BESC 204 EXAM 2 QUESTIONS WITH DETAILED RATIONALES COVERING OOMYCETE SEXUAL REPRODUCTION (ANTHERIDIUM/OOGONIUM), PLASMODIA VITICOLA & GRAPE DOWNY MILDEW, OBLIGATE PATHOGENS VS. OBLIGATE BIOTROPHS, FLAGELLAR ULTRASTRUCTURE (WHIPLASH VS. TINSEL), GERM THEOR

BESC 204 EXAM 2 QUESTIONS WITH DETAILED RATIONALES COVERING OOMYCETE SEXUAL REPRODUCTION (ANTHERIDIUM/OOGONIUM), PLASMODIA VITICOLA & GRAPE DOWNY MILDEW, OBLIGATE PATHOGENS VS. OBLIGATE BIOTROPHS, FLAGELLAR ULTRASTRUCTURE (WHIPLASH VS. TINSEL), GERM THEORY OF DISEASE, BACTERIAL PEPTIDOGLYCAN CELL WALL ARCHITECTURE, AND ANTIBIOTIC MECHANISMS (PENICILLIN, CEPHALOSPORIN, GRISEOFULVIN'S MICROTUBULE INHIBITION, AND CILOFUNGIN'S ANTI-CANDIDA ACTIVITY). 1. Which of the following is considered the "male" part of oomycete sexual reproduction? A) Oogonium B) Plasmodia viticola C) Antheridium D) Sporangium Correct Answer: C) Antheridium Rationale: The antheridium is specifically identified as the "male" part of oomycete sexual reproduction. The oogonium would be the female counterpart. Plasmodia viticola is a fungus that causes Grape Downy Mildew, and sporangium is a spore-producing structure. ________________________________________ 2. What disease is caused by Plasmodia viticola? A) Potato Late Blight B) Grape Downy Mildew C) Wheat Rust D) Corn Smut Correct Answer: B) Grape Downy Mildew Rationale: Plasmodia viticola is the fungus specifically identified as causing the disease Grape Downy Mildew. Potato Late Blight is caused by Phytophthora infestans, while rusts and smuts are caused by other fungal pathogens. ________________________________________ 3. Which type of pathogen can only complete their development on a living host? A) Facultative saprophyte B) Obligate pathogen C) Facultative parasite D) Necrotroph Correct Answer: B) Obligate pathogen Rationale: An obligate pathogen is defined as a pathogen that can only complete their development on a living host. Examples include rusts. Facultative saprophytes can live on dead organic matter, facultative parasites can live as saprophytes but prefer parasitic lifestyle, and necrotrophs kill host tissue and feed on dead cells. ________________________________________ 4. Which of the following is an example of an obligate pathogen? A) Plasmodia viticola B) Penicillium C) Rusts D) Candida albicans Correct Answer: C) Rusts Rationale: Rusts are explicitly given as examples of obligate pathogens. Plasmodia viticola is an obligate biotroph, Penicillium is a saprophytic fungus, and Candida albicans is an opportunistic pathogen. ________________________________________ 5. Obligate biotrophs extract nutrients only from: A) Dead plant tissues B) Living plant tissues C) Soil organic matter D) Animal tissues Correct Answer: B) Living plant tissues Rationale: Obligate biotrophs are defined as pathogens that extract nutrients only from living plant tissues and cannot grow apart from their hosts. They do not feed on dead tissues, soil organic matter, or animal tissues. ________________________________________ 6. Which type of flagellum has no hair-like structures? A) Tinsel flagella B) Whiplash flagella C) Lophotrichous flagella D) Peritrichous flagella Correct Answer: B) Whiplash flagella Rationale: Whiplash flagella are specifically described as having no hair-like structures. Tinsel flagella have many hair-like structures attached. Lophotrichous and peritrichous refer to arrangements of flagella on bacteria. ________________________________________ 7. Which type of flagellum has many hair-like structures attached? A) Whiplash flagella B) Tinsel flagella C) Monotrichous flagella D) Amphitrichous flagella Correct Answer: B) Tinsel flagella Rationale: Tinsel flagella are characterized by having many hair-like structures (mastigonemes) attached to them. Whiplash flagella are smooth with no hair-like structures. Monotrichous and amphitrichous describe bacterial flagellar arrangements. ________________________________________ 8. The germ theory states that: A) All diseases are caused by genetic mutations B) All contagious diseases are caused by microorganisms C) All diseases are caused by environmental factors D) All microorganisms cause disease