Non-Infectious Diseases: Types, Causes, and Prevention
Non-Infectious Diseases
(Which are not communicable or contagious)
Cardiovascular Diseases
Affecting the heart and blood vessels.
- Atherosclerosis: Thickening of the artery walls due to the deposition of cholesterol, platelets, and the formation of fibrous tissue. Favors thrombus formation (blood clot that occurs in an artery or vein and leads to an obstruction that can lead to a stroke).
- Aneurysm: Narrowing of the artery wall; the artery can rupture and cause bleeding.
- Strokes: Interruption of blood supply
Cellular Structures and Active Transport Mechanisms
Active Transport
In this type of transport, substances span the membrane against the concentration gradient. Molecules bind to transport proteins and move against the gradient through the input of energy, often in the form of ATP, from the cell.
Cell Wall
Not all living things have cell walls; they are present only in eukaryotic plant cells. They form channels within the plant called plasmodesmodes. The cell wall is constituted by a middle layer (the outermost layer), which is thin and flexible, and
Read MoreCell Structure and Function
The Cell: Structure and Vital Functions
The cell is composed of three main elements: the membrane, cytoplasm, and genetic material. It performs three vital functions: nutrition, relationships, and reproduction.
The Plasma Membrane: Cell Boundary and Exchange
The plasma membrane acts as a boundary, limiting the cell’s contents while allowing the exchange of matter and energy with the surrounding environment. It consists of lipids, proteins, and carbohydrates. The plasma membrane has a fluid mosaic structure,
Read MoreRNA Synthesis: Transcription Process in Detail
The Synthesis of RNA (Transcription)
The synthesis of RNA, or transcription, occurs in the nucleus and requires:
- A DNA strand serving as a template: Of the two chains of nucleotides that make up the gene, only one, the template, is actually transcribed, while the other, called the coding strand, is not.
- Enzymes: The process is catalyzed by RNA polymerases. In prokaryotes, only one exists, whereas in eukaryotes there are three: RNA polymerase I, II, and III. RNA polymerase I is involved in the formation
Endocrine and Nervous Systems: Functions and Hormones
Endocrine and Nervous Systems
Nervous System: Fast action and very short duration. Effect is localized and fleeting.
Endocrine System: Action is slow but long-lasting. Effect is widespread, medium and long term.
Major Glands
Pituitary, Thyroid, Parathyroid, Adrenal, Pancreas, and Ovary/Testicle.
Hormones
A hormone is any chemical secreted in body fluids by a cell or a group of cells that has a control function. It is secreted and acts at a specific location.
Local Hormones
Produced in the system itself
Read MoreDigestive and Urinary Systems: Key Functions
Digestive System Functions and Processes
- Which of the following is not a function of the digestive system?
Filtration - The activities of the digestive system are regulated by:
All of the above - Sandwiched between the layer of the circular and longitudinal muscle in the muscularis externa is the:
Myenteric Plexus - Functions of the large intestine include:
All of the above - Digestion refers to the:
B and C only - Functions of the stomach include all the following, except for:
Absorption of triglycerides - Which