Phospholipids are the major constituent of the membrane. It defines the perimeter of the cell and is involved in cell adhesion, cell signaling, and transport of materials in and out of the cell.

Cytoplasm - the entire contents of the cell, exclusive of the nucleus and bounded by the plasma membrane

In prokaryotes, it includes the entire contents of the cell. Many cell reactions take place here.

Cytosol - a semifluid substance in the cytoplasm

Organelle - a specialized subunit within a cell that has a specific function, usually enclosed by a membrane, ex. nucleus

Nucleus - contains the genetic material of a eukaryotic cell

Nuclear Envelope - encloses the nucleus, separating its contents from the cytoplasm

Nucleolus - a highly visible region in the nucleus where ribosome are assembled from rRNA and ribosomal proteins

Ribosome - Site of protein synthesis and composed of ribosomal RNA and protein

Free Ribosomes - produce proteins that will remain inside the cell

Rough ER Membrane-Bound Ribosomes - produces proteins destined for secretion and proteins destined for insertion into the cell membrane

Endoplasmic Reticulum - an interconnected system of tubules

It is connected with the nuclear envelope. There are two types...

Smooth Endoplasmic Reticulum - no attached ribosomes

Rough Endoplasmic Reticulum - ribosomes are attached

The ribosomes on the rough ER produce proteins that will be later inserted into the cell membrane or secreted from the cell.

Golgi Complex - modifies, stores, and routes proteins and other chemical products to their next destination

This is also known as the Golgi Apparatus or Golgi Bodies.

Lysosome - involved in the digestion of nutrients, harmful bacteria, and damaged organelles and Apoptosis

Apoptosis - programmed cell death

Cytoskeleton - consists of microtubules and microfilaments

It maintains cell shape, is an anchorage for organelles, and allows for the movement of organelles within a cell.

Centrosomes - the microtubule-organizing centers that form the mitotic spindle in dividing cells

Centrioles - animals have these within their centrosomes which help with cell division

Vesicles - small membrane-bound sacs that are used to move chemicals around the cell

Vacuoles - membrane-bound sacs that are larger than vesicles and have a diverse set of functions, ex. food vacuole stores food taken into the cell

Central Vacuole - only found in plant cells and its main role is to maintain turgor pressure against the cell wall

It also determines whether the cell is turgid or flaccid and is storage for nutrients and water.

Contractile Vacuole - maintains water balance by pumping the excess water out of a cell and is found in freshwater protists

Mitochondria - present in eukaryotic cells, double membrane, and is the major site where energy from food is used to make ATP which is needed to do cell work

Chloroplast - found in algae and plants, double membrane, green color, and photosynthesis occurs here

Cell Wall - found in plant cells, consists of cellulose, includes maintenance of cell shape and skeletal support and provides protection for plant cells

Flagella - tail-like projection that is involved in cell movement

Cilia - short finger-like projections that are involved in cell movement

Pseudopod - temporary cytoplasmic projections that allow cells to move or engulf food that is involved in cell movement

Types of Cells:

Prokaryotes - single-celled, smallest of the cells, lack a nucleus, lacks membrane-bound organelles, has a cell wall made of peptidoglycan, and has circular DNA, ex. bacteria and archaea

Eukaryotes - has a nucleus, has membrane-bound organelles, can be single or multicellular, and has linear DNA, ex. protists, fungi, plants, and animals

There are characteristics that all cells have...

Bounded by a plasma membrane, contains cytosol, contains chromosomes, and contains ribosomes.

Endosymbiosis - the evolution of eukaryotes, and the origin of mitochondria and chloroplasts

The origin of mitochondria happened because early eukaryotic heterotrophs engulfed aerobic bacteria but did not digest them. The origin of chloroplasts happened because some additional heterotrophs engulfed photosynthetic bacteria but did not digest them.

What is the Endosymbiotic Theory?

The Endosymbiotic Theory is that mitochondria and chloroplasts originated as separated organisms that were engulfed but not digested and a symbiotic relationship was developed.

Animal vs. Plant Cells...

There are three cell structures unique to plant cells, which are chloroplasts, the cell wall, and the central vacuole.

Level of Structure - Atom < Molecule < Organelle < Cell < Tissue < Organ < Organ System < Organism

Transport:

Phospholipid Bilayer - semi-permeable bilayer

Small hydrophobic molecules can get across, but hydrophilic can't.

Protein Channels - specific channels that allow hydrophilic materials across the cell membrane since the phospholipid bilayer won't let them

Cholesterol - prevents the cell membrane from becoming too rigid or too fluid and is important for membrane stability

Passive Transport - molecules move from areas of higher concentration to areas of lower concentration and no energy is required by the cell, ex. simple diffusion, facilitated diffusion, and osmosis

Simple Diffusion - molecules move from areas of higher concentration to areas of lower concentration, is passive, and increased temperature speeds up the rate of diffusion

Facilitated Diffusion - diffusion through transport proteins, and allows hydrophilic molecules to diffuse across the cell membrane

Osmosis - diffusion of water across a selectively permeable membrane from a high concentration to a low concentration

Water moves through a channel in the membrane called an aquaporin. Water moves to equalize the solute concentration inside and outside the cell.

Solvent - the substances that dissolve the other substance and are present in the greater amount

Solute - the substance that is dissolved and is present in the lesser amount

Solution - a mixture of one or more solutes dissolved in a solvent

Hypertonic - a solution with a higher concentration of solute and a lower concentration of water

Hypotonic - solution with a lower concentration of solute and a higher concentration of water

Isotonic - solutions in which the concentrations of solute and water are equal

Water flows from hypotonic to hypertonic solutions until isotonic solutions are achieved.

Active Transport - cell expends energy to move molecules across a membrane from low to high concentration, ex. protein pumps

Exocytosis - taking materials outside a cell through the use of a vesicle

Endocytosis - the process of taking materials into a cell within vesicles that bud inward from the plasma membrane

Microscopes:

Base - used for support

Arm - supports the tube and connects it to the base

Body Tube - connects the eyepiece to the objective lenses

Ocular - the lens that you look through, which magnifies the image by 10x

Revolving Nosepiece - allows you to easily rotate and change objective lenses

Scanning Power Objective - magnifies the image 4x

Low Power Objective - magnifies the image 10x

High Power Objective - magnifies the image 40x

Stage - the flat platform where you place your slides

Stage Clips - holds the slides in place

Diaphragm - varies the light intensity that is projected upward into the slide

Coarse Adjustment - allows you to focus in on the specimen

Fine Adjustment - allows you to fine-tune the focus after you used the coarse adjustment

Light Source - illuminates the slide

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