How does pregnancy begin? A. A placenta forms in the uterus.
B. Contractions begin in the uterine wall.
C. A sperm reaches an egg in the fallopian tube.
D. The blastocyst differentiates into two cell types.

The idea that all living things are made up of cells is considered scientific law. this means the idea is an emerging scientific idea that has a logical explanation. has been tested with similar results at least twice. is supported by scientific consensus and a large amount of evidence. has been rejected only once by the scientific community

Which of the following is a limitation of a clinical trial? a.)amount of random assignments b.)hospital cost c.)number of test tubes d.)amount of peer review

2. cheryl hears a new song on the radio every day during the week on her commute to work. surprisingly, when the song comes on at a party on saturday night, she knows most of the words without trying. describe the three ways that we use cognition to learn without reinforcement. which type of cognitive learning without reinforcement best explains how cheryl knew the song lyrics? explain your answer.