Human Sensory Perception and Nervous System Fundamentals

Understanding Sensory Perception

Perceptions are created when information gathered by receptors is sent to the brain through the nerves.

The receptor’s function is to gather information from both the external and internal environments.

The Sense of Touch: Skin

The skin, our largest organ, contains numerous receptors for touch, temperature, and pain. It is composed of two primary layers:

  • Epidermis: The outer layer of the skin.
  • Dermis: The inner layer of the skin.

The Sense of Taste

Taste buds are specialized

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Microbiology Fundamentals: Growth, Metabolism, and Control

Microbiology Essentials: Core Concepts

Key Microbial Definitions

Binary Fission
A process where a cell elongates, chromosomes replicate, nuclear material divides, the membrane invaginates to the center, and the wall thickens and grows inward, resulting in two daughter cells.
CHONPS
Essential elements for life:
  • Carbon (synthesis of organic molecules)
  • Hydrogen (source of electrons)
  • Oxygen (electron acceptor, component of organic molecules)
  • Nitrogen (amino acids)
  • Phosphorus (phospholipids, nucleic acids)
  • Sulfur
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Genetic Inheritance: Principles, Laws, and Applications

Genetics is a branch of biology that studies the transmission of hereditary traits and genes. Genetic inheritance refers to the series of mechanisms that transmit traits from an individual to its descendants.

Genetic Inheritance: Core Concepts

Genes and Hereditary Traits

The following are some of the basic concepts of genetic inheritance:

  • Hereditary traits are the morphological or physiological characteristics of an individual that can be transmitted to their descendants, such as eye color.
  • A gene is
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Human Digestive System: Anatomy and Functions

Small Intestine Anatomy and Function

Intestinal Wall Structure

The thin wall of the small intestine is composed of several layers: the intestinal mucosa, muscular layer, and serous layer. The intestinal mucosa throughout the entire intestine has a simple columnar epithelium. It also contains defensive lymphoid tissue, called Peyer’s patches, which are abundant in the jejunum and ileum.

Mucosal Features for Absorption

To increase the absorption surface, the mucosa features:

  • Valvulae conniventes (or plicae
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Molecular Biology Essentials: DNA, RNA, and Gene Function

Fundamentals of Molecular Biology

RNA Nucleotide Components

An RNA nucleotide consists of three main parts:

  • A ribose molecule
  • A phosphate group
  • A nitrogenous base

The Central Dogma of Molecular Biology

Information is transferred from DNA to RNA to protein.

Gene Expression and Regulation

Impact of Promoter Sequence Mutations

A mutation in the promoter sequence of a gene might prevent RNA polymerase from binding. As a result, the gene would not be transcribed.

DNA Preparation for RNA Synthesis

Before RNA polymerase

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Ciclo de la Reproducción Humana y Desarrollo Sexual

La Reproducción Humana

Las personas nos reproducimos sexualmente: las hembras producen gametos femeninos llamados óvulos y los machos producen gametos masculinos llamados espermatozoides. Estas dos células se unen para formar el cigoto.

La fecundación es interna, es decir, el óvulo y el espermatozoide se unen en el tracto reproductivo interno femenino. El desarrollo del nuevo ser ocurre dentro del aparato reproductor femenino; somos vivíparos.

Procesos Clave de la Reproducción Humana

La reproducción

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