I. Each carbon atom can form single bonds with up to four other carbon atoms. II. Each carbon atom can form double bonds with up to two other carbon atoms. III. Carbon atoms can join together to form chains or rings. IV. A single molecule of some compounds can contain thousands of carbon atoms.
Answer:
All the given choices
Explanation:
Carbon is a very interesting element which is the backbone of most organic compounds.
Organic compounds are made up of carbon. Carbon forms a wide range of compound due to the following properties;
- An atom of carbon has 4 valence electrons and can bond with 4 other carbon.
- Carbon can form single, double and triple covalent bonds.
- They can join together to form rings or chains.
Answer:
Melting of glaciers and ice sheets will cause coastlines to shrink and increase flooding.
But what is the question are you like not sure about it or what
Answer:
(d) Electrical-->Chemical-->Electrical
Explanation:
A nerve impulse is the transmission of an electrical change along the neuron's membrane from the point at which it is stimulated (synapse). The normal direction of impulse in the body is from the cell body to the axon. This nerve impulse, or action potential, is a sudden and rapid change in the transmembrane potential difference.
Normally, the membrane of the neuron is polarized at rest, which means that the ionic constitution of the medium internal to the membrane is different from the external medium, which generates different electrical charges in one medium and the other, so this difference, ie , the potential during rest is negative (-70 mV). The action potential thus consists of a rapid reduction of membrane negativity to 0mV and inversion of this potential to about + 30mV, followed by a rapid return to values slightly more negative than the resting potential of -70mV.
Nervous impulse or action potential, therefore, is a phenomenon of an electrochemical nature and occurs due to changes in the permeability of the neuron membrane. These permeability modifications allow ions to pass across the membrane. Since ions are electrically charged particles, changes also occur in the electric field generated by these charges.
Thus, we can say that the correct answer to this question is: Electrical -> Chemistry -> Electrical
The four levels of protein structure are distinguished from one another by the degree of complexity in the polypeptide chain. A single protein molecule may contain one or more of the protein structure types: primary, secondary, tertiary, and quaternary structure. 1. Primary Structure: describes the unique order in which amino acids are linked together to form a protein.
2. Secondary Structure: refers to the coiling or folding of a polypeptide chain that gives the protein its 3-D shape. There are two types of secondary structures observed in proteins. One type is the alpha (α) helix structure. This structure resembles a coiled spring and is secured by hydrogen bonding in the polypeptide chain. The second type of secondary structure in proteins is the beta (β) pleated sheet. This structure appears to be folded or pleated and is held together by hydrogen bonding between polypeptide units of the folded chain that lie adjacent to one another
3. Tertiary Structure: refers to the comprehensive 3-D structure of the polypeptide chain of a protein.
4. Quaternary Structure: is the structure of a protein macromolecule formed by interactions between multiple polypeptide chains. Each polypeptide chain is referred to as a subunit. Proteins with quaternary structure may consist of more than one of the same type of protein subunit.
