Notes, summaries, assignments, exams, and exercises for Biology for Baccalaureate

Chromoproteins and Respiratory Pigments

Certain molecules also belong to the chromoproteins group.

Hemocyanin

Hemocyanin is very similar to hemoglobin and shares the same function as a gas carrier. The metal present in its prosthetic group is copper. It appears blue when combined with O2 and colorless when reduced. It is primarily found in invertebrates.

Chlorophyll

Chlorophyll is a photosynthetic pigment characterized by containing a magnesium (Mg) atom. It is specialized to capture photons and releases electrons when light rays impinge upon it.

Holoproteins: Simple Proteins

Holoproteins are simple proteins formed exclusively by amino acids. They serve various biological functions:

• Albumins: These lack glycine. Examples include ovalbumin (egg), lactalbumin

The Big Bang Theory

Matter, energy, and space were once concentrated in a primeval atom, where density and temperature were extremely high. This atom expanded in a massive explosion known as the Big Bang. As the universe expanded, matter, space, and time originated. Subatomic particles were generated, leading to the formation of the simplest atoms: hydrogen and helium. As the temperature of the universe decreased, condensed particles formed planets, galaxies, and stars.

Cell Theory

The cell theory is defined by the following principles:

• Structural Unit: All living things are made of cells or their secretions. The cell is the structural unit of living matter.
• Origin: All cells come from preexisting cells through division. It is the unit of origin

Endangered Species and Conservation Categories

According to the International Union for Conservation of Nature (IUCN), a species is considered endangered when it is in danger of disappearing if the factors threatening its continuity persist, or if it has suffered a drastic decline in its population or habitat.

While the tropics are the most threatened regions, this phenomenon is spreading worldwide. In Spain, the National Catalogue of Endangered Species establishes four categories for inclusion:

• In danger of extinction: When negative factors make survival unlikely in the short term. Examples include the monk seal, the holly, and the giant lizard of El Hierro.
• Sensitive to habitat alteration: When there is a medium-term risk of extinction in the

Disease Classification and Types

Specific Disease Categories

3. Diseases of Specific Organ Systems

   These affect different organs and body systems, including diseases of the respiratory, circulatory, and peripheral systems.

4. Autoimmune Diseases

   Autoimmune diseases are caused by a failure of the immune system, resulting in the production of molecules that harm the organism.

5. Diseases Caused by Accidents

   This category includes diseases resulting from traffic accidents, domestic incidents, work-related injuries, etc.

Infectious Diseases: Definitions and Dynamics

Prevalence vs. Incidence

Prevalence is defined as the total number of patients with a disease at a given time, while incidence refers to the new cases of disease appearing in populations over a specific...

The Cardiac Cycle

The cardiac cycle is the period between one cardiac contraction and the next. It is divided into three stages:

• Atrial systole: Lasts 0.1 seconds. It produces contraction of the atria. Blood passes through the mitral and tricuspid valves into the ventricles. Meanwhile, the semilunar valves are closed, preventing blood from leaving the ventricles.
• Ventricular systole: Lasts 0.3 seconds. Once blood reaches the ventricles, they contract; the mitral and tricuspid valves close to prevent backflow into the atria. Semilunar valves open, allowing blood to leave the ventricles. This opening is passive due to increased intraventricular pressure, and the outflow of blood is intermittent, perceived as the arterial pulse.
• General diastole:

Fundamentals of Cell Biology

A cell (from the Latin cellula, a diminutive of cellam, meaning small room) is the morphological and functional unit of all living organisms. In fact, the cell is the smallest element that can be considered alive. Living organisms can be classified according to the number of cells they possess:

• Unicellular: Organisms with only one cell, such as protozoa or bacteria.
• Multicellular: Organisms with multiple cells, ranging from a few hundred in some nematodes to hundreds of billions in human beings.

Biological Tissues and Histology

In biology, tissues are materials consisting of an organized group of cells and their organelles, differentiated in a particular way and arranged regularly. They exhibit coordinated physiological...

Cephalic Tract

The mouth can be a simple opening or have structures that allow for the active capturing of food and the start of chemical and mechanical digestion. Some modifications of the mouth include:

• Mouthparts: Characteristics of arthropods. These pieces are organized around the mouth and differ depending on the food source.
• Beaks: Horny structures consisting of two parts designed to capture and tear food.
• Teeth: In addition to retaining prey, they start the mechanical digestion of food. They are responsible for cutting, tearing, and chewing. These are present in mammals.
• Chelicerae: Nail-like parts found in spiders; they also contain venom used to paralyze prey.

A pouring of mouth secretions comes from the salivary glands. Saliva secretion...

Core Principles of Biological Classification

Taxonomy

Taxonomy is a subdiscipline of systematic biology that studies the relationships among organisms and their evolutionary history. Today, taxonomy aims to resolve the phylogenetic tree of the organisms studied. This means organizing them into clades, or evolutionary branches, based on their relationships.

Systematics

Systematics is the study of the classification of species according to their evolutionary history (phylogeny).

The Hierarchical System of Taxonomy

Taxon

A taxon is a group of related organisms that, in a given classification, have been grouped together. The group is given a Latin name, a description, and a "type." For a species, the type is a specific, exemplary specimen.

Taxonomic Category

Taxa,...

Fundamental Biological Concepts

Energy Acquisition and Matter Cycling

Autotrophic Organisms

They produce organic matter from inorganic matter (mineral salts, water, etc.) using solar energy.

Heterotrophic Organisms

These are organisms that feed on organic material previously produced by autotrophic organisms.

Photosynthesis

This is the process by which plants, algae, and some bacteria use light energy to synthesize organic matter from carbon dioxide and water.

Cellular Respiration

This is the process in which the organic matter synthesized in photosynthesis is broken down to produce necessary energy for the organism.

The Earth and Life's Domain

Biosphere

The surface area of Earth where living matter exists.

Origins of Life and Planetary Components

Where

Immune Memory and Lymphocyte Response

The formation of memory cells of all types of lymphocytes involved in the immune response after initial contact with an antigen (primary immune response) allows the immune response to be much faster during a second contact, even several years after the first (secondary reaction). This can be verified by measuring the dose of antibodies in an organism in both situations.

• Primary immune reaction: Production of antibodies in the IgM form.
• Secondary immune reaction: Faster and wider production of antibodies in the IgG form.

Types of Immunity

Immunity is the protection against infectious agents. An organism is considered immune to an antigen when it is able to destroy or deactivate it without suffering from any disease....