Hello aspirant

A prokaryote is a relatively simple single celled organism. Previously there had been only one kingdom of prokaryotes known as Monera

But as Scientist discovered new and more forms of life new kingdom had to be created. there are two prokaryotic kingdoms , Eubacteria and Archaea.

Hello ,

The features of Gap Junction is as follows :

1. It permits substances to pass between cells without entering extracellular fluid
2. Are composed entirely of integral membrane protein called connexons
3. Each connexons are made up of six protein subunit called connexins
4. These gap junctions are present in abundant amount in cardiac muscles which are called intercalated discs
5. Because of this gap junction cardiac muscle works as a single functional syncytium
6. Gap junctions are also present in single unit smooth muscles which are present in visceral organs
7. Mutations in connexin leads to many human disease namely X-linked Charcot Marie tooth disease, Clouston syndrome, Cataract, atrial fibrillation and congenital sensorineural hearing loss.

Hello ,

Here is all that you need to know about Histotoxic Hypoxia :

• Occurs due to blockage of cellular enzymes that utilize oxygen
• Commonly happens in cyanide poisoning
• Cyanide inhibits cytochrome oxidase enzyme in mitochondria leading to blockage of oxidative phosphorylation
• Alveolar PO2 and Arterial PO2 and oxygen content may be normal
• Tissue can't utilize oxygen, Venous PO2 and oxygen content are elevated
• Arteriovenous O2 difference is reduced
• Oxygen therapy is not helpful

Hello Student,

It is the lateral deviation of the great toe at the metatarsophalangeal joint . It is more common in women than in men and is associated with misfitting  pointed shoes. They are unable to move their great toe away from the second toe because the sesamoid bones in the head of first metatarsal bone is displaced  and lies in the space between heads of the first and second metatarsal bones.

Hello ,

Role of adrenal medulla is as follows :

The adrenal medulla constitutes of chromaffin cells, which help in secretion of nor-adrenaline/norepinephrine and adrenaline/epinephrine, these are referred to as catecholamines

Adrenaline and nor-adrenaline are rapidly secreted in response to stress of any kind and during emergency conditions and are known as flight or fight hormone or emergency hormones.

• These hormones cause pupillary dialation, enhance alertness , cause piloerection. Both increase heart rate and respiratory rate.
• Catecholamines stimulate the breakdown of glycogen resulting in rise of blood glucose

Hypersecretion of adrenal medulla may occur due to its tumour known as Pheochromocytoma

Hello,

It involves number and types of genes as well as chromosomes present in  different species and the variations in the genes and their alleles in the same species.

In India there is more than 50000 genetically different strains of rice and 1000 varieties of mongo. Rauwolfia vomitoria has different concentration potential of the compound reserpine due to genetic diversity.

Hello Student,

Species Diversity can be described as follows :

• It is the variety in the number and richness of the species of a region
• Number of individuals of different species represent species evenness
• Number of species per unit area is called species richness
• Species diversity is a product of both species richness and evenness

Hope this Helps

Hello Student ,

Important points about tropical evergreen rain forest :

• These are found in equitorial and subequitorial warmth and heavy rainfall
• They show maximum biodiversity , one hector may contain upto  200 types of trees.
• Productivity of these forests is about 12000k.cal/m²/year
• These are found in congo basin of Africa, Amazon Basin of South America .
• In India these are found in Western Ghats, Andaman Nicobar Island, Assam
• Vegetation found is Mahogong , Ebony , Rubber Tree, Cinnamon
• Mosses, Lichens, ferns, orchids and Lianas are abundant

Hello,

The reasons for high diversity in Tropical regions are :

• These regions receive more sunlight than any other regions, this helps in more productivity.
• These regions have less distortions or variations in seasons and have a nearly constant environment.

Best Wishes.