Civil Superior Services — Complete MCQ Bank
CSS is Pakistan’s premier federal competitive examination. Strong preparation requires conceptual clarity, broad general knowledge and consistent practice across compulsory and optional areas.
Which process by which bacteria take up free DNA from their environment was discovered by Griffith?
Which type of white blood cell produces specific antibodies against antigens?
Which plant hormone signals guard cells to close stomata during drought conditions?
What is the role of helper T cells in coordinating the immune response?
Which layer of the skin contains melanocytes that produce the pigment responsible for skin colour?
Which process converts excess amino acids into urea in the liver for kidney excretion?
Which organelle within the nucleus is responsible for producing ribosomal RNA?
Which chromosomal disorder is caused by the presence of an extra chromosome 21?
What is the term for the complete set of chromosomes in a cell of an organism?
Which type of RNA brings amino acids to the ribosome during protein synthesis?