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

Key Differences Between Bacteria, Archaea, and Eukarya

Cellular Structure

Bacteria: Lack a nuclear membrane, rarely have membrane-bounded organelles, cell walls are constructed of peptidoglycan, possess a single RNA polymerase, and contain histone-like proteins.

Archaea: Lack a nuclear membrane, rarely have membrane-bounded organelles, cell walls are constructed of various materials, possess RNA polymerase II, and contain histones.

Eukarya: Contain a nuclear membrane, possess membrane-bound organelles, some have cell walls, possess RNA polymerase 1, 2, and 3, and contain histones.

Koch's Postulates and Bacterial Shapes

Koch: Discovered Bacillus anthracis (anthrax) and Mycobacterium tuberculosis. His postulates are:

1. Microbes are present in all cases

The Sounds of Language

A Guide to Phonetic Symbols

Consonants

Cellular Respiration

Glycolysis

• Enzymes break down a 6-carbon glucose molecule into two 3-carbon pyruvate molecules.
• A small amount of ATP is synthesized through substrate-level phosphorylation, an enzyme-catalyzed reaction transferring a phosphate group from a substrate to ADP.

Oxidative Phosphorylation

• High-energy electrons are delivered to oxygen through a series of electron carriers in the electron transport system.
• The free energy released by electron flow generates an H+ gradient via chemiosmosis.
• ATP synthase utilizes the H+ gradient as the energy source for ATP production.

Reaction Locations

• Glycolysis: Occurs in the cytosol.
• Pyruvate oxidation and citric acid cycle: Take place in the mitochondrial matrix.
• Electron transfer system and ATP synthase

Gene Pool

The gene pool is the sum of all genetic information carried by all the individuals of a population.

Mutations

Mutations are the ultimate source of all genetic variation, and are the result of random changes in DNA sequences.

Gene Flow

Gene flow is the movement of genes from one population to another. It occurs when individuals migrate from one population to another, thus bringing their genes with them.

Genetic Drift

Genetic drift is a random process where certain alleles are removed from the population by accidental events. It is more likely to affect small populations than larger ones.

Founder Effect

The Founder Effect occurs when a small group of individuals establishes a new population far from existing populations. Because this group is...

Polymers

A polymer is a macromolecule composed of long chains of repeating molecular units known as monomers. Polymers are typically organic compounds formed by joining monomers containing carbon, hydrogen, and other elements. The properties of a polymer depend on its monomers and its spatial structure, which can be a linear chain, a ring, or other more complex configurations.

Types of Polymers

• Natural Polymers: Found in nature and formed by living organisms. Examples include proteins and cellulose.
• Artificial Polymers: Derived from chemically modified natural polymers. Celluloid was the first artificial polymer. Other examples include cellulose nitrate, rayon, and vulcanized rubber.
• Synthetic Polymers: Designed and synthesized by humans. Examples

The menstrual cycle is the process by which people develop female gametes (oocytes, ova) and produce a series of changes designed to establish a possible pregnancy. The beginning of the cycle is defined as the first day of menstruation, and the end of the cycle is the day before the start of the next menstruation. The mean cycle length is 28 days, although this may be longer or shorter.

The first menstruation is termed menarche, and the last is known as menopause. Depending on the changes in the ovary and uterus, the menstrual cycle is divided into two phases:

• Follicular phase: From the first day of menstruation until ovulation, which consists of menstruation and the proliferative phase.
• Luteal phase: From ovulation until the first day of menstruation,

Plant Tissues

Supporting Tissue

Supporting tissue is found in the interior of the plant body. These tissues form the plant skeleton, giving it rigidity and strength. Their cells have very thickened walls.

Types of Supporting Tissue

• Collenchyma: Found in younger parts, consisting of living parenchymal cells reinforced by cellulose in some areas.
• Sclerenchyma: Supporting tissue of the developed parts, consisting of dead cells with thickened walls and lignin. If they are elongated, they are called fibers, and if they are round, they are called stone cells.

Secretory Tissues

Secretory tissues are varied, modified epidermal cells, such as those that accumulate aromatic substances, resin canals, and lactiferous ducts.

Animal Tissues

Epithelial Tissue

Types

Animal Tissues

Epithelial Tissue

Epithelial tissue consists of sheets of densely packed and connected cells that cover internal and external body surfaces.

Simple Epithelia

Simple epithelia are formed by a single layer of cells that can be:

• Flattened, like the endothelial walls of capillaries and the lining of blood vessels, which protect yet allow the exchange of substances.
• Polyhedral (cubic and cylindrical), such as the epithelial lining inside the intestine. Their cells possess microvilli or fingerings on the surface that faces the lumen of the tube.

Stratified Epithelia

Stratified epithelia consist of several layers of cells. Cells in the deepest layer are constantly dividing, and new cells push the older ones upward. The most superficial cells,...

Digestive System

Function

The digestive system is responsible for processing food, absorbing molecules, and eliminating waste.

Types of Digestion

There are two main types of digestion: mechanical and chemical.

System Interactions

The digestive system interacts with the nervous, endocrine, and circulatory systems.

Functional Structure

1. Mouth: Digestion begins in the mouth.
2. Esophagus: Food travels down the esophagus.
3. Stomach: Gastric digestion occurs in the stomach.
4. Small Intestine: Intestinal digestion and absorption take place.
5. Large Intestine: Final absorption and waste processing.

Excretory System Structure

The excretory system plays a crucial role in waste removal.

• Cecum: Follows the ileocecal valve.
• Colon: Divided into ascending, transverse, and descending

Protozoa

Features:

• Microscopic and eukaryotic unicellular organisms.
• Exhibit movement.
• Aquatic, living in aquatic or terrestrial environments.
• Some are free-living; others are parasites.
• Reproduction may be sexual or asexual.

Classification:

• Mastigophora (Flagellates): Possess flagella for locomotion.
• Rhizopods (Sarcodina): Move via pseudopods, extensions of the cytoplasm.
• Ciliophora (Ciliates): Move using cilia.
• Apicomplexa (Sporozoa): Have a complex life cycle; all are parasites.
• Suctoria: Have cilia in their juvenile phase and tentacles in adulthood.

Locomotion: Move by extending cytoplasm externally (pseudopods), into which the rest of the cytoplasm flows.

Nutrition: Engulf organic particles via pseudopods, forming a digestive vacuole. Enzymes digest...