What is the first step of pregnancy?

A. Differentiation of blastocyst

B. Contraction of a uterus

C. Development of placenta

D. Formation of a zygote

Darwin hypothesized that new species could appear gradually through small changes in an ancestral species. What experiment did he conduct to test this hypothesis? Answer Choices: A. the breeding of finches B. the breeding of pigeons C.

An ecological pyramid is sometimes used to show both the flow of matter and energy in an ecosystem. The pyramid narrows as matter and energy flow from the bottom to the top.

Which is an example of a biotic factor

Which organisms convert nitrogen into a form that is usable by humans

What are seismic waves? What is their relationship to earthquakes?

Disease caused by bacteria often found in dirt that release toxins that cause muscle spasms:

Cross-contamination is the transfer of harmful organisms from one food item to another. true false

What type of consumers are humans?

Which response occurs because of the auxin a. A flower blooms b. A fruit ripens c. A plant leans toward a light source d. A seed germinates

For positioning purposes, in the average adult skull, the difference between the OML and the IOML is approximately (select one): a. 5 degrees b. 7 degrees c. 10 degrees d. 12 degrees