Answer:
A.
Explanation:
It shows a clear view of what a group of cells of a plant would be like.
Answer:
The correct answer is- Immune system
Explanation:
There are physical, chemical and immunological barriers present in our body which helps us to protect from the foreign antigen. They all assist each other and helps in pathogen removal from our body.
The physical barrier includes skin, gastrointestinal tract, respiratory tract, etc which do not allow the microbe to enter the body. Chemical barriers include tear, saliva, acid in the stomach which kills microbes on the body surface.
Immune cells like macrophages, B cells kills microbes when it gets in the body. Lymphatic system also contain immune cells and helps in microbe removal.
So the immune system is assisted by physical barrier, chemical barrier, and lymphatic system.
Answer:
Cytoskeletal elements play important roles in cell division. The mitotic spindle apparatus is made of "microtubules" and pulls sister chromatids apart, whereas the contractile ring is made of "actin filaments" and required for the separation of daughter cells at the end of the mitotic phase of the cell cycle.
Explanation:
The three chief organizational apparatuses of the cytoskeleton are microtubules (formed by tubulins), microfilaments (formed by actins) and intermediate filaments. All three apparatuses cooperate with each other non-covalently. The cytoskeleton is composed of protein filaments and is found throughout the inside of a eukaryotic cell. The cytosol is the main component of the cytoplasm, the fluid that fills the inside of the cell. The cytoplasm is everything in the cell except for the cytoskeleton and membrane-bound organelles.
Answer:
b. They are produced by memory B cells
Explanation:
The rapid cell division in activated B cells is followed by the differentiation of daughter cells into the plasma cells. The plasma cells are the precursor for antibodies and memory B cells. The antibodies kill the antigens while memory B cells are long-lived cells.
Hence, antibodies are not produced by memory B cells but by plasma cells.
