Answer:
Blood-brain barrier.
Explanation:
Blood brain barrier may be defined as the barrier between the blood capillaries and the component of the brain tissue. This blood brain barrier provide protection against the pathogens present in the blood.
The blood-brain barrier uses tight junctions that prevent the entry of microbes in the underlying tissue. The tight junctions allows only the entry of some selected particles and prevent the entry of other particles.
Thus, the correct option is (3).
A cross-sectional view of a log shows a concentric pattern. Which part of the stem gives rise to this pattern?
B. Xylem
as it contribute for most of a tree's growth in diameter.
Fungi are different from plants in that they are achlorophyllous.
<h3>Fungi vs plants</h3>
Fungi and plants are both eukaryotic in nature when it comes to their cells.
However, plants differ from fungi in that plants contain a green pigment known as chlorophyll while fungi do not. The green pigment enables plants to photosynthesize.
Thus, fungi are said to be achlorophyllous.
More on fungi and plants can be found here: brainly.com/question/1843408
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Answer:
Epigenetic effects can be caused by DNA heterochromatin and/or histone silence or activate.
As such, they can different chromosomes or certain chromosomal regions and be responsible for parental imprinting or influencing gene activity in oxidation and reduction.
Patterns of nucleotide demethylation and hypermethylation are often activate when cancer cells are compared to normal cells.
Explanation:
Cells acquire various patterns of gene expression during differentiation to adapt to a changing environment. Epigenetic and genetic alterations are considered as two independent mechanisms that participate in the onset and progression of cancer. Epigenetic mechanisms can be as important for biological events as genetic mechanisms, which do not imply a change in the DNA sequence, but do have an important role in the modification of gene expression.
DNA is the genetic composition of the cells in the human body, think of it as the coding for a computer but for cells. These carry your genetic composition (blue eyes, Brown hair, tall, short blah blah blah) and traits like smart, funny, shy.
Hope that helps.
