Crayfish are invertebrates which means they don't have a backbone. They are also arthropods, which means that they have a protective exoskeleton on the outside of their body. Other arthropods include insects, spiders, and centipedes. Crayfish continually shed their exoskeleton and regrow a new one. During this transition is when they are most vulnerable to predators because they aren't protected by their outer shell.
Crayfish are found all over the world in many different freshwater environments, such as rivers, creeks, springs, and swamps. But this doesn't necessarily mean that you will be able to find them. They are somewhat cryptic because they dig out homes for themselves under rocks and blend in well with their environment. Crayfish will ardently defend this dwelling against intruders using their strong front claws
Answer:
1.ans Phylogenetic Trees
Scientists use a tool called a phylogenetic tree to show the evolutionary pathways and connections among organisms. A phylogenetic tree is a diagram used to reflect evolutionary relationships among organisms or groups of organisms.
2.ans Binomial Nomenclature Rules
The entire two-part name must be written in italics (or underlined when handwritten). The genus name is always written first. The genus name must be capitalized. The specific epithet is never capitalized
3.ans Dichotomous Key
A dichotomous key is a tool created by scientists to help scientists and laypeople identify objects and organisms. Typically, a dichotomous key for identifying a particular type of object consists of a specific series of questions.
Answer:
negative feedback loop involving insulin and glucagon help to keep blood glucose levels within a narrow concentration range. If glucose levels get too high, the body releases insulin into the bloodstream.
hope it help
I belive its C
Explatatiom burning something is chemical and melting something is physical.