Answer:
body size
more
circulatory system
egg deposition
Explanation:
Because of their large <em>body size</em> , ancestral amphibians likely faced challenges supporting themselves out of the aquatic environment.
Although there was far <em>more</em> oxygen available to gills in air than in water, the delicate structure of gills couldn't be supported in the terrestrial environment.
The costs of locomotion on land and greater oxygen demand from enlarged muscles led to modifications of the heart and <em>circulatory system</em>
These early amphibians could not venture too far away from water because <em>egg deposition</em> was restricted to moist environments.
A recessive trait is observed when an organism has 2 recessive genetic factors.
Answer:
Explanation:Simply put: A period is when a woman's body releases tissue it no longer needs. ... Every month or so, the uterus lining gets thicker to prepare for a fertilized egg if the woman becomes pregnant. If the egg doesn't get fertilized, that lining is released from the body as blood through the vagina.
Period pain is common and a normal part of your menstrual cycle. Most women get it at some point in their lives. It's usually felt as painful muscle cramps in the tummy, which can spread to the back and thighs. The pain sometimes comes in intense spasms, while at other times it may be dull but more constant.