A Typical Spiral Galaxy Has _____ Stars in a Disk

question 267

Multiple Choice

A typical spiral galaxy has _____ stars in a disk of diameter _____ ly.

• A) 10¹¹; 10⁵
• B) 10¹¹; 1000
• C) 10⁹; 10⁶
• D) 10⁶; 10⁵

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Definitions:

Monozygotic Twins

Monozygotic Twins are twins that develop from one zygote that splits and forms two embryos, also known as identical twins, sharing nearly 100% of their genetic material.

Dizygotic Twins

Also known as fraternal twins, are siblings born at the same time as a result of the fertilization of two different eggs by two different sperms.

Genes

Units of heredity made up of DNA that are responsible for the inherited characteristics in living organisms, dictating the development and functioning of organisms.

Selective Breeding

The process by which humans use animal and plant breeding techniques to selectively develop particular phenotypic traits by choosing which typically animal or plant males and females will sexually reproduce.