Logic of a solution: *Meiosis is the type of cell division that produces gametes. Animals that reproduce sexually produce sex cells, or gametes. Meiosis is the type of cell division that produces sex cells.*
*(F)*
The original question: *What kind of cell division produces sex cells in animals?
Options:
- (A) complex
- (B) insects
- (C) pollen
- (D) gametes
- (E) sexual division
- (F) meiosis
- (G) reproduction cells
- (H) seeds*

Line 1: *Thyroid hormones increase the rate of metabolism in cells throughout the body. Thyroxine, a thyroid hormone, is an aryl iodide. Thyroxine increase the rate of metabolism in cells throughout the body.*
*(A)*
Line 2: *What increases the rate of metabolism in cells throughout the body?
Options:
- (A) Thyroxine
- (B) Smoking
- (C) fever
- (D) bioaerosols
- (E) acetic acid
- (F) sweating
- (G) Power plants
- (H) heat produced*

Logic of a solution: *Plants that are adapted to very dry environments are called xerophytes. Bromeliads and cacti are xerophytes. Bromeliads and cacti have adapted to very dry environments.*
*(A)*
The original question: *Bromeliads and cacti have adapted to very _ environments.
Options:
- (A) dry
- (B) wet
- (C) arid
- (D) cold
- (E) UV
- (F) warm
- (G) humid
- (H) fern*

Line 1: *Mammals have a layer of fat under the skin to help insulate the body. If it has hair it is a mammal. An organism with hair has a layer of fat under the skin to help insulate the body.*
*(A)*
Line 2: *What does a hairy organism have under its skin to help insulate the body?
Options:
- (A) fat
- (B) hair
- (C) food
- (D) cell
- (E) nerves
- (F) coat
- (G) fur
- (H) marrow*

Logic of a solution: *Oxygen is essential for cellular respiration for all aerobic organisms. Oxygen, for example, is produced by plants. Plants are essential for cellular respiration for all aerobic organisms.*
*(F)*
The original question: *What is essential for cellular respiration for all aerobic organisms.
Options:
- (A) electron
- (B) glucose
- (C) Energy
- (D) Energy.
- (E) chemicals
- (F) Plants
- (G) fungi
- (H) bacteria*

Logic of a solution: *Behaviors can be learned through play. Kids imitate adult actions and behaviors. Actions can be learned through play.*
*(D)*
The original question:
*How can an animal learn actions?
Options:
- (A) movement
- (B) Chemical energy
- (C) by fighting
- (D) through play
- (E) by eating
- (F) when they sleep
- (G) stamina
- (H) Riding a bike*