One Week After Conception, a Ball of 100 Cells Becomes

question 42

Multiple Choice

One week after conception, a ball of 100 cells becomes firmly embedded in the lining of the uterus in the process of implantation. This ball of cells is called the

• A) zygote.
• B) prenatal period.
• C) fetus.
• D) embryo.
• E) blastocyst.

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Definitions:

Lymphocyte Activation

The process by which lymphocytes (a type of white blood cell) are stimulated to respond to pathogens or other antigens.

Antigen-presenting Cells

Specialized immune cells that capture antigens and present them on their surface to T-cells, initiating an immune response.

Helper T Cells

White blood cells that play a critical role in the immune system by activating other immune cells to fight off infections.

Cytokines

Small proteins released by cells that have a specific effect on the interactions and communications between cells, often involved in immune responses.