (200 micrometers)

• Hereditary units that govern the cells
• 23 pair
• 46 in total

divided into genes.

The carry messages fro the development of particular inherited characteristics and do so by directing the manufacture of protiens within a cell

Nucleotides

DNA

related compound to DNA but is not part of the chromosome but still participoates in protien synthesis

• Adenine (A)
• Guanine (G)
• Cytosine(C)
• Thymine (T)
• A & T are paired. C & G are paired

• Adenine (A)
• Guanine (G)
• Cytosine(C)
• Uracil (U)
• A & U are paired. C & G are paired

• Sugar - RND and DNA
• Phosphate -
• Nitrogen Base

• 
• Nitrogen bases are the steps
• 2 DNA strands make a pair
• 2 DNA strands are bonded together with Hydrogen bonds to form a double helix

• cellular division
• DNA must replicate completely before splitting

• Interphase
• Prophase
• Metaphase
• Anoaphase
• Telophase - remember cleavage furrow

• diffusion
• osmosis
• filtration
• facilitated diffusion
• active transport
• exocytosis
• endocytosis
• - phagocytosis
• pinocytosis

• diffusion
• osmosis
• filtration
• facilitated diffusion

• exocytosis
• endocytosis
• - phagocytosis
• - pinocytosis