Answer:
gills
Explanation:
They need the gills since they are first born underwater and live part of their life down there. They don't grow tails, legs, or lungs until later on
Ex: tadpoles
Ecological relationships describe the interactions between and among organisms within their environment. The can be positive, negative or neutral.
Predation can be considered as any interaction between two species where one species is a bit stronger and benefits by obtaining resources from and to the detriment of the other.
Competition occurs when multiple organisms compete for a limited resource that they all need to survive.
Mutualism is a positive interaction that benefits two different species in the community. For example, the mutualistic relationship between alga and fungus that form lichens creating a new beneficial species in the community.
Commensalism is an interaction where one species benefits and the other remains unaffected.
Amensalism is an interaction in which the presence of one species has a negative effect on another, but the first species is unaffected. This could occur as simply as a human walking across a lawn, crushing the lowest level of the community.
Answer: The main function of the pineal gland is to receive information about the state of the light-dark cycle from the environment and convey this information to produce and secrete the hormone melatonin.
Explanation:
Answer:
sex chromosomes have X and Y chromosomes whereas sexual reproduction is a type of reproduction.
Explanation:
Two sex chromosomes are present in humans and most other mammals i.e. the X and the Y chromosomes. Females have two X chromosomes in their egg cells, whereas males have both X and a Y chromosomes in their sperm cells while on the other hand, reproductive sex means sexual reproduction in which sperm of male fuse with eggs of female organism forming zygote that turns into a fertile offspring.