In 8 days, the zebrafish Max develops from a single cell to a hatched larva. [1] On day 1, Max is a young embryo in stage 20 with visible chorion, cytoplasm, and oil globule. [2] By day 3, Max is in stage 26 with a heartbeat of 110 BPM and visible eyes and fluids flowing. [3] By day 8, Max has hatched from the egg with a visible head, tail, fins, and many spots on its back.

1. About 8 Days in the
Life of Max
By Liz Keller

2. Filaments, Oil
Globule, Cytoplasm,
& Chorion
Day 1
Today, I was taken out of my dish
and put on a microscope. The light
was really bright! I am in about
stage 20 and still a youngster. My
egg appears whitish and everything
is hard to see.

3. Day 2 Somites
Today I have a heartbeat of 160
beats per minute!! I am in stage
23 and the somites are visible.
My parents can see a better
image of me.

4. Day 3
Today I am in stage 26. I have a
heartbeat of 110 BPM. Fluids are
now flowing through me and my
eyes are clearly visible.

5. Max’s Heartbeat (Day 3)

6. Spleen,Vitalline Membrane, Liver,
Blood Vessel, Intestine, Swim
Bladder, Urinary Bladder, & Heart
Day 4
Today my heartbeat is 140 BPM.
Any day now, I should have pink
blood flowing through my egg. I
am in stage 30 today. My urinary
bladder is visible today as well as
other organs!

7. Yolk Sac
Day 5
Today my heart rate decreased
to 136 BPM for an unknown
reason. I am in stage 31 and my
tail is definitely identifiable. My
yolk sac is also found.

8. Day 6
Today, I have red blood in my
egg. My heart rate decreased
again to 126 BPM and my
pectoral fin is visible. I am able
to move it! I am in stage 32.

9. Day 7
I am getting so crowded in my
egg at this point! I have barely
any space left and my heart rate
is still 120. I’m in stage 33. I will
soon hatch!!

10. Optic cup, Brain, Mouth, Dorsal
Fin, Pectoral Fin
Day 8: Hatching
I hatched today! It feels great to
be able to finally move around. I
have many spots on my back,
too.

11. Head

12. Tail

13. Fin

15. The End!!