Bread “rises” when tiny gas bubbles are formed in bread dough. Dough is made with sugar, flour, water and yeast. Bakers have been using yeast to raise their bread for 100s of years. Yeast are unicellular organisms.

The skeletal system performs a variety of functions that are crucial to maintaining life processes. what function is performed in the bone marrow, but not in the ossified bones of the skeleton? a oxygen transportation c mineral storage b. muscle attachment d red blood cell production

The diagram shows a chicken embryo and a human embryo

Which of the following is a feature of all cells? o a. all cells have a nucleus. o b. all cells have dna for at least part of their life cycle. het . o c. all cells are spheres. o d. all cells have a rigid cell wall.