Typhoid fever is caused by which bacterium? MCQ with Answer and Explanation

Explanation:
Chloroplasts are present only in the green, photosynthetic parts of plants, not in root cells or non-green tissues. Plant cells typically have a single, large central vacuole occupying most of the volume, whereas animal cells have small, temporary vacuoles. Centrioles are absent in higher plants (angiosperms and gymnosperms) but present in animal cells and some lower plants. Only statement 2 is correct.

Explanation:
Ion exchange chromatography separates proteins based on their net surface charge; positively charged proteins bind to cation exchangers, negatively to anion exchangers. Gel filtration separates by size, affinity by specific binding, SDS-PAGE by molecular weight.

Explanation:
Syphilis is caused by the spirochete bacterium Treponema pallidum, typically transmitted through sexual contact. It progresses through primary, secondary, latent, and tertiary stages, potentially causing severe neurological and cardiovascular damage if untreated. Gonorrhea is by Neisseria gonorrhoeae, herpes by HSV, chlamydia by Chlamydia trachomatis. Penicillin is an effective treatment.