<span>The mineral crystals in obsidian are too small to see without a microscope. This is because the rock cools so rapidly from magma that crystals barely have time to form. Obsidian is a normally happening volcanic glass framed as an extrusive molten shake. It is delivered when felsic magma expelled from a well of lava cools quickly with negligible precious stone development.</span>
Age, Diet, lifestyle choices, environment and RES
Answer:
The correct answer is A) Histone deacetylation generally decreases gene expression.
Explanation:
Histones are the proteins that are responsible for the condensation of chromatin, which is directly linked to the capacity that a gene has to be expressed. The more condensed a gene is, the less expressible it becomes.
In order to regulate the gene expression, histones can suffer from many modifications that can change their conformation and the expressiveness of specific genes.
<u>Histone acetylation is linked with an increase of gene expression; while deacetylation and methylation decrease gene expression.</u>
Answer:
The options are not given but they are gotten from another websites.
A. Capillaries surrounding the brain have no pores and are surrounded by membranes of astrocyte cells.
B. Capillaries surrounding the brain have pores and are surrounded by membranes of astrocyte cells.
C. Capillaries surrounding the brain have no pores and are not surrounded by membranes of astrocyte cells.
D. Capillaries surrounding the brain have pores and are not surrounded by membranes of astrocyte cells.
The correct answer is option A.
Capillaries surrounding the brain have no pores and are surrounded by membranes of astrocyte cells.
Explanation:
Capillaries surrounding the brain have no pores and are surrounded by membranes of astrocyte cells because
Capillaries are tiny blood vessels in the circulatory system that connect aterioles to venules. They are the most abundant or they are much blood vessels. They can penetrate the tissues of the body which allow passage of food nutrients, oxygen in the body thereby allowing exchange of nutrients and oxygen between the body tissues and the blood.
Capillaries surrounding the brain have no pores and are surrounded by membranes of astrocyte cells while capillaries in the periphery Capillaries surrounding the brain have pores and are not surrounded by membranes of astrocyte cells.
