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

Introduction to Giardia duodenalis

• Giardia duodenalis is also known as Giardia lamblia and Giardia intestinalis.
• It is a flagellated unicellular eukaryotic microorganism that colonizes and reproduces in the small intestine.
• It commonly causes a gastrointestinal condition known as Giardiasis.

Classification of Giardia duodenalis

• There are five species of Giardia, of which G. intestinalis infects humans and other mammals.
• G. duodenalis can further be differentiated into seven genotypes (A to G), of which genotypes A and B usually infect humans.

History and Global Distribution of Giardiasis

• It is one of the earliest protozoan parasites to have been

Plasmids pBR322 and pUC18/19

pBR322

pBR322, developed in 1977, is a foundational plasmid in molecular biology. Key features include:

• Size: ~4,361 base pairs (bp)
• Origin of Replication: Allows independent replication within bacteria.
• Selection Markers:
  • ampR: Confers ampicillin resistance.
  • tetR: Confers tetracycline resistance.
• Cloning Sites: Multiple sites for inserting foreign DNA.
• Applications: Gene cloning, expression, and manipulation.

pUC18/19

pUC18/19, derived from pBR322 in the early 1980s, simplifies cloning. Key features include:

• Size: ~2,686 bp
• Origin of Replication: High-copy-number pMB1 ori for increased yield.
• Selection Marker:
  • lacZ: Beta-galactosidase gene; enables blue/white screening for insert identification.
• Cloning Sites: Multiple cloning

Tracheophytes: The Vascular Plants

Key Features of Tracheophytes

• Also known as vascular plants due to their specialized conducting vessels (xylem and phloem).
• Possess true roots, stems, and leaves.
• Exhibit autotrophic nutrition, producing their own food through photosynthesis.
• Develop three primary tissue systems: vascular, ground, and dermal tissues.
• Many species reproduce via seeds, though some reproduce by spores.

Classification of Tracheophytes

• Lycopsida
• Sphenopsida
• Psilopsida

Ferns: Non-Seed Vascular Plants

Characteristics of Ferns

• Comprise approximately 10,000 known species.
• Typically herbaceous and rhizomatous (possessing underground stems).
• Often thrive in warm, humid environments, particularly in tropical forests.
• Possess true roots, stems, and leaves

What is VSG and why is it important in pathogenesis caused by Trypanosoma?

VSG stands for Variant Surface Glycoprotein, and it plays a crucial role in the pathogenesis caused by Trypanosoma, the parasitic protozoa responsible for diseases like African trypanosomiasis.

The importance of VSG lies in its ability to undergo antigenic variation. Trypanosomes have a dense coat of VSG on their cell surface, providing a protective barrier against the host's immune system. The parasite, however, can continually switch between different VSG variants, making it challenging for the host's immune system to mount an effective and lasting defense.

This antigenic variation is a key survival strategy for Trypanosoma during the course of infection. As the immune...

Corn
Kingdom Plantae
Traqueofita Division
Angiosperm Class
Subclass Monocotyledoneae
Cereals Order
Family Poaceae (Gramineae)
Scientific name (genus and species) Zea mays

Bean

1. Bioelements O biogenic elements.

Are the chemical elements that are part of living matter. We found about 70 chemical elements forming part of living matter, these are in various proportions and not all are present in all living things. In accordance with its wealth divide:
Bioelements-primary.
Bioelements-side.

• Bioelements Primary: These are found in greater proportion, are present in all biomolecules. Represents around 95% by weight of living matter. They are the C, O, H, N and to a lesser extent P and S.
  These items have been selected among all those who constitute the Earth's crust to form living matter, although except oxygen are the most abundant, possessing features among which are the following:

1-have incomplete outer electron...

Organelles and Functions:

• Rough Endoplasmic Reticulum: Responsible for the assembly of many proteins • Cell Membrane: Controls the movements in & out of the cell and organelles • Golgi Apparatus: Process and bundle macromolecules like proteins and lipids • Mitochondria: Perform cellular respiration 0 Breaks nutrients into energy • Nucleus: Contains a majority of the genetic material • Nucleolus: Rewrite ribosomal RNA and combine it with proteins • Smooth Endoplasmic Reticulum: Makes cellular products like hormones and lipids • Lysosome: Digestion and waste removal • Flagella: Allows cells to move • Vesicle: Transport vesicles move molecules within the cell • Ribosomes: Makes proteins within cells • Cytoskeleton:...

Photosynthesis: Key Reactions and Processes

Oxygen Release in Photosynthesis: Oxygen is released during the light-dependent reactions of photosynthesis, specifically when water molecules are split (photolysis).

Organelles Involved: The organelles represented are the mitochondria and chloroplast. Photosynthesis occurs in the chloroplast, and cellular respiration occurs in the mitochondria.

Oxygen as a Waste Product: Oxygen (O2) is produced as a byproduct during photosynthesis and is consumed during cellular respiration.

Anabolic and Catabolic Processes: Photosynthesis is an anabolic process (building complex molecules), while cellular respiration is a catabolic process (breaking down complex molecules).

Photosystems: Structure and Location

Photosystems...

The First Cells: Cell Evolution

All organisms that currently inhabit the Earth are related because they come from ancestral cells that emerged more than 3,800 million years ago as a result of a slow evolutionary process of organic molecules accumulated in the primeval oceans. It is believed that the decisive moment in the origin of cells was the appearance of a biological membrane.

• The membrane separated the external environment from the internal environment, which favored the existence of a rudimentary metabolism that enabled the ancestral cells to get energy (via nutrition) and use it to reproduce and respond to environmental changes.

Because they originated in a sea of organic molecules, the first cells were probably anaerobic fermentative