______ are proteins that bind to foreign proteins which invade the body.Multiple choice question.BuffersHormonesEnzymesAntibodies

Proteins that bind to antigens and thus prevent their attack on target cells are called _____.Multiple choice question.enzymesbuffersantibodiesneurotransmitters

Foreign cells that enter human body have unique cell surface proteins, known as ________, which stimulate body's defense to attack.Group of answer choicesleukocytesantibodiesantigensplatelets

Membrane proteins that bind to a signal on the outside and trigger a response on the inside of the cell are called _____ proteins.Multiple choice question.junctiontransportreceptor

The bond between amino acids within a protein molecule is called a(n) ______ bond.Multiple choice question.peptidehydrogenionicphosphodiester

The receptors to which animal virus attachment proteins usually bind are _______________________.Group of answer choicescarbohydratesproteinslipidsnucleic acidsglycoproteins