A.) Veins in the pulmonary circuit carry oxygen-rich blood
red blood cells are used to circulate oxygen through out the body, thus it is true.
Answer:
After 6000 years, approximately 500 atoms of carbon-14 will be left in the femur bone of an animal which had 1000 atoms of carbon-14 when the animal died.
Explanation:
The half-life of a radioactive isotope of an element is the time taken for half the atoms present in a given amount of the element to undergo decay or disintegration. For example, the half-life of carbon-14 isotope is 5730 years. This means that, if there are 100 atoms of carbon-14 present in a given sample of a material, in the next 5730 years, approximately, 50 atoms of carbon-14 will be left in the material.
Since the half-life of radioactive isotopes are constant, these radioactive isotopes are used in the determining the ages of ancient life-forms as well as rocks.
In the given example, after 6000 years, approximately 500 atoms of carbon-14 will be left in the femur bone of an animal which had 1000 atoms of carbon-14 when the animal died.
The lock an key analogy is used because each enzyme has specific substrates that fit into it. This is like how locks only work with a specific key. The enzyme is the lock and the substrates are the key.
2
This analogy is not perfect because there are often multiple substrates for each enzyme reaction. It only takes one key to turn the lock. The reaction is also taking place between the substrates themselves and not the enzyme. In the lock and key analogy, the lock is affected by the key, but in an enzyme reaction, the substrates are affected by the enzyme.
Hope I’ve helped ;)
Answer:
The correct answer will be option- synaptonemal complex.
Explanation:
The tetrad arrangement of the genetic material in an organism is mediated by a highly conserved structure known as the synaptonemal complex. The synaptonemal complex is formed during the prophase I of the meiosis I which attaches the chromatin of the homologous chromosomes.
The synaptonemal complex is a proteinaceous structure which is formed by the two lateral ladders like elements with a central portion composed of the central element. The chromatin gets attached to the lateral elements while the central a portion bridge space between the two ladders thus help in the formation of the tetrad.
Thus, option- synaptonemal complex is the correct answer.
