Answer the following question given this paragraph: 18.4 Leukocytes and Platelets Leukocytes function in body defenses. They squeeze out of the walls of blood vessels through emigration or diapedesis, then may move through tissue fluid or become attached to various organs where they fight against pathogenic organisms, diseased cells, or other threats to health. Granular leukocytes, which include neutrophils, eosinophils, and basophils, originate with myeloid stem cells, as do the agranular monocytes. The other agranular leukocytes, NK cells, B cells, and T cells, arise from the lymphoid stem cell line. The most abundant leukocytes are the neutrophils, which are first responders to infections, especially with bacteria. About 2030 percent of all leukocytes are lymphocytes, which are critical to the body's defense against specific threats. Leukemia and lymphoma are malignancies involving leukocytes. Platelets are fragments of cells known as megakaryocytes that dwell within the bone marrow. While many platelets are stored in the spleen, others enter the circulation and are essential for hemostasis; they also produce several growth factors important for repair and healing. Q: Which leukocytes are first to respond to bacterial infections? Choices: - chemocytes - erythrocytes - microcytes - neutrophils A:
neutrophils
(Question)
Answer the following question given this paragraph: Gene cloning is making an exact copy of a gene. Q: What artificial process involves making an exact copy of a gene? Choices: - material cloning - candidate cloning - ribosome cloning - gene cloning A:
(Answer)
gene cloning
Ques: Answer the following question given this paragraph: Base units have independent scales and cannot be described by a combination of any other base units. Examples of base units used in chemistry are length, mass, temperature, and time. Q: Time, mass, length, and temperature are considered to be what kinds of units? Choices: - support - measurement - unitary - base A:
Ans: base
(Q).
Answer the following question given this paragraph: Small molecules can pass through the plasma membrane through a process called diffusion. Diffusion is the movement of molecules from an area where there is a higher concentration (larger amount) of the substance to an area where there is a lower concentration (lower amount) of the substance ( Figure below ). The amount of a substance in relation to the total volume is the concentration . During diffusion, molecules are said to flow down their concentration gradient , flowing from an area of high concentration to an area of low concentration. Molecules flowing down a concentration gradient is a natural process and does not require energy. Q: What is the process of small molecules passing through the plasma membrane called? Choices: - permeation - absorption - convection - diffusion A:
(A).
diffusion
Ques:Answer the following question given this paragraph: All eukaryotic cells have a nucleus and other organelles. Each organelle has a special job to do. Q: Along with other organelles, all eukaryotic cells possess what structure? Choices: - chromosomes - cell walls - flagella - nucleus A:

Ans:nucleus
Answer the following question given this paragraph: Meningitis is an infection of the membranes that cover the brain and spinal cord. If you have meningitis, you are likely to have a fever and a headache. Another telltale symptom is a stiff neck. Meningitis can be caused by viruses or bacteria. Viral meningitis often clears up on its own after a few days. Bacterial meningitis is much more serious ( Figure below ). It may cause brain damage and death. People with bacterial meningitis need emergency medical treatment. They are usually given antibiotics to kill the bacteria. Q: Meningitis is an infection of the membranes that cover the brain and what else? Choices: - umbilical cord - notochord - liver - spinal cord A:
spinal cord