Nutrition Basics

Nutrition involves how our bodies obtain, process, and utilize essential nutrients from food. These nutrients, vital for cell function and survival, include:

Types of Nutrients

• Carbohydrates: The primary energy source. Glucose provides quick energy, while complex carbohydrates (starch, glycogen) require longer digestion. Cellulose, a plant fiber, aids digestion.
• Lipids (Fats): Store energy and form reserves in adipose tissue. Phospholipids are crucial components of cell membranes.
• Proteins: Essential for cell structure and regulatory functions.
• Water: The most abundant component, vital for cooling, transporting substances, waste elimination, and facilitating chemical reactions.
• Minerals: Play structural and regulatory roles in various

Polymers are complex structures composed of repeating molecular units called a monomer.

Carbohydrates: Structure and Function

Functions of Carbohydrates

• Energy: Delivered or stored energy.
• Structural: Form structures (e.g., insect shells).

Classification by Monomer Count

1. Monosaccharides: Single monomer unit.
2. Disaccharides: Two monomer units.
3. Trisaccharides: Three monomer units.
4. Oligosaccharides: From 4 to 10 units.
5. Polysaccharides: 11 to hundreds of thousands of units.

Classification by Monomer Carbon Atoms

• Trioses: 3 carbon atoms.
• Tetroses: 4 carbon atoms.
• Pentoses: 5 carbon atoms.
• Hexoses: 6 carbon atoms.

Glucose Cyclization

The Glucose Cyclic structure is formed when oxygen, which is negatively charged and nucleophilic, joins the carbon atom at the end of...

Anatomy and Function of the Human Heart

The heart is located in the anterior mediastinum to the left of the midline of the body and weighs between 250 and 300 grams. It forms a cone shape, with its apex (lower corner) pointing downward, to the left, and forward. It has three faces: anterior, inferior, and posterior.

The Three Layers of the Heart

• External (Pericardium): Consists of two layers (leaves) with serous pericardial fluid between them that reduces friction.
• Middle (Myocardium): The heart muscle itself, composed of striated muscle in involuntary bundles.
• Internal (Endocardium): The inner lining of the chambers and heart valves.

The Heart Conduction System

The electrical conduction system of the heart consists of:

• Sinoatrial (SA) node (the natural

Circulatory System Components and Structure

Veins and Arteries Function

Veins empty into the atria. They have thin and rigid walls. Valves prevent reverse blood flow. Veins carry blood from tissues to the heart.

Arteries: These originate from the ventricles. The major arteries are elastic and contain significant muscle tissue. They lack valves and carry blood to the tissues.

Heart Location and Boundaries

The heart is located in the thoracic cavity within the mediastinum. It has the following boundaries:

• Anteriorly: Chest muscles, sternum, and ribs.
• Posteriorly: Ribs, muscles, spine, and lungs.
• Inferiorly: Below the diaphragm.
• Superiorly: Over veins and arteries.
• Laterally: Ribs, intercostal muscles, and lungs.

Heart Wall Layers

The heart has three main...

Immediate Nutritional Principles

Macronutrients and Essential Components

Carbohydrates

Fundamental energetic substances found in food mixtures. They are divided into two groups:

• Simple Carbohydrates (Sugars): Sweet, crystalline, and soluble in water.
• Complex Carbohydrates: Not sweet or crystalline. They are large molecules formed by the union of simple carbohydrate molecules.

Lipids (Fats)

Lipids are insoluble in water and have an oily appearance. They differ as follows:

• Fats: Highly energetic molecules based on their chemical composition:
  • Saturated Fats (typically animal origin).
  • Unsaturated Fats (typically vegetable origin).
• Lipid components of cell membranes.
• Lipids with regulatory functions.

Proteins

Structural molecules formed by the union of simpler...

Essential Biological Molecules

Carbohydrates and Energy

Carbohydrates are our greatest source of energy. Some have structural functions and backup functions; carbohydrates are also called hydrates of carbon.

Lipids and Functional Roles

Lipids are substances with a unique chemical composition. These substances perform multiple functions, both energetic and functional.

Proteins and Amino Acids

Proteins are made up of amino acids; there are 20 types that combine to form proteins. Proteins perform many functions in our body, such as:

• Structural function
• Hormonal regulation (regulating blood sugar levels)
• Transport (carrying O2 in the blood)
• Defense
• Contractile proteins
• Enzymes: Involved in all chemical reactions in the body.

Nucleic Acids: DNA and RNA

Nucleic

Bryophytes

Bryophytes are found in terrestrial environments with humidity, although some present adaptations that allow them to occupy a greater variety of environments, both by resisting immersion in totally aquatic environments and by surviving dehydration, acting as primary colonizers of, for example, rocks or bare soil, and even in regions of polar freezing. They remain, however, dependent on water, at least for the displacement of the flagellated anterozoid to the oosphere. This division has no representatives in marine environments.
They are eukaryotic, multicellular organisms, except for their reproductive cells, which are unicellular.

Bryophytes are found in terrestrial environments with humidity, although some present adaptations that...

The Digestive System: Organs and Processes

The main organs and processes of the digestive system are:

• Ingestion: the intake of food to be digested.
• Digestion: the transformation of food into nutrients, through mechanical and chemical processes.
• Absorption: the passage of nutrients from the intestine into the circulation.
• Egestion: the elimination of undigested substances.

The digestive system consists of 2 main components:

1. The digestive tube

The digestive tube is approximately 10 to 12 m long and has 2 openings: the entry (mouth) and the exit (anus).

• Mouth: contains the teeth, the salivary glands and the tongue.
• Pharynx: a short tube that is the common passage for air and food.
• Esophagus: a conduit that connects the pharynx to the stomach.
• Cardia: a

1. What organs derived from ectoderm?
Epidermis, hair, sebaceous glands and sweat glands, part of the nasal cavity, oral and anal, and nervous system.
2. What bodies originate from the mesoderm?
The connective tissues, adipose, cartilaginous, elastic, bone, muscles, circulatory system, part of the dermis, excretory system, peritoneum and most of the reproductive system.
3. What organs are derived from the endoderm?
The digestive tract (except mouth and anal canal) larynx, middle ear, liver, pancreas, coatings of para respiratory, bladder.
4. How is formed bone tissue?
By bone cells and bone ground substance.
5. How are they different bone cells: osteoblasts, osteocytes and osteoclasts?
Osteoblasts: bone cells of young man.
Osteocytes: osteoblasts...

Characteristics of Living Things

0-Nutrition:

The ability of a living being to attract foreign material and use it to their advantage to grow in size and develop, or simply to maintain their structures and perform other vital functions.

0-Relationship:

Is the ability to attract external stimuli and to give adequate responses to them. Without this function, living beings could not perform other vital functions such as reproduction.

0-Reproduction:

The ability to originate new individuals, the same or very similar to the parents.

Field of Ecology

Ecology is interrelated with the 5 levels of organization of matter: organisms, populations, communities, ecosystems, or Biosphere.

Bodies (Organisms):

The unity of life, represented in each species, from the...