If the organism has no natural predators then that organism can start to overpopulate the habitat and use up valuable resources that other organisms, who DO have natural predators, need to survive and repopulate.
Answer:
<u>d. Transport proteins within the membrane serve as a tunnel for molecules to enter the cell.
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Explanation:
Solutes are typically moved across the cell through either passive or active transport. The cells, surrounded by a bilipid layer or plasma membrane is amphiphlic- its polar, hydrophilic lipid heads face outwards, while their non-polar hydrophobic lipid tails face inwards towards each other.
While lipid-soluble molecules move across the layer easily, it is also difficult for charged and also large molecules to move across its surface, into the cell. Transmembrane channels, <u>embedded within the membrane</u>, help to maintain selective permeability as transport proteins, pores and gated channels. Simple diffusion happens as a method of passive transport in cells through plasma membranes.
The solutes travel through the plasma membrane in the process of diffusion from regions of high concentration to regions of low concentration; this occurs without the use of energy. <u>Molecules moving against their concentration require active transport mechanism to cross the membrane</u>.
Radiation. Have a nice day.
<span>Animals and plants have cells that are specialized by the process of differentiation.</span>
Answer: A neuron has three main parts: dendrites, an axon, and a cell body or soma , which can be represented as the branches, roots and trunk of a tree, respectively. A dendrite (tree branch) is where a neuron receives input from other cells. Dendrites branch as they move towards their tips, just like tree branches do, and they even have leaf-like structures on them called spines.
The axon (tree roots) is the output structure of the neuron; when a neuron wants to talk to another neuron, it sends an electrical message called an action potential throughout the entire axon.
The features of neurons help them to carry out their function efficiently:
they have a long fibre (axon) so they can carry messages up and down the body over long distances
in a stimulated neuron, an electrical nerve impulse passes along the axon
the axon is insulated by a fatty (myelin) sheath - the fatty sheath increases the speed of the nerve impulses along the neuron
at each end of the neuron are tiny branches (dendrons), which branch even further into dendrites - the dendrites receive incoming nerve impulses from other neurons
Explanation:
Hope this is helpful!!
