2.  G1 cdk cyclin

3.  S cdk cyclin

4.  Transcription factor

1.  Fibroin

3.  Chitin

4.  Mucin

1.  trochophore

2.  tornare

4.  bipinnaria

1.  red blood corpuscles and while blood corpuscles occur in equal numbers

3.  white blood corpuscles are more in number than red blood corpuscles

4.  only red blood corpuscles occur

1.  Chelonea

3.  Equamata

4.  Rhyncocephalia

1.  elephant

2.  rhinoceros

4.  dinosaur

1.  A

2.  B

3.  C

2.  inbreeding

3.  crossing with homozygous

4.  hybridization

1.  one forms the food for the other

2.  they compete with each other in their growth

3.  the excreta of the forms the food for the other

1.  Bilateral symmetry

2.  Axiate organization

4.  Metamerism