Answer:
Sonic Hedgehog.
Explanation:
Sonic hedgehog is a secreted protein that in humans is encoded by the SHH gene. It is the best studied ligand of the hedgehog signaling pathway, others being desert hedgehog (DHH) and Indian hedgehog (IHH). It plays a key role in the development of animals, from insects to mammals. In vertebrates, it is involved in organogenesis, including the growth of digits on limbs and the organization of the brain.
Sonic hedgehog has also been shown to act as an axonal guidance cue. It has been demonstrated that SHH attracts commissural axons at the ventral midline of the developing spinal cord. Specifically, SHH attracts retinal ganglion cell (RGC) axons at low concentrations and repels them at higher concentrations
Answer:
No cellular energy is needed in the Passive transport.
Explanation:
A movement of atomic molecules and ions throughout the cell membrane is known as passive transport. In this transportation of molecules no cellular energy is used.
As this movement is influenced by the tendency to grow as entropy, the energy is not in need unlike the active transport. Its rate depends on the permeability of cell membrane. There are four types of passive transport- facilitated diffusion, simple diffusion osmosis or filtration.
Answer:
the outer membrane has small organic molecules but the inner membrane is less permeable and studded with transport proteins.
Explanation:
This change best illustrates the 3rd answer choice, Loss of Habitat.
The plants aren't migrating, but are rather only surviving in areas where there is enough moisture to support life. The wildflowers are not adapting to grow in dryer conditions, and the species is not going extinct, as there are still some areas where the plants can get enough moisture.
Hope this helped!
