CELL PHYSIOLOGY

Cell physiology (including cellular electrophysiology) is the biological study of the cell's mechanism and interaction in its environment. The term "physiology" refers to all the normal functions that take place in a living organism. Absorption of water by roots, production of food in the leaves, and growth of shoots towards light are examples of plant physiology.  The heterotrophic metabolism of food derived from plants and animals and the use of movement to obtain nutrients (even if the organism itself remains in a relatively stationary position) are characteristic of animal physiology. These are the parts of cell and their functions.

CELL MEMBRANE OR PLASMA MEMBRANE

The cell membrane encloses every human cell

Structure - 2 primary building blocks include protein (about 60% of the membrane) and lipid, or fat (about 40% of the membrane). The primary lipid is called phospholipid, and molecules of phospholipid form a 'phospholipid bilayer' (two layers of phospholipid molecules). This bilayer forms because the two 'ends' of phospholipid molecules have very different characteristics: one end is polar (or hydrophilic) and one tails is non-polar (or hydrophobic).  Functions include:

 supporting and retaining the cytoplasm

 being a selective barrier

  transport

CYTOPLASM

Cytoplasm consists of a gelatinous solution and contains microtubules (which serve as a cell's cytoskeleton) and organelles (literally 'little organs')

CYTOSKELETON

The cytoskeleton represents the cell's skeleton. Like the bony skeletons that give us stability, the cytoskeleton gives our cells shape, strength, and the ability to move, but it does much more than that. The cytoskeleton is made up of three types of fibers that constantly shrink and grow to meet the needs of the cell: microtubules, microfilaments, and actin filaments. Each type of fiber looks, feels, and functions differently.

MICROTUBULES

Microtubules consists of a strong protein called tubulin and they are the 'heavy lifters' of the cytoskeleton. They do the tough physical labor of separating duplicate chromosomes when cells copy themselves and serve as sturdy railway tracks on which countless molecules and materials shuttle to and fro. They also hold the ER and Golgi neatly in stacks and form the main component of flagella and cilia.

MICROFILAMENTS

Microfilaments are unusual because they vary greatly according to their location and function in the body. For example, some microfilaments form tough coverings, such as in nails, hair, and the
outer layer of skin (not to mention animal claws and scales). Others are found in nerve cells, muscle cells, the heart, and internal organs. In each of these tissues, the filaments are made of different proteins.

Actin filament are made up of two chains of the protein actin twisted together. Although actin filaments are the most brittle of the cytoskeletal fibers, they are also the most versatile in terms of
the shapes they can take. They can gather together into bundles, weblike networks, or even three-dimensional gels. They shorten or lengthen to allow cells to move and change shape. Together with a protein partner called myosin, actin filaments make possible the muscle contractions necessary for everything from your action on a sports field to the automatic beating of your heart.

NUCLEUS

Cells also contain a nucleus within which is found DNA (deoxyribonucleic acid) in the form of chromatin (or chromosomes during cell division) plus nucleoli (within which ribosomes are formed)

nuclear membrane - the membrane that surrounds the nucleus

nucleolus - an organelle within the nucleus - it is where ribosomal RNA is produced

ENDOPLASMIC RETICULUM

Endoplasmic reticulum comes in 2 forms: smooth and rough; the surface of rough ER is coated with ribosomes; the surface of smooth ER is not coated with ribosomes functions include: mechanical support, synthesis (especially proteins by rough ER), and transport. The endoplasmic reticulum (ER) is a special membrane structure found only in eukaryotic cells. Some ER has ribosomes on the surface (rough endoplasmic reticulum) --the cell's protein-making machinery. Proteins that require special conditions or are destined to become part of the cell membrane are processed in the ER and then handed off to another organelle called the Golgi apparatus.

GOLGI BODIES consists of a series of flattened sacs (or cisternae)
Functions include: synthesis (of substances likes phospholipids), packaging of materials for transport (in vesicles), and production of lysosomes. The Golgi functions as a cellular post office. Proteins that arrive there are sorted, packaged and transported to various destinations in the cell. Scientists are studying many aspects of the ER and Golgi apparatus, including a built-in quality control mechanism cells use to ensure that proteins are properly made before leaving the ER

LYSOSOMES

It is a membrane-enclosed spheres that contain powerful digestive enzymes functions include destruction of damaged cells (which is why they are sometimes called 'suicide bags') & digestion of phagocytosed materials

MITOCHONDRIA

It have a double-membrane: outer membrane & highly convoluted inner membrane inner membrane has folds or shelf-like structures called cristae that contain elementary particles; these
particles represent an enzyme important in ATP production primary function is production of adenosine triphosphate (ATP) Mitochondria are found exclusively in eukaryotic cells. These organelles are often called the "power plants" of the  cell because their main job is to make energy (ATP). Mitochondria are highly unusual--they contain their own genetic material and protein-making machinery enwrapped in a double membrane. Many scientists believe mitochondria were once free-living bacteria that colonized complex cells sometime during evolution.

RIBOSOMES  Ribosomes composed of rRNA (ribosomal RNA) & protein may be dispersed randomly throughout the cytoplasm or attached to surface of rough endoplasmic reticulum often linked together in chains called polyribosomes or polysomes primary function is to produce proteins

CENTRIOLES  It is a paired cylindrical structures located near the nucleus, it also plays an important role in cell division.

Flagella & cilia - hair-like projections from some human cells.  Cilia are relatively short & numerous (e.g., those lining trachea). A flagellum is relatively long and there's typically just one (e.g., sperm)

Villi - projections of cell membrane that serve to increase surface area of a cell (which is important, for
example, for cells that line the intestine)

Cell wall - a thick, rigid membrane that surrounds a plant cell. This layer of cellulose fiber gives the cell most of its support and structure. The cell wall also bonds with other cellwalls to form the structure of the plant.

Stroma - part of the chloroplasts in plant cells, located within the inner membrane of chloroplasts, between the grana.
Thylakoid disk - thylakoid disks are disk-shaped membrane structures in chloroplasts that contain chlorophyll. Chloroplasts are made up of stacks of thylakoid disks; a stack of thylakoid disks is called a granum. Photosynthesis (the production of ATP molecules from sunlight) takes place on thylakoid disks.

Amyloplast - an organelle in some plant cells that stores starch. Amyloplasts are found in starchy plants like tubers and fruits.

Chlorophyll - chlorophyll is a molecule that can use light energy from sunlight to turn water and carbon dioxide gas into sugar and oxygen (this process is called photosynthesis). Chlorophyll is magnesium based and is usually green.
Chloroplast - an elongated or disc-shaped organelle containing chlorophyll. Photosynthesis (in which energy from sunlight is converted into chemical energy - food) takes place in the chloroplasts. 
Granum - (plural grana) A stack of thylakoid disks within the chloroplast is called a granum.