The embryos were then transferred to recipient women. They had pregnancies when the recipient's cycle was from 4 days in front of to 3 days behind the donor's uterus at ovulation. This suggests a window of implantation of up to 7 days. Navot et al, in 1991 reported on donor embryo transfers done with 2-3 day old embryos on recipient cycle days 15-20 (artificial cycles controlled with meds).
Making the world better, one answer at a time. Catalysts are never consumed in the reaction. that's what makes them catalyst! not a reactant. they increase the rate of reaction by lowering the activation energy for the reaction. One of the ways to do this by providing an alternative route for the reaction to follow.
The Role Catalysts In Chemical Reactions, Their Importance In Industry, Problems and New Developments. OXFORD AND CAMBRIDGE SCHOOLS EXAMINATION BOARD. General Certificate Examination - Advanced Level Chemistry (Salters') - Paper 3 mock. ROBERT TAYLOR U6JW. A Catalyst is a substance that alters the rate of a reaction. The catalyst remains unchanged at the end of the reaction. The process is called catalysis. In this report I aim going to explain the role of catalysts in chemical reactions and their importance in industry.