Answer:
Human sex cells are produced by a two-part cell division process called meiosis.
Explanation:
Through a sequence of steps, the replicated genetic material in a parent cell is distributed among four daughter cells. Meiosis produces gametes with one-half the number of chromosomes as the parent cell
In semiconservative DNA replication, each new double helix that will form will have 1 polynucleotide strand that is from the old DNA molecule and is an Old or Parent strand, and will have a polynucleotide strand from the newly synthesized one, the new DNA strand.
Answer: d. Extracellular matrix was discovered more than 20 years ago.
Explanation:
According to biological sciences, the extracellular matrix is a matrix that consists of three dimensional network of extracellular macromolecules such as enzymes, collagen and glycoproteins which provide structural and biological support for surrounding cells as well.
It is found that it is discovered over 20 years ago in the matrix formed in the mouse EHS sarcoma. Therefore, correct answer is (d).
The correct answer is: D) Binding of the neurotransmitter causes chemically gated sodium channels to open in the motor end plate (junctional folds of the sarcolemma) and sodium enters the cell.
The motor neuron cell is connected to muscle cell via synaptic cleft, where neurotransmitter is released. The muscle side of this synapse is called motor end plate. Released neurotransmitter is acetylcholine and it binds to its receptor (ACh receptor) on the motor end plate. As it binds, ion channels open, and Na+ gets into the muscle cell. This event reduces the voltage difference between the inside and outside of the cell and causes depolarization which creates a wave through the entire muscle cell (its membrane-sarcolema). As a consequence, Ca2+ is released from the sarcoplasmic reticulum which will cause the contraction of the muscle cell.
The answer is; cancer occurs due to unregulated cell division
This causes them to proliferate causing a mass of cells and affect neighboring tissues. The cells are usually undifferentiated and therefore do not function properly as tissue. This unregulated division is due to malfunction of the tumor suppressor gene that is significant in cell cycle regulation and apoptosis.
