19.3 Body Plans

Question 1

What is morphogenesis

Answer 1

The regulation of the pattern of anatomical development

Question 2

What are homeobox genes and what’s a homeobox

Answer 2

A group of genes which all contain a homeobox
A homeobox is a section of DNA 180 base pairs long coding for a part of the protein 60 amino acids long that is highly conserved in plants animals and fungi
This part of the protein binds to dna and switches genes on and off
They are regulatory genes

Question 3

What are hox genes

Answer 3

Group of homeobox genes only present in animals
Responsible for the correct positioning of body parts
They are found in gene clusters

Question 4

What is radial symmetry

Answer 4

No left or right sides only a top and bottom

Question 5

Why is mitosis essential in shaping organisms

Answer 5

It increases the number of cells leaving to growth

Question 6

Why is apoptosis essential in shaping organisms

Answer 6

It is programmed cell death
It removes unwanted cells and tissue
It can also release chemicals signals which stimulate mitosis leading to remodelling