Notes, summaries, assignments, exams, and problems for Biology

Physical Assessment of a Patient with Cancer

Skin

• Inspection: Color, integrity, turgor, humidity, temperature.
• Check for: Injuries (type, size, and location), purpura, petechiae, edema, and appearance of nails.

Head and Neck

• Inspect: Face (asymmetry), eyes, mouth, trachea, maxillary sinuses.
• Palpation: Thyroid.

Thorax

• Inspection: Breathing movements and rate.
• Palpation, percussion, auscultation: Tone, intensity, and duration of breath sounds.

Breasts and Armpits

• Inspection and palpation.

Cardiovascular

• Inspection: Tremors and palpitations in the chest.
• Auscultation, palpation, blood pressure.

Musculoskeletal

• Inspection: Hair distribution, abnormal masses or lesions, asymmetries, nodules.
• Palpation: Painful masses, joint range of motion.

Neurologic

• Presence of

Types of Transplants

• Autotransplant: Donor and recipient are the same patient. Used for tissues or organs such as skin portions or bone.
• Isotransplant: Donor and recipient are identical twins. No rejection occurs.
• Xenotransplant: Donor and recipient are distinct species (e.g., using pig heart valves in humans). There is a risk of rejection.
• Allogeneic Transplant: Donor and recipient are of the same species but genetically different. This is the most common type, and there is a risk of rejection.

Immune Rejection Problems

Our immune system distinguishes self from foreign. If it locates foreign tissue, it attempts to destroy it. This is of great importance when dealing with viruses and bacteria, but it also applies to donor tissue. It is crucial that... Continue reading "Medical Transplants and Regenerative Medicine" »

Nutrition: Function and Importance Nutrition includes all processes to get the materials of development and the energy we need to live like .--- La Nutricion: Nutrition is a long process. One step is to take food. Function in the 4 processes involved Nutrition: Circulation - the digestive process, respiration, and excretion Feeding and Nutrients To live, we need the nutrients that food contains. The main groups are carbohydrates, fats, proteins, water, vitamins, and minerals - A diet is complete when it contains all types of nutrients. A balanced diet is when it gives us the necessary amount of each nutrient.

Public Health Protection Strategies

Water Treatment and Disinfection

Water must be potabilized (made safe for drinking). This involves two main processes:

1. Pretreatment: This process is intended for physical-chemical correction and the removal of solid particles (e.g., decantation, filtration, aeration).
2. Disinfection: The objective is the elimination of pathogenic microorganisms. Disinfection may be done using chlorine, ozone, or ultraviolet radiation.

Waste Management and Treatment

Wastewater: This includes domestic and industrial sources, rainwater, and street washings. This water needs to undergo a preliminary purification treatment to remove all hazardous components.

Solid Waste: Municipal and industrial solid waste is collected and transported... Continue reading "Public Health Strategies: Water, Waste Management, and Immunization" »

Functions of Muscle Tissue

• Production of body movements
• Stabilization of posture
• Volume regulation of the body
• Movement of chemicals in the body
• Production of heat

Properties of Muscle Tissue

• Electrical excitability
• Contractility
• Extensibility
• Elasticity

Types of Muscle Tissue

There are three types of muscle tissue: striated skeletal, striated cardiac, and smooth.

• Striated skeletal muscle: Called skeletal because the function of these muscles is to move the bones; it often works on a voluntary basis.
• Heart muscle (myocardium): Is located in the heart and is part of its wall. Its movement is involuntary.
• Smooth muscle: Is part of the walls of blood vessels, airways, and some guts. Almost always, this type of muscle movement is involuntary.

Structure of Striated

What is Embryology?

Embryology is the branch of biology that studies the development of an organism from a fertilized egg. It encompasses several key concepts:

• Ontogeny: The transformations that the embryo undergoes during development.
• Phylogeny: The evolutionary history of a species.

Historical Theories of Development

Historically, two main theories attempted to explain embryonic development:

• Preformationism: This theory argued that a miniature version of the organism, called a "homunculus," was present in either the sperm or the egg. Scientists who believed in this were called "animalculists." In 1699, Danlenpatius proposed this theory.
• Epigenesis: This theory proposed that adult body structures were not preformed in the gametes but developed gradually.

Genetics: The Study of Gene Inheritance

Genes are transmitted according to defined rules or laws. Genes are located on chromosomes, which are cellular structures. Sex is determined by specific genes or chromosomes in most living organisms.

Key Genetic Terms

• Genotype: The genetic constitution of an individual, referring to a specific character or the entire set of genes.
• Phenotype: The external expression of the genotype; the observable characteristics of an individual.
• Alleles: Variants that a gene may present. For each gene, an individual has a pair of alleles, often represented by letters.
• Homozygous: An individual having two identical alleles for a specific gene.
• Heterozygous: An individual carrying two different alleles for a specific gene.

Mendelian

Immunodeficiencies: Types and Causes

An individual suffers from an immunodeficiency when their immune system is unable to effectively combat or stop an infection. These conditions are broadly categorized into two main types: congenital and acquired.

Congenital Immunodeficiencies

Congenital immunodeficiencies are genetic and inherited conditions. They arise from failures in the synthesis of the complement system or from the abnormal development of lymphoid organs. These can manifest as:

• B Lymphocyte Defects

  These are due to defects in B lymphocytes, which are unable to produce normal antibodies or produce them in insufficient quantities. Symptoms typically do not appear until after 6 months of age.

• T Lymphocyte Defects

  Defects in T lymphocytes are

Fundamentals of Protein Synthesis

1. Information for Protein Synthesis

Question: Which part of the cell contains the information needed to synthesize a protein?

Answer: Deoxyribonucleic Acid (DNA), primarily located in the nucleus.

2. Cellular Organelles for Protein Production

Question: What are the cellular organelles responsible for making proteins, and where are they located in the cell?

Answer: Ribosomes, which are primarily located in the cytoplasm and on the endoplasmic reticulum.

3. Understanding RNA (Ribonucleic Acid)

Statement: RNA, or Ribonucleic Acid, plays a crucial role in gene expression and protein synthesis.

4. RNA Nucleobases

Question: Name the four nucleobases found in RNA.

Answer: Cytosine, Guanine, Adenine, and Uracil.

5. The Process

Fertilization

Fertilization is the fusion of male and female gametes, initiating the process of reproduction. It's important to note that fertilization of the egg is not immediate upon contact.

Human Fertilization

In humans, fertilization occurs when a sperm and egg unite in the fallopian tubes after sexual intercourse. Humans develop from the union of these two tiny cells. Mature eggs measure approximately 0.135 mm in diameter, while sperm are even smaller. Each ejaculation can contain between 120 and 600 million sperm. The union of these cells has the potential to create a new human being with extraordinary abilities.

Zygote

In biology, a zygote is the cell formed by the union of male and female gametes during sexual reproduction in organisms... Continue reading "Human Reproduction: From Fertilization to Embryonic Development" »