The correct answer is the insertion.
<span>Insertion is the attachment site of the muscle end that does move when the muscle contracts. On the other hand, the origin is the attachment site that does not move during contraction (end of the muscle is fixed).</span>
Ionic bonds involve the gaining and losing of valence electrons between atoms, while covalent bonds involve the sharing of valence electrons between atoms
Answer:
All of these choices are correct.
Explanation:
Cell cycle is the process of growth and division of cell. It comprises of interphase and mitosis. In interphase the cell grows, replicates its genomic content and prepares itself for division. In mitosis the division occurs.
Cell cycle is controlled by a group of kinases called as Cyclin dependent Kinases (CDKs). They act by phosphorylating their substrates. They are of various types like Cdk1, Cdk2, Cdk4 etc. They become active when they bind to a regulatory protein called cyclin. They are also of various types like Cyclin A, Cyclin B, Cyclin C etc. Level of cyclin and corresponding CDK increases and decreases according to the stage of cell cycle. For example in S phase of cell cycle concentration of cyclin A and E shoots up. CDK2 is able to bind to these cyclin molecules and hence it becomes active.
Cell cycle has major checkpoints where the condition of cell is analysed before it proceeds to the next stage of cycle. If any abnormality is detected, repair mechanism is activated or the cell is killed. Checkpoints do not allow cell cycle to proceed in damaged cells.
p53 is a tumor suppressor protein which can halt cell cycle when it detects some abnormality in cell. It usually acts in G1/S checkpoint (before the DNA replication starts in cell) and G2/M checkpoint (before the cell division begins). Hence, all of the above statements are true.
Answer:
The correct answer would be A. crust.
The crust is the outermost layer of the earth which is composed of different types of rocks such as sedimentary, metamorphic, and igneous rocks.
It is completely solid and can be broadly classified into two types: continental crust and oceanic crust.
The thickness of the oceanic crust is about 5 km to 10 km. It is primarily composed of basalt, gabbro, and diabase.
The thickness of the continental crust is around 30 km to 50 km.
The crust forms lithosphere along with hard and upper mantle.
