Answer:
Growth factors
Explanation:
Growth factors, unlike hormone, have an influence on most cells on the body. They promote cell division and differentiation. Therefore, they are significant in promoting the cell cycle. Therefore, they should be able to be recognized by checkpoint proteins that regulate the cell cycle by either promoting progression or arresting the cell cycle.
They determine the north and south ends
Answer AND Explanation:
Gnetophytes are gymnosperms
, they are woody and the embryo has two cotyledons
. Cycads are woody plants that produce seeds found in Subtropical and warm temperate regions and also they produce motile sperm cells.
Survivorship curve = so, first of all, it's a curve, as in a graph.
It describes "survivorship" - the rate of survival, in other words: out of 100 organisms that are born, how many survive. This rate is different among species, for example, most humans live out to most of their life span, and almost all can survive well beyond a reproductive age.
However, in frogs for example, many many individuals are born, but only few can survive to adulthood: most die very young, before reproductive age.
So if you hear about a new species: let's say dogs, and you want to know how long they would live, you would look at their sirvivorship curve (and in some breeds of dogs, those that are likely not to be in shelters, but in homes, the survivorship curve would be similar as in humans: almost all individuals born can live long.