Although in humans there are 22 pairs of autosomal chromosomes, only three different chromosomal trisomies are commonly seen in newborns. of the remaining 19 autosomes, many trisomies have not been seen in newborns. why not?

The reason why only 3 out of the 22 possible autosomal trisomies are seen in newborns, is because the rest of them are chromosomal abnormalities not compatible with life and thus an spontaneous abortion occurs. The embryos suffering from these trisomies do not survive for more than a few weeks in the uterus, so the miscarriage often goes unnoticed for the mother as she may not have realized she was pregnant.

The only trisomies that are allow fetuses to be born are: Patau Syndrome (trisomy 13), Edwards Syndrome (trisomy 18), and Down Syndrome (trisomy 21). Out of these three, people with Down Syndrome have the largest life expectancy.

1. a host loses nutrients to a parasite

2. a parasite only benefits when the host is alive (cause if the host dies the parasite dies with it )

3. producers to consumers

4. the tapeworm is a parasite

5. they convert energy from the sun (photosynthesis)

6. sunflower-robin (i think im 80% sure)

7. producer

8. consumer

9. prey

10. fresh water snails ( cause the green algea is the producer and the snails are the primary consumers and the small fish consumer so is the big fish)

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.