Embryonic Development Gene Functions

The video explains how cell differentiation in embryos is regulated by a hierarchy of genes, including morphogens, egg polarity genes, gap genes, pair-rule genes, segment polarity genes, and Hox genes. Morphogens are molecules that create gradients to induce cell differentiation. Egg polarity genes establish the embryo's axes, while gap and pair-rule genes define segments. Segment polarity genes refine these segments, and Hox genes determine the identity of each segment. The video highlights the evolutionary conservation of these processes across species.

What is the primary purpose of regulatory hierarchies in embryonic development?

• To increase the size of the embryo

• To eliminate unnecessary genes

• To establish specific sequential patterns

• To create random patterns in organisms

How do morphogens influence cell differentiation?

• By changing the color of cells

• By spreading in a gradient and affecting cells based on concentration

• By increasing the temperature of the embryo

• By directly altering the DNA sequence

What is the role of egg polarity genes in embryonic development?

• To determine the embryo's anterior and posterior ends

• To increase the size of the egg

• To eliminate harmful cells

• To create a protective shell around the embryo

Which gene is deposited by the mother to mark the anterior end of the egg?

• Bitcoin

• Torso

• Tall

• Nanos

What is the function of gap genes in the regulatory hierarchy?

• To create a protective layer around the embryo

• To subdivide the embryo into rough subdivisions

• To eliminate unnecessary segments

• To increase the number of cells

How do pair-rule genes contribute to embryonic development?

• By eliminating harmful genes

• By establishing pairs of segments

• By creating a protective shell

• By increasing the size of the embryo

What is the role of segment polarity genes?

• To determine the size of the embryo

• To establish anterior and posterior ends for each segment

• To eliminate unnecessary cells

• To create a protective layer

What do Hox genes determine in an embryo?

• Which body parts each segment should develop into

• The color of the embryo

• The temperature of the embryo

• The size of the embryo

Why don't humans have the same limb arrangement as fruit flies, despite having similar Hox gene clusters?

• Because humans have more Hox genes

• Because fruit flies have a different number of segments

• Because Hox genes are not present in humans

• Because Hox genes affect different targets in different species

What is the evolutionary significance of Hox genes?

• They suggest a common ancestor between species

• They are unique to humans

• They are only found in fruit flies

• They are responsible for the size of the embryo