T killer cell or Cytotoxic T cells are the cells in animals that are used to destroy bacteria and viruses after combining with lysosomes.
<u>Explanation</u>:
The T cells kills the bacteria and virus. The T cells can easily identify the pathogen when combined with the lysosomes. The activated T cells releases a material called perforin. This substance gets into the walls of the affected cell and punctures its walls. Due to hole in the walls, there happens discharge of fluid and electrolytes, which leads to the death of the cell. The substance secreted is the cytolytic proteins from the lysosome which helps in destruction of the infected cells.
The awnser to this question would be B.
Answer:
Risk factors include: Advancing maternal age. A woman's chances of giving birth to a child with Down syndrome increase with age because older eggs have a greater risk of improper chromosome division. A woman's risk of conceiving a child with Down syndrome increases after 35 years of age.
Answer:
They changed their shape.
Explanation:
The aliens changed their shape because their shapes makes the people frightened. Their shape structure is different from the humans so they change their shape in order to walk among people easily and interact with people which they can't do with their real body structure. So that's why they changed their shape when they interact with people or to walk among people.