Iron-deficiency anemia can cause fatigue (tiredness), shortness of breath, chest pain, and other symptoms. Severe iron-deficiency anemia can lead to heart problems, infections, problems with growth and development in children, and other complications.
Semantics is the study of meaning. It is a wide subject within the general study of language. An understanding of semantics is essential to the study of language acquisition (how language users acquire a sense of meaning, as speakers and writers, listeners and readers) and of language change (how meanings alter over time).
Semantics is the study of the meaning of words and phrases. Semantics covers vocabulary, which is affected by SES. Children of high SES have larger expressive vocabularies by the age of 24 months due to more efficient processing of familiar words.