Notes, summaries, assignments, exams, and exercises for Biology for Secondary education

Pulmonary Ventilation

Pulmonary ventilation is the process by which atmospheric air enters the interior of the lungs and then leaves them to the atmosphere.

The movements in and out of the air that occur in pulmonary ventilation are caused by the volume changes experienced by the lungs, mainly due to the action of two types of muscles:

• Diaphragm. It is a muscle that lies below the lungs and separates the chest from the abdomen. By moving up or down it changes the capacity of the rib cage, which houses the lungs, and this produces the breathing movements.
• Intercostal muscles. These are the muscles between the ribs. By contracting and relaxing, they move the ribs and vary the volume of the lungs.

Inspiration and Expiration

Pulmonary ventilation is...

Organs, Systems, and Apparatuses

Organs are structures composed of various tissues associated with performing a specific function. Organs are part of the apparatuses and systems that, in turn, constitute the human body.

Understanding Organs and Organography

Organography is the science that studies the structure and morphology of organs, while physiology is the science that studies their functions.

Major Systems of the Human Body

Systems consist of organs of the same type that perform similar functions.

• Muscular System

  This is the active part of the locomotor system. It consists of skeletal muscles composed of striated muscle tissue. It is responsible for locomotion, facial expressions, and the maintenance of posture.

• Skeletal System

  This is the passive

Fundamental Ecological Laws

Liebig's Law of the Minimum

Established in 1840, this law states that plant development depends on the minimum quantity of a specific element present (e.g., water, gas).

Shelford's Law of Tolerance

This principle dictates that the existence and prosperity of an organism depend on the deficiency or excess of factors approaching its tolerance limits. Organisms vary in their ability to tolerate environmental conditions.

• Stheno: Organisms with narrow tolerance ranges.
• Eury: Plants and animals with wide tolerance ranges.

Biotic Interactions

Biotic factors include diseases, predation, and parasitism.

Types of Relationships

• Interspecific Relationships: Interactions between different populations.
• Intraspecific Relationships: Interactions

Circulatory System: Blood and Lymph

The circulatory system is responsible for distributing food (nutrients) and oxygen throughout the body. Blood, lymph — HCH-HCH.

Circulatory Blood

Circulatory blood (a tissue of cells suspended in a liquid medium) includes several components:

Plasma

Plasma: acellular liquid (about 90% water) containing dissolved substances, including:

• Nutrients: glucose, amino acids, lipids, water and minerals — transported from the digestive tract to the rest of the body;
• Waste products: transported from cells to the excretory organs (e.g., urea), excess salts and carbon dioxide;
• Hormones: carried from producing glands to the organs where they are used;
• Other substances dissolved in plasma.

Red Blood Cells / Erythrocytes

Red blood

Core Concepts in Ecology

Defining Ecological Units

• Population: A group of organisms of the same species within a defined area that coexist.
• Biotope: The physical environment or place occupied by a community, characterized by environmental conditions such as light or humidity.
• Ecosystem: A community (including different populations) and the biotope in which it is found, where they relate to each other and the physical environment (MDI).
• Environment (MDI): The surroundings of an organism or species, made up of all the factors or conditions that exist in the place where it lives and influence it.

Environmental Factors

Environmental factors include:

• Biotic Factors: Interactions between living organisms, such as the struggle for food or space, or mutual

1. Levels of Organization

Degrees of complexity are called organizational levels. Abiotic levels can be differentiated from biotic levels.

• N. Subatomic: Formed by elementary particles (quarks, leptons, etc.).
• N. Atomic: Atoms.
• N. Molecular: Molecules made up of grouped atoms. The molecules of living things begin here (organic and inorganic).
• N. Cellular: Where we find the cell.
• N. Tissue: A set of specialized cells with the same function and origin.
• N. Organ: Different tissues grouped to form one function.
• N. System: Organs that function together to form one apparatus.
• N. Apparatus: Set of organs with different functions involved in one or more of them.
• N. Organism: The living being as a whole.

2. Variety of Atomic Functional Units and Cells

All living...

Cellular Components and Organelles

• Ribosomes and membrane-bound organelles: Each is devoted to a specific function. The nucleus, composed of genetic material surrounded by a membrane, is a specialized organelle.
• Cytoskeleton: A network of filaments and microtubules designed to maintain cellular shape and facilitate cell movement.

The Respiratory System

Parts of the Respiratory System

Airway

• Nostrils: Two cavities open to the outside and covered by nasal mucosa. They communicate with the pharynx through the choanae (posterior nares).
• Pharynx: The common duct for the respiratory and digestive tracts. It contains the epiglottis, which is located above the larynx and closes during swallowing to prevent choking.
• Trachea: A tube reinforced by elastic cartilaginous rings. In the thorax, it branches to form the bronchial tree.
• Bronchial Tree: Consists of two bronchi that enter the lungs and branch into smaller bronchioles. The walls contain mucus and cilia that beat toward the pharynx.
• Lungs: Located in the thoracic cavity, protected by the ribs and wrapped in two membranes called

The Human Heart: Structure and Function

The heart is a muscular organ approximately the size of a fist, situated in the center of the chest, between the two lungs.

Primary Function

Its main function is to pump blood through the blood vessels.

External and Internal Structure

Externally, it is formed by a muscle that contracts involuntarily. Internally, it consists of two halves separated by a partition. Each half is comprised of two chambers (atria at the top and ventricles at the bottom).

The Cardiac Cycle

The heart operates through two alternating movements: contraction (systole) and dilation (diastole). Each complete cycle consists of four distinct stages:

1. Diastole (Filling Phase)

• Blood from different parts of the body enters the atria, causing

another part of the nutrient most used by the glucose for fuel cells is made in these phenomena: consumption of oxygen necessary for prensencia phenomenon occurs libration of energy, used by the cells production of carbon dioxide and water, water for the body but the dioxide is a residue k must be cast.

useful energy for the body: there are three forms of energy: mechanical, for muscle contraction. Cause the movement of the skeleton of the heart beat. Quimica, to make new molecules. Thermal, maintains our body temperature between 35 and 37

respiratory system is responsible for circulating the air between the body and the external environment there are two ways the upper Respiratory: is the nose and pharynx are the laringelas imferiores trachea...