The patellar reflex can be defined as the kicking movement of the lower leg which occurs with a sudden twitch when the patellar tendon of a person is tapped. This patellar tendon is present below a person's kneecap. This reflex happens only when the leg is bended. It is impossible for patellar reflex to occur if the leg is straight as the quadriceps muscles are already contracted and a sudden kicking movement of the leg in such state could not be elicited. The patellar reflex protects the quadriceps from stretching too much.
Answer:Each and every one of us have several roles. Organisms in a community play other roles too. An organism's role within an ecosystem depends on how it earn its nutrients. Organisms collect their nutrients in very different actions, so they have different roles in an ecosystem.
Explanation:
The food chain describes who eats whom in the wild. Every living thing—from one-celled algae to giant blue whales—needs food to survive. Each food chain is a possible pathway that energy and nutrients can follow through the ecosystem.
For example, grass produces its own food from sunlight. A rabbit eats the grass. A fox eats the rabbit. When the fox dies, bacteria break down its body, returning it to the soil where it provides nutrients for plants like grass.
Of course, many different animals eat grass, and rabbits can eat other plants besides grass. Foxes, in turn, can eat many types of animals and plants. Each of these living things can be a part of multiple food chains. All of the interconnected and overlapping food chains in an ecosystem make up a food web.
Answer: This answer is for all the questions: Chargaff's rules state that DNA from any species of any organism should have a 1:1 stoichiometric ratio of purine and pyrimidine bases (i.e., A+G=T+C) and, more specifically, that the amount of guanine should be equal to cytosine and the amount of adenine should be equal to thymine.
Explanation:
The
patellar reflex is the most common example or a spinal reflex. When the knee is
tapped, the nerve that will receives this stimulus sends an impulse to the
spinal cord and relay it to the motor nerve. This sources the quadriceps muscle
at the front of the thigh to contract and twitch up the leg. This reflex contains
simply two nerves and one synapse. The leg will start to twitch up on the other
hand the brain is just suitable aware of the tap and comprehends the situation.
<span>Subsequently the tap, the leg is routinely lengthy
once and comes to rest. The nonappearance of this reflex is problematical and recognized
as westphals sign this reflex might be lessened or absent in lower motor
neuron lesions and during sleep. </span>
