Write your answers to the following questions in the space below.  Please label your answers as (a), (b) and (c). The planaria, a free-living platyhelminth, does gas exchange across their surface of the body and does not have any specialized gas exchange structures. Yet it is not constrained to having cell layers that are only one cell layer thick like the sponges and cnidarians. a) In order to overcome the constraint that diffusion places on a body plan without a specialized gas exchange structure, would the ratio of the body surface area to the body volume need to be high or low?     b) Explain how the flatworm’s way of doing gas exchange constrains their body plan so that they can provide effective gas exchange to keep the animal alive.           

Rashad is an active 1-year-old child. He has a regular routine for playing, eating, and sleeping, and he is mostly in a positive mood. He is observant and readily approaches and adapts to new situations. According to psychiatrists Stella Chess and Alexander Thomas’s classification of basic types of temperament in children, Rashad can be considered a(n)

A six-year-old child with a mental age of 6 would have an IQ of

In the context of human development, ________ refers to an individual’s environmental and social experiences.

Juliet, a 14-year-old, refuses to go to the annual spring dance held in her school because she has just developed a pimple on her chin, and she is sure everyone will talk about it behind her back. Her behavior illustrates

Intellectual disability is a condition of limited mental ability in which an individual has an IQ of ________ and has difficulty adapting to everyday life.

________ is often termed “maturation” because it involves an unfolding of biological processes.

When Justin, a teenager, told his parents that he wanted to learn an extracurricular activity, his parents gave him the liberty to choose any activity of his choice. However, they restricted him from choosing extreme sports. In this scenario, Justin’s parents are following the ________ parenting style.

Maturation of the T cells takes place in the

A child with a mental age of 9 and a chronological age of 12 has an IQ of