Answer:
a. The maternal copy of UBE3A is expressed and the paternal copy is silenced.
Explanation:
When UBE3A chromosome is in neurons, paternal allele is silent and maternal allele is expressed in process of genomic imprinting. In some cases UBE3A is expressed from both paternal and maternal chromosomes. The paternal chromosome is blue whereas maternal chromosome is magenta.
Answer:
Endosteum plays an important role in bone repair, bone remodelling and appositional bone growth.
Explanation:
Endosteum consists of a soft and thin connective tissue that lines the cavity of femur and humerus. Some of the major functions of endosteum are as follows:
Bone remodelling: Endosteum can stimulate the bone resorption that leads to the formation of new bone from the outside.
Bone repair: Hematoma, at the time of bone injury causes the division of endosteal cells and helps in bone repair.
Appositional bone growth: Endosteum that line the osteoblast cell can secrete bone matrix and increases the bone diameter.
ANSWER: A. The sun is located at the centre of the universe
To test for the keystone species hypothesis, the wolves in another region can be removed or trees can be reintroduced to see the effect on the ecosystem.
<h3>What is a keystone species?</h3>
A keystone species is an organism whose existence defines an entire ecosystem such that them, the ecosystem would be severely affected or may not exist.
Trophic cascades are events which result in serious distortions in an ecosystem as a result of the removal or addition of a top predator.
To test for the hypothesis of keystone species and trophic cascades, the wolves in another region can be removed or trees can be reintroduced to see the effect on the ecosystem.
Learn more about keystone species at: brainly.com/question/2044051
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