In 2001, Bacillus anthracis endospores were sent in letters to various locations in the United States. The recipients of the letters inhaled the spores and were infected with this pathogen; five people died as a result. Which of the following statements are true about bacterial endospores? Select all that apply. Check all that apply. View Available Hint(s) Endospores are highly durable dehydrated cells with thick cell walls. Endospores are reproductive structures. Endospores can survive extreme heat, lack of water, radiation, and exposure to many toxic chemicals. Both Gram-positive and Gram-negative organisms form true endospores.