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

Biological Nutrition and Cellular Processes

Nutrition is the set of processes by which bodies exchange matter and energy with their environment to maintain internal organization and carry out their vital functions.

Types of Cellular Nutrient Intake

• Intracellular Digestion: The cell engulfs a food particle into the cytoplasm within a vesicle (phagosome). This vacuole fuses with a lysosome containing digestive enzymes to form a digestive vacuole. Nutrients are digested and pass through the cytoplasmic membrane, while waste is expelled.
• Extracellular Digestion: A lysosome fuses with the plasma membrane, releasing enzymes outside the cell. These enzymes break down large food molecules into smaller fragments that can penetrate the plasma membrane and

Arteriosclerosis vs. Atherosclerosis

These terms are similar, but distinct. Arteriosclerosis is a general term for hardening and loss of arterial elasticity. Atherosclerosis is hardening specifically caused by atherosclerotic plaques.

Heart Conditions

Heart Murmurs

Heart murmurs are pathological noises heard during auscultation, caused by increased flow through normal valves, valve alterations, intracardiac abnormalities, or extracardiac issues. They can be systolic, diastolic, or continuous.

Tachycardia

Tachycardia is an increased heart rate, specifically above one hundred beats per minute at rest.

Leukemia

Leukemia is a group of malignant bone marrow diseases causing an uncontrolled increase in white blood cells (WBC), often appearing in peripheral...

The Origins of Life and Biological Evolution

About 15 billion years ago, the universe was smaller than an atom and devoid of matter. Life arose soon after Earth formed, about 3.5 billion years ago. Since that time, life began to evolve.

Defining Biological Evolution

Biological evolution is the process of anatomical and physiological changes experienced by populations of living things, which results in the formation of new species.

Human Evolution: A Unique Process

Human evolution is part of the general evolutionary process, but humanity is a unique species within the process of natural evolution.

Foundational Theories of Evolutionary Change

Various theories of evolution attempt to explain this mysterious unfolding of life.

Lamarckism: Acquired Characteristics

Jean-...

Main Characteristics of DNA Replication

• Semiconservative: Each new DNA molecule is formed by an original DNA strand and one newly synthesized strand. Synthesis occurs by the addition of mononucleotides in the 5' to 3' direction.
• Bidirectional: From a single origin, two replication forks move in opposite directions. In bacterial viruses, there is a single starting point, while in eukaryotes, there are several called replicons. Each DNA fragment is replicated from a single origin.
• Semi-discontinuous: In one strand (the leading strand), fragments are synthesized continuously. In the other strand (the lagging strand), synthesis is discontinuous, meaning small fragments are synthesized separately and then joined together. These are known as Okazaki

Water Properties

• Water behaves like a dipole: OH bonds shift to oxygen, creating partial charges.
• Hydrogen bonds form between water molecules.
• Water is a great solvent due to hydration atmospheres.

Osmotic Pressure

• Hypertonic: Increased osmotic pressure, higher concentration.
• Hypotonic: Lower osmotic pressure, lower concentration.

Disaccharide Characteristics

1. Hydrolyzable into subunits.
2. Sweet taste.
3. Crystallizable.
4. Water-soluble.
5. No reducing power loss.

Hemiacetal Linkage

Cellulose

Cellulose consists of parallel chains joined by hydrogen bonds, forming microfibrils and fibers. This structure makes cellulose water-insoluble and rigid, providing structural support in plants. Humans and animals lack enzymes to break down cellulose, but some organisms (e.g.,...

The Vital Role of Algae in Aquatic Life

Algae are a very large group of photosynthetic protoctists dependent on the aquatic environment. They all possess chlorophyll pigments, which give them their coloration, and their cells have a cell wall composed of cellulose. Algae colonize all aquatic habitats.

Ecological Importance and Reproduction

Through photosynthesis, algae form the first link in the food chain in ecosystems, discharging large amounts of O₂ into the atmosphere.

Reproduction is typically:

• Asexual: By binary fission or fragmentation.
• Sexual: Involving the interference of gametes and meiospores.

Most algae are microscopic, unicellular, or colonial, forming phytoplankton that floats in the upper, illuminated layers of the oceans and is of...

Advances in Stem Cells and Regenerative Medicine

Recent breakthroughs in stem cell research offer immense potential for tissue regeneration, curing diseases like cancer, and even slowing the aging process.

Key Concepts in Cellular Biology and Genetics

• Cloning: The process of creating an exact genetic copy of an organism or cell.
• Embryonic Stem Cells: These remarkable cells possess the ability to reproduce and differentiate into various specialized cells and organs.
• Therapeutic Cloning: A technique where the development of an individual is intentionally halted to obtain stem cells from a very early-stage embryo, known as a blastocyst.
• Totipotent Stem Cells: Cells capable of dividing and differentiating into any cell type required by an organism.
• Pluripotent

Biotechnology and Genetic Engineering

Biotechnology is a scientific discipline based on the use of living organisms to facilitate chemical processes for industrial purposes. Genetic engineering is a branch of genetics focused on the study and manipulation of DNA.

Medical Applications

• Pharmaceutical Products: Mammalian protein production, such as insulin, is achieved in microorganisms using genetic engineering techniques.
• Gene Therapy: The treatment of human genetic diseases by identifying and modifying the specific genes responsible for such conditions.
• Vaccine Production: Vaccines are suspensions of killed or attenuated pathogens that, when injected, induce immunity against specific diseases.
• Transgenic Animals: Used for basic biomedical research,

Noncyclic Phosphorylation

The arrangement of the pigment-protein complexes, Photosystems I and II, both electron carriers in the electronic transport chains and ATP synthase enzymes, is necessary to maintain a specific spatial arrangement in the thylakoid membrane, which enables ATP synthesis. The mechanism of ATP synthesis is nearly identical to that of the mitochondria; it depends on the existence of the ATP synthase enzyme complex on the stromal face of the thylakoid membrane. Proton pumping into the thylakoid, performed by several protein complexes of the light phase, generates a proton-motive force gradient necessary for synthesis. In the chloroplast, it is known that each ATP synthesis catalyzed by the stromal portion F1 is associated...

Transport of Water and Salts

Transpiration

The force that causes water to ascend from the soil to the leaves is called transpiration. As water evaporates from the leaf, it creates a suction force that draws more water into the roots, allowing it to climb through the interior of the stem to replace the evaporated moisture. This process is known as the transpiration stream, driven by the cohesive forces between water molecules.

Water loss through transpiration is strictly regulated by the specialized cells that surround the stomata.

The Importance of Photosynthesis

Energy flows through the biosphere, with approximately 1% of solar radiation captured by plants during photosynthesis. Plants store light energy in chemical form within their cells, specifically...