Answer: chloroplast
Explanation: animal cells do not need to produce chlorophyll but plants cells do because the chlorophyll absorbs sunlight for photosynthesis and it is what makes the plant green.
Answer:
In animal field studies, why do scientists usually try to work without making the animals aware that the humans are present? It is necessary to observe the animals without disturbing them. When a controlled experiment is not possible, why do scientists try to identify as many relevant variables as possible?
Answer:
The answer (Image 1) is attached. Since the options weren't provided, I've attached the image of the options, too.
Explanation:
The plasma membrane is composed of phospholipids, a special form of lipids with a hydrophilic head and hydrophobic tail. According to the fluid mosaic model, the hydrophilic heads are positioned towards the outside where they freely interact with the extracellular matrix and cytosol. Whereas, the hydrophobic tails are positioned towards the inside so they aren't exposed to water.
Liposomes are lipid bases particles used for drug and vector delivery. The picture shows a typical liposome.
In the current case, for water to move both outside and inside, hydrophilic heads should be present inside as well as outside the tails.