1. Los tipos de sangre estan determinados por la presencia de proteinas
localizadas en
a. En todas las celulas sanguineas.
b. Solamente en globulos blancos
c. Solamente en celulas T
ayudantes d. Solamente en los
globulos rojos.

after receiving a stimus, the sensory receptors send(s) signals to the appropriate area of the body.  

the must be sensory neurons.  

hope its .

the level of progesterone is low at the pre-ovulatory phase of the cycle but it gradually increases and the levels are high at the luteal phase. if pregnancy occurs, the level of progesterone will be high throughout the pregnancy.

if egg is fertilized and the mother gets pregnant, progesterone starts preparing the uterus for the implantation. it starts building up the lining of uterus and make it hostile of the period of pregnancy.