x
Search
Exact matches only
Search in title
Search in content
Search in excerpt
Search in comments
Filter by Custom Post Type

Epithelial Tissues – Simple And Stratified: Functions, Locations And Difference

By | 2018-07-11T05:58:50+00:00 July 24th, 2017|General, Physiology|

Epithelial tissues, or epithelia (singular, epithelium), may be composed of one or more layers of cells. The number of cell layers and the shape of the cells provide the basis for classifying epithelial tissues. Epithelial tissues are distinguished by the following five characteristics: Epithelial cells are packed closely together with very little extracellular material between [...]

Simple & Facilitated Diffusion, Osmosis – Across Plasma Membranes

By | 2018-07-11T05:59:39+00:00 July 24th, 2017|General, Physiology|

A cell keeps its homeostasis mainly by managing the movement of substances across the selectively permeable plasma membrane. Some substances pass across the plasma membrane by passive transport, which needs no expense of ATP by the cell. Other substances move across the plasma membrane by active transport, which needs the cell to use up ATP. [...]

Difference Between DNA And RNA

By | 2018-07-11T05:59:48+00:00 July 24th, 2017|General, Physiology|

Feature DNA RNA Sugar Types of nitrogenous bases Variety of nitrogenous bases Variety of nucleotide chains Site of action Function Deoxyribose A, T, C, G Balances 108 base sets 2 (double helix) Functions in nucleus; can not leave Codes for synthesis of RNA and protein Ribose A, U, C, G 70-10,000 bases, primarily unpaired One Leaves [...]

Action Potential

By | 2018-07-11T05:59:56+00:00 July 24th, 2017|General, Physiology|

Action potentials are the principal mechanism of nerve impulse propagation and transmission, and they allow depolarization at a single region of skeletal and cardiac muscle cells to spread across the entire cell.Action potentials require a stimulus that depolarizes the cell membrane potential to a threshold value, and then a sufficient density of voltage-gated channels to [...]

Passive Transport – Simple and Facilitated Diffusion and Osmosis

By | 2018-07-11T06:00:17+00:00 July 24th, 2017|General, Physiology|

Passive transport describes the mechanism of transport of substances along the gradient without expense of any energy It relies on the physical aspects like concentration gradient, electrical gradient and pressure gradient. Given that the transport of substances takes place along the gradient, this process is likewise called down-hill movement The passive transport mechanisms operating at [...]

Gene Regulation

By | 2018-07-11T06:00:30+00:00 July 24th, 2017|General, Physiology|

Genes do not just produce their products at a constant, relentless speed, like a 24- hour continuously manufacturing plant. They are switched on and off from day to day, even hour to hour, as their products are required or not, and lots of genes are completely shut off in any provided cell. The genes for [...]

Signal Transduction – Membrane And Lipid-Soluble

By | 2018-07-11T06:00:39+00:00 July 24th, 2017|General, Physiology|

Membrane Receptor Signal Transduction Proteins, peptides, and charged molecules do not easily diffuse across the cell membrane. Consequently, the cell membrane can serve as a barrier to cell-to-cell communication when such agents are used as neurotransmitters and hormones. This communication barrier is overcome by use of proteins embedded in the cell membrane that function as [...]

Active Transport – Primary and Secondary Processes

By | 2018-07-11T06:00:50+00:00 July 24th, 2017|General, Physiology|

Active transport describes the mechanism of transport of substances versus the chemical and/or electrical gradient. Active transport includes expense of energy which is freed by breakdown of high energy substances like adenosine triphosphate (ATP). Considering that the transport of substances happen versus the chemico-electrical gradient, this process is likewise called up-hill movement Substances carried actively [...]

Protein Synthesis Process and Role of DNA And RNA In It

By | 2018-07-11T06:01:41+00:00 July 24th, 2017|General, Physiology|

Proteins play an important role in the body. Structural proteins make up substantial parts of all cells, and practical proteins, such as enzymes and hormones, straight manage cellular activities. Bear in mind that a protein is formed of a long chain of amino acids collaborated by peptide bonds. Protein synthesis includes positioning a particular amino [...]

Cell-To-Cell Communication

By | 2018-07-11T06:01:48+00:00 July 24th, 2017|General, Physiology|

Normally the cell membrane isolates a cell from the adjacent tissue. As a consequence, any cell-to-cell message must first transit the cell membrane. One exception to that arrangement is a feature found in cardiac and smooth muscle cells: the gap junction. A gap junction is a direct pathway that joins the cytoplasm of adjacent cells [...]