Answer: Anterior cruciate ligament
Explanation:The anterior cruciate ligament (ACL) connects the front of the tibia to the back of the femur. It keeps the tibia from sliding forward and limits its rotation. The posterior cruciate ligament (PCL) keeps the tibia from sliding backward. The patella ligament helps secure the patella over the front of the knee joint.
<h3><u>Answer</u>;</h3>
Key
A sorting device that is useful in classifying by observation is a <u>key</u>.
<h3><u>Explanation</u>;</h3>
- <em><u>Classification key or taxonomic key is a device that is used by scientists to identify unknown organisms. </u></em>
- They are constructed so that the user gets a series of choices about the characteristics of the unknown organisms.Thus, by making the correct choice at each step, one is led to the identity of the specimen.
- Therefore<u><em>, keys can be used to identify a living organism or determine which group it belongs to</em></u> by answering questions on the key about characteristics of living things.
Answer:
c. secondary consumer level
Explanation:
Most secondary extinctions are due to direct bottom‐up effects: consumers go extinct when their resources are lost. Secondary extinctions due to trophic cascades and disruption of predator‐mediated coexistence also occur.
Answer: Epidemiology
Explanation:
Epidemiology is a branch of medicine, the study of human health and disease at the population level. Epidemiology deals with the incidence, distribution, prevalence and possible control of diseases and other factors relating to health. By tracking the cause and distribution of the disease among many individuals of the population, epidemiologist can identify potential stategies for the preventing and controlling of diseases and disorders.
Stem cell therapies are not new. Doctors have been performing bone marrow stem cell transplants for decades. But when scientists learned how to remove stem cells from human embryos in 1998, both excitement and controversy ensued.
The excitement was due to the huge potential these cells have in curing human disease. The controversy centered on the moral implications of destroying human embryos. Political leaders began to debate over how to regulate and fund research involving human embryonic stem (hES) cells.
Newer breakthroughs may bring this debate to an end. In 2006 scientists learned how to stimulate a patient's own cells to behave like embryonic stem cells. These cells are reducing the need for human embryos in research and opening up exciting new possibilities for stem cell therapies.
