Alkenes are characterized by the presence of at least one double bond between carbon atoms.

Organic compounds primarily consist of covalent bonds formed between carbon and other atoms.

Covalent bonds are primarily responsible for the strength and stability of polymer chains.

Covalent bonds are primarily responsible for the structure of polymers, linking monomers together.

A peptide bond is a specific type of covalent bond that links amino acids together in proteins.

A peptide bond links amino acids in proteins.

Cellulose is a polysaccharide that provides structural support in plant cell walls.

In n-type semiconductors, electrons are the predominant charge carriers.

In n-type semiconductors, the majority charge carriers are electrons.

Tendons are connective tissues that connect muscles to bones, allowing for movement.

Adipose tissue is a type of connective tissue that stores fat and provides insulation and cushioning.

Diamond crystallizes in a cubic crystal system, specifically in a face-centered cubic lattice.

Beta decay involves the conversion of a neutron into a proton, emitting a beta particle (electron).

Beta plus decay involves the conversion of a proton into a neutron, emitting a positron.

Stratified squamous epithelium is designed to protect underlying tissues in areas subject to abrasion.

Ciliated columnar epithelium is found in the lining of the respiratory tract, where it helps to trap and move particles out of the airways.

Columnar epithelial tissue is found in the lining of the stomach.

Columnar epithelium is specialized for absorption and secretion, often found in the digestive tract.

Simple columnar epithelium is specialized for absorption and secretion, commonly found in the intestines.

When the object is placed beyond 2F, the image formed by a convex lens is real, inverted, and smaller than the object.

A plane mirror always forms a virtual and erect image, which is the same size as the object.

Parasitism is a type of interaction where one organism benefits at the expense of another.

Competition occurs when two species vie for the same limited resources, which can negatively impact both species.

Liquid water exhibits hydrogen bonding due to the attraction between the hydrogen atoms of one water molecule and the oxygen atom of another.

Structural isomerism occurs when compounds have the same molecular formula but different structural arrangements.

CH3NH2 (methylamine) and C2H5NH2 (ethylamine) exhibit structural isomerism as they have different carbon skeletons.

The complex [Co(en)2Cl2]+ can exhibit optical isomerism due to the presence of bidentate ligands (en = ethylenediamine) which can create non-superimposable mirror images.

The complex [Cr(en)2Cl2]+ can show optical isomerism due to the presence of bidentate ligands (en = ethylenediamine) which can create non-superimposable mirror images.

The complex [Cr(en)3]3+ shows optical isomerism because it contains bidentate ligands (en = ethylenediamine) that can create non-superimposable mirror images.

Pivot joints allow for rotational movement, as seen in the neck.