The pericardial cavity separates the parietal and visceral pericardium
The similarity between the sea star larva of modern times and some primitive vertebrae larvae suggests that they <span>share a common ancestor with sea stars.</span>
Answer:
food pellet
Explanation:
Unconditioned stimulation is a stimulus that causes an automatic and natural response to a specific situation. In the case of the situation shown in the question, the unconditioned stimulus is the food pellet, because the rats when they smelled vanilla knew they would get a food pellet in the left corner of the cage, so when the rats felt the vanilla smell automatically shifted to the left corner of the cage, even if they didn't receive the food pellet.
It is D. If you ask scientific questions and reason with what the project is, you can get the answer. Hope I helped!
Answer:
B
Explanation:
Chloroplasts have two membranes: <u>external and internal membrane.</u> These membranes contain 60% of lipids and 40% of proteins, just like the typical cell membranes. The <u>inner or internal membrane</u> is virtually non-permeable to any substances but it has transport proteins, on the other hand, the <u>outer or external membrane</u> is permeable to most of the small molecules
