Embryonic development involves process of formation and development of an embryo. In humans, during the early stages, 10 weeks of embryonic development, all the major body organs are formed.
<span>What did Jean-Baptiste Lamarck believe about traits such as large muscles that are acquired during one's lifetime?
</span><span>They can be passed on to offspring.
</span>
<span>Jean-Baptiste Lamarck proposed that organisms have an innate tendency toward complexity and perfection.</span>