If two chromosomes of a species are the same length and haved similar centromere placements and yet are not homologous, what are they?

Non-homologous chromosomes

Explanation:

The overall length of the chromosomes and the placement of centromere are the two factors that required to same within the two pairs of chromosomes these chromosomes are considered as homologous chromosomes.  

The non-homologous chromosomes can be defined as chromosomes that do not have the same overall length and placement of centromere is also not same. These chromosomes do not belong to the same pair or do not appear in the same pair.

The time of replication and banding pattern varies considerably in the non-homologous chromosomes.

answer; /// i do believe its (heredity); good luck

when you breathe in, or inhale, your diaphragm contracts (tightens) and moves downward. this increases the space in your chest cavity, into which your lungs expand. the intercostal muscles between your ribs also enlarge the chest cavity. they contract to pull your rib cage both upward and outward when you inhale.