After fertilization occurs, the cells of the wedge move towards the middle. This process is called __________.

When the cells of a developing embryo bunch toward the middle, they form a concentration of cells called the ___________.

An infertile egg can be distinguished by the presence of __________.

those who study embryology do not agree on the number of cells present at this point, but estimates range from about ____________ cells

Leg buds on a developing embryo are created by cells between _____ and _____ days.

Which of the following somites will form into skin during embryonic development?

The yolk particles contain ___________ as the major energy source, as well as some of the protein and other nutrients needed by the developing embryo.

The head of an embryo should be tucked under the __________ wing and located toward the __________ end of the egg before hatch.

All parts of the chick are in place by what day of incubation?

The inner part of the blastoderm is known as the ____________ - meaning that light can pass through it to give an almost transparent appearance.

During cell division of a developing chicken embryo, all of the following are layers that the cell forms into except:

During early embryonic development, after ____ hours of incubation, blood vessels coming from the embryo join with those coming from the area opaca.

The cells that lay on the inside of a developing embryo at 18 to 19 hours of incubation are called __________.

During incubation, what membrane forms under the embryo and collects water from the albumen?

The _____________ is the part of the blastoderm from which the embryo develops and cell division starts from the back and moves forward.