Cell Structures: Organelles, Bacteria, Viruses, and Fungi

Cell Structures and Components

Nuclear membrane: A double membrane that surrounds the nucleus of the cell. It contains small pores that allow communication between the nucleus and the cytoplasm.

Chromosomes: Immersed in the nuclear fluid, they become visible only when the cell begins to divide. Chromosomes are carriers of genes, the factors responsible for the transmission of hereditary traits. Their number varies across different cell types and species. Generally shaped like elongated filaments,

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Genetics: Key Concepts, DNA, and Genetic Disorders

Genetics: Key Concepts and Applications

The physical location of a gene on a chromosome is the locus.

Different versions of a given gene are called alleles.

A combination of alleles is known as a genotype.

The physical trait caused by a combination of alleles is known as a phenotype.

What is the sequence of nucleotides in the complementary strand of DNA that will match the following strand of DNA? ATGATAGCC? TACTATCGG

The presence of a widow’s peak is controlled by a dominant allele (P), while the absence

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Understanding Key Concepts in Bioenergetics and Metabolism

ATP Synthase: A membrane-embedded protein complex that regenerates ATP from ADP with energy from protons diffusing through it.

ATP: The cell’s energy currency.

Acetyl CoA: The combination of an acetyl group derived from pyruvic acid and coenzyme A, which is made from pantothenic acid (a B-group vitamin).

Activation Energy: The amount of initial energy necessary for reactions to occur.

Active Site: A specific region on the enzyme where the substrate binds.

Allosteric Inhibition: The mechanism for inhibiting

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Cell Membrane Structure and Function: A Comprehensive Review

Cell Membrane Structure: The Fluid Mosaic Model

Singer and Nicholson proposed the fluid mosaic model in 1972.

Under an electron microscope, the plasma membrane appears as two dark bands separated by a clear layer.

  • The membrane is not rigid but fluid.
  • The membrane is a fluid mosaic where the lipid bilayer cements the network. Proteins are embedded within or interact with each other. Both lipids are amphipathic substances.
  • Both proteins and lipids can move laterally.
  • Lipids and integral proteins are arranged
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Microsurgery, Antimicrobial Therapy, and Laser Principles

Microsurgery Defined

Microsurgery is defined as a refinement in operative technique by which visual acuity is enhanced with the surgical operating microscope.

Microsurgery vs. Macrosurgery

The difference between microsurgery and macrosurgery is: In macrosurgery, hand movements are guided proprioceptively, whereas in microsurgery, they are guided visually.

Microsurgery: Advantages and Disadvantages

Advantages

  • Less tissue trauma
  • Less morbidity
  • Less patient anxiety
  • Atraumatic tissue manipulation
  • Accurate primary
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Understanding Pulmonary Function: Tests and Regulation

Pulmonary Function

The breathing mechanism aims to provide an uninterrupted flow of oxygen from the environment to cells.

To carry out this function, the lungs, blood, and mitochondria work together.

The lung is the gas exchange organ, the blood carries oxygen to tissues, and mitochondria enable its use.

The speed and depth of breathing are controlled by involuntary processes in the brainstem.

In each inhalation and exhalation, more than half a liter of air is exchanged.

Respiratory function can be divided

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