This practice exam (epreuve zero) in Life and Earth Sciences (SVT) from the EEHB Baccalaureate 2021 session is a comprehensive document containing both the exam questions and detailed answer key. Designed as a preparatory examination, it allows candidates to familiarize themselves with the format and requirements of the official exam.

Part A is dedicated to resource evaluation. The knowledge assessment includes an MCQ exercise covering four topics: cell biology (cellular exchanges through endocytosis), genetics (dihybrid cross proportions with dominance and independent genes), immunology (B lymphocyte maturation in bone marrow), and disasters (human origins). A document analysis exercise focuses on blood sugar regulation, including plotting and analyzing the glycemia variation curve after glucose syrup ingestion.

The practical skills assessment includes two exercises. The first covers cell biology: identification, diagramming, and annotation of mitochondria and cell nucleus ultrastructures. The second exercise addresses meiosis, with identification of different phases, description of anaphase, and chronological ordering of cell division stages.

Part B evaluates competencies through a problem-based scenario centered on raising awareness about genetic anomalies and immune system disorders. The scenario features a man suffering from vitiligo. Candidates must:

• Explain in a presentation why progressive depigmentation cannot be albinism
• Write a scientific text linking vitiligo to immune system disorders (autoimmune disease, melanocyte destruction by abnormal antibodies)
• Design an informative poster to raise public awareness about this condition

The complete answer key is included with detailed evaluation grids. This document is an excellent training tool for Baccalaureate series C and Ti candidates wishing to review cell biology, genetics, metabolic regulation, and immunology.