Clinical Pathology II

UNIT 1: INTRO TO PATHOLOGY

Pathology

Pathology involves the prevention, diagnosis, and treatment of disease and examines abnormal changes in tissues, cells, body fluids and other substances in the body.

Differentiate between symptoms and signs

Symptoms are what the patient feels, and signs are abnormalities that can be detected by physical or laboratory examination.

Differentiate between aetiology and pathogenesis

Aetiology is the cause of a disease, whereas pathogenesis is the mechanism by which the cause produces the disease.

Prognosis

This refers to how the patient is expected to do, including whether and how well they are likely to recover.

Differentiate catabolism and anabolism

Catabolism breaks down organic matter to produce energy, whereas anabolism uses energy to construct complex such as proteins and nucleic acids

Functions of the nucleus

The nucleus contains the genome and is the main site of DNA and RNA synthesis. It is surrounded by a double nuclear membrane.

Functions of the mitochondria

Mitochondria generates energy, which provides energy for cellular reactions

Functions of ribosomes

Ribosomes translate RNA sequences and synthesise proteins

Differentiate rough ER and smooth ER

Rough ER has ribosomes attached to its outer surface and is associated with protein production, folding and glycosylation. Smooth ER lacks attached ribosomes and is involved in lipid biosynthesis.

What molecule is generated by mitochondria to provide energy for cellular reactions?

ATP (Adenosine Triphosphate)

What is the function of Golgi apparatus?

It processes and packages cellular products for transport within and out of the cell

What is the function of a lysosome?

Contain digestive enzymes that break down cellular material

What is the pathway of a protein destined for secretion?

Ribosome - Rough ER - Golgi apparatus - Secretory vesicle - Cell membrane

What is the basic structure of a cell membrane?

A phospholipid bilayer with hydrophilic heads facing the aqueous environments and hydrophobic tails facing inward.

What is the difference between passive diffusion and facilitated diffusion?

Both move substances down the concentration gradient without energy. Passive diffusion occurs directly through the membrane, while facilitated diffusion uses membrane proteins.

How does the facilitated diffusion differ from passive diffusion?

Facilitated diffusion moves substances from high to low concentration through membrane proteins, without requiring cellular energy.

How can cells receive signals across the cell membrane?

Lipid-soluble molecules can cross the membrane, while the other signalling molecules bind to membrane receptors and trigger an internal signalling cascade.

What are the functions of the cytoskeleton?

It provides shape and structure and is involved in intracellular transport, cell division, and cell movement.

What are the three main types of cytoskeletal filaments?

Microfilaments, microtubules, and intermediate filaments

What is a tissue?

A group of cells with similar shape and functions.

What are the four types of tissue?

Epithelial, Connective, Muscle, and Nervous

What are the three types of muscle tissue?

Smooth, striated, and cardiac

What are stem cells?

Progenitor cells that can differentiate into different cell types within the body.

What are labile tissues?

They contain mature cells that are capable of continuous division and regeneration throughout life.

What are stable tissues?

Do not continuously divide, but retain the ability to regenerate when needed. E.g., kidney, liver

What are permanent tissues?

They are considered unable to divide, therefore damage to these tissues can be serious because their ability to regenerate is very limited. E.g., neurone, cardiac tissue

What is apoptosis?

A controlled/programmed form of cell death in which unwanted or damaged cells are removed without spilling cellular contents and generally without causing inflammation.

What is the difference between apoptosis and necrosis?

Apoptosis is a controlled/programmed form of cell death that generally does not cause inflammation, whereas necrosis is an accidental/premature form of cell death that releases cellular components and triggers inflammation.

What are the 2 pathways of apoptosis?

Extrinsic and intrinsic pathways

Give three causes of necrosis?

Ishaemia, infection, and drugs

Why does apoptosis generally not cause inflammation?

Apoptotic bodies are rapidly phagocytosed without spilling their cellular contents into surrounding tissue, so an inflammatory response is generally not triggered.

What type of necrosis causes harm to heart tissues?

Coagulative necrosis