Answer: Antigens
Explanation: The ABO system of blood grouping is based on the basis of the type of antigens that are present in the red blood cells. Erythrocytes is another name for the red blood cells. Antigens are molecules that are capable of eliciting immune response. There are two types of antigens: antigen A and B. Blood type A has only antigen A, blood type B has only antigen B, blood type AB has both antigen A and B while blood type O has no antigen (neither A nor B antigen).
Similarly, Rh trait is determined by the presence or absence of rhesus antigen in the erythrocytes. Rhesus antigen is an antigen first discovered in rhesus monkey. Rh+ indicates the presence of rhesus antigen in the red blood cells while Rh- indicates the absence of rhesus antigen in the red blood cells.
<span>There are two types of stimulus that travel within our body. The two types are chemical and electrical. Electrical stimulus is the type of stimulus that travels from the motor neuron to the skeletal muscle. Electrical muscle stimulation is the elicitation of muscle contraction using electric impulses.</span>
<span>When you are pregnant, you do not ovulate because you have already fertilized an egg and it is embedded into the uterus where it is growing into a baby. The body knows this, so it does not shed the uterine lining. The shedding of this lining is triggered by hormones which change when the body is pregnant. During pregnancy, a large amount of progesterone is initially produced which helps to prevent the lining from shedding. If you are not pregnant, your progesterone level will begin to decline at the end of your cycle, triggering the shedding of the lining and the period. Birth control pills alter your hormones to mimic a pregnant state. This will prevent the body from releasing an egg and then shedding the uterine lining.</span>
Answer;
-Synovial cavity
Explanation;
-The synovial cavity/joint is filled with synovial fluid. A synovial joint contains a synovial cavity and dense, irregular connective tissue that forms the articular capsule normally associated with accessory ligaments.
-A synovial joint occurs at articulating bones to allow movement. It is distinguished by a surrounding synovial capsule.The bones of a synovial joint are surrounded by a synovial capsule, which secretes synovial fluid to lubricate and nourish the joint while acting as a shock absorber.