Answer:White blood cells, also called leukocytes or leucocytes, are the cells of the immune system that are involved in protecting the body against both infectious disease and foreign invaders. All white blood cells are produced and derived from multipotent cells in the bone marrow known as hematopoietic stem cells. Leukocytes are found throughout the body, including the blood and lymphatic system.
Explanation:
Answer: The lock-and-key mechanism is usually associated with the complementary shapes of an enzyme with a single substrate wherein the lock that is being referred to is the enzyme and the substrate is the key. One right sized substrate (key) fits into the active site (key hole) of the enzyme (lock).
Answer:
C. their gametes do not require water for fertilization to occur.
Explanation:
Seed bearing plants are plants that produce seeds. The gametes of seed-bearing plants do no depend on water for fertilization. Fertilization could occur through the transfer of pollen from the male gametophtye to the female gametophyte through animals or wind.
Unlike other plant types like the bryophytes, they rely on water for fertilization. They so have xylem and phloem as well as other plants. They also have stems,roots and leaves like other plants.
Answer:
The answer is D.
Explanation:
The way x-rays are produced is as follows; using a vacuum environment in a tube, the cathode is heated to a degree where it releases electrons, then these electrons collide with the anode releasing energy that create the x-rays.
All of the options are correct. Although the electron most likely won't stop, it will slow down and change direction after the collision. The law of conservation of energy is also applied in this situation, meaning that the kinetic energy of the electron released by the cathode will transfer to the anode to produce the x-rays. Most of the energy after the collision is converted into heat, which is why the metal used as the anode can heat up to 2000 degrees celcius.
I hope this answer helps.
