Answer:
The human cell system has a pretty advanced and effective way of communication. This communication between cells, whether it be of a single system, or between systems, is carried out by chemical reactions and gradients, and also through the intercession of molecules known as neurotransmitters. This is the case of the nervous system and its means of communication.
When we talk about neurotransmitters (the messengers) and neuroreceptors (the gatekeepers that receive the message and produce a reaction), we are literally talking about communication in the nervous system.
There are two types of neuroreceptors for trasmitters: the ionotropic (ligand-gated ion channels) and the metabotropic (second-messenger gated receptors, or G-protein coupled receptors). While the first type depends entirely on the availability of a ligand that binds to the receptor to open up the influx of ions from outside and inside of the cell to create a gradient that will ensure a cell response, the second does not open any ion channels and literaly what it does is receive the message from a neurotransmitter, and through the G-protein bound to the receptor, once it gets the necessary message, detaches and carries out the information to the cell. This is broadly how neurotransmittion can be carried out in the nervous system.
Answer:
Prophase II meiosis-chromosomes-6 and 12 DNA molecules per cell.
Explanation:
Meiosis is a unique type of division that occur in cells in which the chromosome number is decreased to half with the creation of haploid cells. It can be referred to as reduction division and it mostly occurs in organisms which go through sexual reproduction.
In prophase II , the nucleoli and nuclear membrane disappear.
The chromatids reduces in length to become short and thick .
The centromeres migrates to the polar regions and set the spindle fibres in place for the second meiotic division.
Therefore, at Prophase II of meiosis
The daughter cells are haploid. Its haploid cells should possess six chromosomes and 12 DNA molecules.
Answer:
D. is responsible for most of the skin's structural strength.
Explanation:
A. contains no blood vessels.
False. The dermis contains blood vessels together embedded in it along with the sweat and sebaceous or oil glands, hair follicles, and nerve endings.
B. functions as a padding and insulation.
False. The fat layer that is located below the dermis is the one responsible for padding and insulation.
C. is divided into three distinct layers
False. The dermis is divided into only two separate layers. These are the papillary layer or the upper layer and the reticular layer or the lower layer.
D. is responsible for most of the skin's structural strength.
Yes, the dermis functions for providing the skin's structural strength because of it's thick fibrous and elastic tissue layer. This layer consists primarily of collagen and elastin that also allows for the skin's flexibility.
E. is made of epithelial tissue.
False. The dermis is made up of fibrous and elastic tissue. It is the epidermis which is composed of the epithelial tissue.
In any good web, which organisms has the LEAST available energy?
D) animals or carnivores
Answer:
projections that help them move
Explanation:
Euglena and paramecium both belong to the Kingdom Protista. They are very minute single cellular organisms but have many differences among them. Paramecium is more similar to animals in many of its characteristics while Euglena is more similar to plants in its characteristics. This is because Euglena just like plants can make their own foods through chloroplast while paramecium just like animals cannot make own food.
However what is common in both of these are projections that help them move
. Paramecium have projections called cilia around the whole body while Euglena has a whip like flagella which helps it to move.
Hope it help!
