Double fertilization is a complex fertilization mechanism of flowering plants. This process involves the joining of a female gametophyte with two male gametes. It begins when a pollen grain adheres to the stigma of the carpel, the female reproductive structure of a flower.
Answer:
1. Head, neck, upper limb, thorax - super vena cava - top of the right atrium.
2. Lower limb - inferior vena cava - bottom of the right atrium.
Explanation:
The Heart pumps the oxygen-rich blood to the different parts of the body to Otake oxygen and nutrients to these organs and then takes the oxygen-poor blood returns from the body to the heart.
The two major vessels that return oxygen-poor blood to the heart are 1. superior vena cava (SVC) that drainages Head, neck, upper limb, thorax and terminate at top of the right atrium, and 2. inferior vena cava (IVC), Lower limb and terminate at bottom of the right atrium.
1. Head, neck, upper limb, thorax - super vena cava - top of the right atrium.
2. Lower limb - inferior vena cava - bottom of the right atrium.
These jobs are geneticists and criminologists! Geneticists study genes and how they're inherited, seeing where the DNA came from. Criminologists will supply the samples to the geneticists, as they take them from the crime scene.
Answer:
We mean that a cell changes to another type of cell.
Explanation:
<em>Stem cells </em>are a type of cell that has the potential to become a specialized cell, this change or differentiation, is possible thanks to the activation or deactivation of certain genes that promote (or inhibit) the expression of certain proteins that origins different types of cells (fmuscle cells, osteocytes, neurons). This differentiation happens when the cells receive cues internally ( through signals or contact between a group of cells and another or through transcription factors) or externally.
Then, a differentiated cell is a cell that had gone under the previously described process.
I hope this information is useful to you!
We have been able to see more of the cell in detail. We dont have to guess about things because we can see how it works. The more we see the more theories change because we know more.
