Pectinate muscles are parallel ridges in the walls of the atria of the heart. The name is due to their resemblance to the teeth of a comb (pecten). The heart is the organ pumps blood to all parts of the body. It is made up of four chambers, that is, right and left ventricles, left and right atria, and the blood vessels, Pulmonary artery, pulmonary vein, aorta, and venacava. An auricles are pouch like structure that increase the total filling capacity of the atrium and also increase the volume of blood that an atrium is able to contain.
Lipids are good for making the cell membrane because they are stronger and block out things that should not be getting in out, for instance lipids mainly only let water and gases pass through.
I had to look for the missing options of this question and here is my answer:
Osteocyte is the term that describes the cells of the bone. These cells are formed in the mesenchyme. Once the bone matures, the processes then take place inside the Lacunae and the Canaliculi, respectively. Therefore, we can say that the structure that allows the provision of nutrients and removal of wastes from osteocytes would be the canaliculi.
