Answer:Small hydrophobic molecules and gases like oxygen and carbon dioxide cross membranes rapidly. Small polar molecules, such as water and ethanol, can also pass through membranes, but they do so more slowly.Semipermeable membranes, also termed selectively permeable membranes or partially permeable membranes, allow certain molecules or ions to pass through by diffusion.
Explanation: hope that helps
Answer: Bundles of axons in the central nervous system are called a "tract"
Explanation:
Axons(nerve fiber) consist of long slender projection of neurons or nerve cells that conduct and transmit impulses away from the neuron or nerve cell body. Axons are surrounded by endoneurium layer which contain protein fluid that surround each axon.
Bundles of axon in the CNS is known as tract. We have ascending tracts and descending tracts. The ascending tracts function are to conduct and carry impulses along the spinal cord to the brain while the descending tracts transmit and carry the impulses from the brain to lower regions (downward) of the body. Tracts are identified by their origin (where the bundle start) and also the end/termination of axon bundle.
The largest tracts are fasciculi gracilis and cuneatus which are known as ascending tracts.
Double fertilizer in a plant
Fatty acids aren't pure fat and same for glycerol molecules. You may not be consuming straight fat, but things that create fat in your system.
