Facilitated Diffusion

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What is facilitated diffusion? In membrane, there are protein channels (pores) that allow polar molecules (soluble in water but not soluble in lipids) to move through them. The molecules that move through these channels never come into contact with the hydrophobic layer or the membrane's polar surface because these channels provide a continuous pathway for molecules that are moving through them. In this type of diffusion, like simple diffusion, no energy is consumed. Large and polar molecules require help to pass through the membrane. This help is done by a type of protein called carrier (transport) protein . To pass through the membrane, a molecules binds (temporarily) with carries protein in lipid bilayer and is transported from an area of higher concentration to an area of lower concentration.  Related topics: Simple Diffusion
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Definition of zoology/What is zoology?/branches-The Knowledge

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Define Zoology

Zoology (From Greek,zoon,+logous,to study) is the study of animals.It is a broad field of science because there is immense variety of animals and complexity occuring within them.Zoologists are specialized in specific subdisciplines.Ichthyology,for example ,is th e study of fishes,and ichthyologists study deeply the function,ecology,structure and evolution of fishes.These studies have uncovered  an amazing diversity of fishes.One large group of fishes known as cichlids is found in africa(1000 species),Central South America (300 species),India (3 species) and North America (1 species).Different color patterns,habitats and body forms are  found among species of this group of fishes.

Subdisciplines/fields/branches that are studied in zoology are as under:

Anatomy:

It is the study of internal structure of entire organisms and their body parts.

Cytology:

It is the study of structure and function of cells.

Ecology:

It is the study of interaction between orgsnisms and their environment.

Embryology:

It is the study of development of an animal from fertilization to birth or hatching.

Genetics:

It is the study of mechanism of transmission of  traits from parents to offspring.

Histology:

It is the study of tissues.

Molecular biology:

It is the study of subcellular details at molecular level of animal structure and function.

Parasitology:

It is the study of parasites that live on other animal at the expense of host.

Physiology:

it is the study of function of organisms and their parts.

Systematics:

It is the study of classification of,and the evolutionary interrelationship among,animal groups.

Specialization in zoology

Entomology:

It is the study of insects.

Herpetology:

It is the study of amphibians and reptiles.

Ichthyology:

It is the study of fishes.

Mammology:

It is the study of mammals.

Ornithology:

It is the study of birds

Protozoology:

It is the study of protozoa.

 

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