Anna is observing slides of unlabeled organisms. the organisms are unicellular, have delicate glasslike cell walls with sculpturing, and show all the cell organelles, including chloroplasts. which organism is she observing?

Diatoms

Explanation:

From the description, only diatoms fits perfectly well. Diatoms are easily recognized by their glasslike cell wall.  

the menstrual cycle – higher tier. negative feedback mechanisms affect the production of hormones in the menstrual cycle. oestrogen also stimulates the release of lh (luteinising hormone) from the pituitary gland, which in turn controls the production of progesterone.

your body is trying to warm itself up. or more precisely, sensors in your skin send messages to your brain to generate heat to your body.