Answer: Glial cells called ASTROCYTES help maintain the blood-brain barrier, whereas SCHWANN CELLS create the myelin that envelopes axons
Explanation: Glial cells are specialized cell that are found in both central and peripheral nervous systems, that surrounds the neurones, providing them with support and insulation. There are different types of Glial cells these includes:
- Astrocytes: they maintain the blood brain barrier.
- Schwann cells: create the myelin that envelopes axons of the peripheral nervous system neurones.
- satellite cells: These cells help regulate the external chemical environment of neurones.
- Microglia: they clean up cellular debris through phagocytosis.
- Oligodendrocytes: create the myelin that envelopes axons of the central nervous system
The question is incomplete and the complete question is
Suppose that ear length in rabbits is controlled by two additive genes, each of which has two alleles. A true-breeding female (aabb) with 6-cm ears is mated to a true-breeding male (AABB) with 16-cm ears.
Answer:
AABb or AaBB
Explanation:
We know that,
aabb genotype - 6 cm
AABB genotype- 16-cm
To calculate the length of earlobe contributed by each allele in a genotype is :
1. length of aabb/4 or 6/4= 1.5 cm (a and b contribute for 1.5 cm each)
2. Length of AABB/4 or 16/4= 4 cm (A and B contribute for 4 cm each)
Now to have the earlobe to be 13.5 cm long then the genotype must be
13.5 = 4+4+4+1.5 or A+A+B+b or A+a+B+B
Therefore, the genotype will be-either AABb or AaBB
Nonrenewable resources and found it fixed amount hence not managing properly will lead to full use of it and cannot be replaced
Explanation:
- Nonrenewable resources are found in the ground and they are the natural resources created by nature
- It includes fossil fuels, like natural gases, oil, coal, etc and also the minerals used for making metals
- These natural resources have taken more than human's life span to form, up to million years. Hence, replacing of these natural resources are not possible
- Renewable natural resources are trees, water, air. These resources can be recycled and they are also circulating in the atmosphere in the form of a cycle.
- Hence, nonrenewable resources should be managed properly for it last for the coming generations.
Answer: Senescent cells
The Senescence of
the eyes is often demonstrated by the presence of <span>senescence cells. They are forms of cells that are normally capable of
replication within mammalian tissues but permanently non-dividing and
share features with oncogene-induced senescence.
</span>Moreover, the accumulation of senescent cells has been overwhelmingly
studied using fibroblasts and has been proposed to act as an ageing mechanism.
