IQ, short for intelligence quotient, is the measure of a person's intelligence. IQ is measured on a numeric scale where 100 is considered average, 140 is genius and scores below 70 represent mental deficiencies. IQ scores are scaled based on age to take differences in children and adult development into consideration. A person with an IQ score of 45 is considered moderately mentally retarded and exhibits several telltale characteristics.

Learning Ability

Learning disabilities are always present in people with IQs around 45. These individuals learn at a significantly slower pace than peers with average intelligence, and they may have greater difficulties with specific subjects. As adults, most of these people have the reading skills of a second- or third-grader at best. Slower-than-average learning, paired with at least two other impairments in areas such as social or self-care skills, are defining characteristics for people with an IQ of 45.

Daily Living Skills

Moderately mentally handicapped individuals can carry out tasks required for daily living, such as brushing their teeth and getting dressed. Some people in this IQ range require moderate supervision to perform these tasks, while others handle them independently. Tasks that are too difficult cannot be carried out without help or supervision. Moderately mentally handicapped individuals function best with strict routines because they are unable to change their behavior to respond to the unexpected.

Social Skills

Moderately mentally handicapped children and adults can function in social settings and participate in simple, structured activities. It is best if these activities are performed in a familiar and closed setting, as too much stimulus can cause overexcitement. Oftentimes these individuals are institutionalized so they get the structure, stability and individual attention they need.

Work Ability

Adults with IQs near 45 can perform vocational work, provided the tasks are fairly simple and straightforward. Repetition helps keep workers on track and focused on their tasks. It is best if moderately mentally retarded people are given nonessential tasks to perform. Household chores or custodial work are two types of jobs a mentally retarded individual could perform.

Delayed Development

Along with the low IQ, mentally handicapped individuals usually exhibit delayed development. During the preschool years, these individuals will have the motor skills of a 3-year-old and may not be speaking yet. Older children have the mental capacity of an 8-year-old and can travel alone only to familiar places. Adults will be capable of caring for themselves with some supervision, but will need help with finances and important decision making.