Mycology and Plant Biology Quiz

General Botany

• Presented by Prof. Nivien Nafady, Botany & Micro Dept., Faculty of Science, Assiut University, Assiut, Egypt
• This presentation is about the classification of living organisms

Introduction

• The human mind naturally classifies and differentiates things, which is essential for understanding and manipulating the world.
• The topic of interest covers viruses, viroids, prions, rickettsiae, mycoplasma, bacteria, cyanobacteria, fungi, algae, and lichens.
• Methods of classifying animals and plants.

Microorganisms

• Microorganisms are single-celled organisms too small to be seen with a light microscope.
• Bacteria are the smallest living organisms visible under a microscope
• Viruses are smaller but are not considered living organisms.
• Viruses can be prokaryotic (lack a true nucleus and nuclear membrane) or eukaryotic.
• Classification is based on structure and function.
• Whittaker's 5 Kingdoms (Plants, Animals, Fungi, Protista, Monera)
• Phylogenetic classification based on relationships in nucleic acid sequences.
• Three Domains (Archaea, Bacteria, and Eukarya)

Classification of The Living Organisms

• The earliest classification system, created by Carl Linnaeus in 1707, categorized living things into plants and animals based on observable differences (e.g., movement, mode of nutrition) :
• Animals are heterotrophic (cannot produce their own food); plants are autotrophic (can produce their own food)
• Animals usually have a definite shape; while plants don't.
• Animal cells lack a cell wall but plant cells have a rigid cell wall.
• Living organisms were grouped into three kingdoms in 1866 by Ernst Haeckel (Zoologist)- Protista, Plantae, and Animalia.

The five kingdoms

• In 1956, Copeland proposed a system that included four kingdoms: Monera (prokaryotes), Protista (unicellular eukaryotes), Animalia, and Plantae
• In 1969, Whittaker proposed a five-kingdom system: Monera (prokaryotes), Protista (mostly unicellular eukaryotes), Fungi (multicellular, non-photosynthetic eukaryotes), Animalia (multicellular, heterotrophic eukaryotes), and Plantae (multicellular, autotrophic eukaryotes).
• Mode of nutrition: ingestion (animals) / absorption (fungi) / photosynthesis (plants)

Viruses

• Viruses are non-cellular infectious agents.
• Viruses require host cells for replication
• Viruses are very small, requiring an electron microscope for visualization
• Viruses are composed of nucleic acid (RNA or DNA) encased in a protein coat (capsid).
• Viruses may or may not have an outer lipid envelope.
• A complete, infective virus particle outside a host cell is called a virion.
• Viruses are described as having both characteristics of living and non-living things.
• Non-living characteristics: crystallization and no metabolism outside a host cell
• Living characteristics: ability to multiply and cause disease inside a host cell; the presence of a period of incubation; and the possibility of mutation, enzyme production
• Classification of viruses :
• can be classified according to the host they infect (e.g., plants, animals, bacteria, etc.)
• according to the types of nucleic acid that compose the virus

Bacteriophages

• Bacteriophages are viruses that infect bacteria.
• Bacteriophages have a head and a tail.
• The head is filled with DNA.
• The tail carries the DNA to the host cell.

Composition of Viruses

• Viruses are composed of nuclei acids (DNA or RNA) which can not both exist in the same virus
• The protein coat surrounding the nucleic acid called a capsid, which is composed of many subunit-like structures called capsomeres.

Mechanisms of Virus Infection

• Viruses infect host cells through stages: adsorption, penetration, blocking of information, synthesis of viral components, and release of new viruses.
• Interaction occurs when the virus attaches to a cell using surface receptors
• Host make viral genetic materials and proteins
• New viral particles exit, repeating the infection cycle.

General Microbiology (PhB-104)

• Presentation by Nivien A. Nafady, Prof. of Microbiology, Botany and Microbiology Dept., Faculty of Science, Assiut University

Algae, Fungi, Bacteria

• Descriptions of images, details and classification of the organisms

Bacteria

• Bacteria are single-celled organisms with a prokaryotic cell structure (lacking a membrane-bound nucleus and organelles).
• Bacteria have a variety of shapes (coccus, bacillus, spirillum) and arrangements.
• Bacterial size is micrometric
• Classification based on cell wall composition. (Gram-positive/Gram-negative)
• Cell envelope structure (plasma membrane, cell wall, external structures such as pili, flagella, capsules)
• Internal cellular components (nucleoid, ribosomes, plasmids )

Definitions

• Definitions and descriptions of Mycology, Mycologists, Mycoses, Fungus

Fungi

• Eukaryotic
• Non-vascular organisms; lacks vascular tissues (xylem and phloem) found in plants.
• Have cell walls (chitin)
• Reproduction: both asexual and sexual
• Asexual (budding, fragmentation, fission, sporulation)
• Sexual (plasmogamy, karyogamy, meiosis)
• Nutrients: heterotrophic - either saprophytes (dead organisms) / parasites / symbiosis (with benefit to both organism)
• Growth factors: have an optimum pH requirement for growth and a temperature range.
• Distribution: mostly on Earth in dark and damp environments.

Plant Anatomy

• Presented by Dr. Nivien Allam
• Aims to introduce plant tissues and functions, the anatomy of roots, stems, and leaves, secondary thickening, ecological groups, and adaptations.
• Plant Tissues: simple and complex types; Meristematic and permanent tissues
• Classifications of tissues (permanent/meristematic; simple/complex) in plants; examples of specific tissues. Primary and secondary meristems

Growth Curve (Population Growth of Bacteria)

• A group of bacteria introduced to a favorable environment, grows rapidly in number.
• Population increase usually goes through four phases- lag, log (exponential), stationary, death phases.
• Lag phase: the organisms are adjusting to a new environment before they start growing. During the lag phase the cells change very little.
• Log or Exponential phase: rapid cells growth and population doubles during this phase.
• Stationary phase: growth rate and death rate are same which is limited by various factors like nutrients and space.
• Death phase: death rate surpasses the reproduction rate. The population decreases geometrically in this phase due to various factors like the accumulation of waste products and availability of limiting factors.

Test your knowledge on phloem tissue and mycology, focusing on concepts related to the transport of nutrients in plants and the study of fungi. This quiz covers key terminology and definitions, including the structure and function of phloem and the classification of fungi in biology.