Which of the following statements correctly describes a difference between bacterial cells and animal cells? A. Animal cells contain cytoskeletons. Bacterial cells do not.

B. Animal cells contain ribosomes. Bacterial cells do not

C. Animal cells have a membrane surrounding their nucleus. Bacterial cells do not have membrane surrounding the nucleus.

D. Animal cells are surrounded by a cell wall. Bacterial cells are not

Which is an advantage of having memory cells when a pathogen is encountered for a second time. a) the memory cells are what proliferate into clones of cells in response to the binding of an antigen. b) memory cells are vital to the primary immune response in that they immediately recognize pathogens even at the first encounter. c) memory cells are essentially effector cells that are short lived and attack antigens even without having a receptor specific to that antigen. d) it ensures that more lymphocytes with a receptor specific to a particular antigen will be present than in a host that had never encountered that pathogen.

Sara goes on a slingshot ride in an amusement park. she is strapped into a spherical ball that has a radius 3*10^2 of centimeters. what is the volume of air in the spherical ball? use this formula: volume of a sphere=4/3pi,r^3 , where r is the sphere’s radius.

Why was mendel's work not accepted at the time? o a. his results were false. o b. he did not repeat his experiments. o c. he did not have any data. o d. his results were surprising,