True because how else would we survive on Earth?
The answer for the question above is a sign stimulus.
Tibbergen used crude models of sticklebacks to investigate which features of male and female sticklebacks elicited attack and courtship behavior from male sticklebacks. The findings were that the male sticklebacks responded in a relatively invariant way and attacked a model with red belly.
Answer:
A
Explanation:
i meannnnnnnn they did select certain characteristics and did introduce/bred it to other plants
* The first statement is true.
Chromatid is a DNA molecule (the nucleofilament) associated with histone proteins and non-histone proteins. A chromatide has the shape of a rod that can have different degrees of condensation depending on the times of the cell cycle or the transcription activity of the genes.
This structural unit appears as a chromosome only during cellular divisions (mitosis or meiosis). The rest of the time, all chromatids form chromatin.
Each chromosome of a cell may consist of one or two chromatids depending on its state: just after a mitosis, or after the second meiotic division, each chromosome consists of only one chromatid, the rest of the time, after DNA replication, each chromosome consists of two completely identical chromatids, connected by the centromere, thus giving the two rods the shape of an X.
* The second statement is True
In its common definition the chromosome consists of one (or more) molecule of DNA, histones and non-histone proteins, disregarding its degree of condensation.
In its most scientifically rigorous definition, a chromosome is a fully condensed structure of chromatin. In this definition, the chromosome is only present during mitosis, more precisely during the metaphase where it takes the name metaphase chromosome (it is during the metaphase that it reaches its maximum degree of condensation).
Answer:
1:Axial skeleton,2:hemopoietic blood cell,
Explanation:
hope it help i only know two