Red blood cell, also called erythrocyte, cellular component of blood, millions of which in the circulation of vertebrates give the blood its characteristic colour and carry oxygen from the lungs to the tissues. The mature human red blood cell is small, round, and biconcave; it appears dumbbell-shaped in profile. The cell is flexible and assumes a bell shape as it passes through extremely small blood vessels. It is covered with a membrane composed of lipids and proteins, lacks a nucleus, and contains hemoglobin—a red, iron-rich protein that binds oxygen.
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blood: Red blood cells (erythrocytes)
The red blood cells are highly specialized, well adapted for their primary function of transporting oxygen from the lungs to all of the body tissues. Red cells are approximately 7.8 μm (1 μm = 0.000039 inch) in diameter and have the form of biconcave…READ MORE
The function of the red cell and its hemoglobin is to carry oxygen from the lungs or gills to all the body tissues and to carry carbon dioxide, a waste product of metabolism, to the lungs, where it is excreted. In invertebrates, oxygen-carrying pigment is carried free in the plasma; its concentration in red cells in vertebrates, so that oxygen and carbon dioxide are exchanged as gases, is more efficient and represents an important evolutionary development. The mammalian red cell is further adapted by lacking a nucleus—the amount of oxygen required by the cell for its own metabolism is thus very low, and most oxygen carried can be freed into the tissues. The biconcave shape of the cell allows oxygen exchange at a constant rate over the largest possible area.
The red cell develops in bone marrow in several stages: from a hemocytoblast, a multipotential cell in the mesenchyme, it becomes an erythroblast (normoblast); during two to five days of development, the erythroblast gradually fills with hemoglobin, and its nucleus and mitochondria (particles in the cytoplasm that provide energy for the cell) disappear. In a late stage the cell is called a reticulocyte, which ultimately becomes a fully mature red cell. The average red cell in humans lives 100–120 days; there are some 5.2 million red cells per cubic millimetre of blood in the adult human.
Though red cells are usually round, a small proportion are oval in the normal person, and in certain hereditary states a higher proportion may be oval. Some diseases also display red cells of abnormal shape—e.g., oval in pernicious anemia, crescent-shaped in sickle cell anemia, and with projections giving a thorny appearance in the hereditary disorder acanthocytosis. The number of red cells and the amount of hemoglobin vary among different individuals and under different conditions; the number is higher, for example, in persons who live at high altitudes and in the disease polycythemia. At birth the red cell count is high; it falls shortly after birth and gradually rises to the adult level at puberty.
Colour is a powerful and important communication tool, and it is tied to religious, cultural, political and social influences.
By stopping to consider what each colour represents and is linked to in the ‘real world’ we can make informed design decisions that ensure we appeal to our target audience. Without this consideration we run the risk of offending the very people were are designing for.
[Notice: Learn more about colour and design processes at The Future of Web Design New York City on Nov 16-17]
#1 It Affects your Mood
Most of us have a favourite colour or prefer some colours over others. This is because can affect our moods so we surround ourselves in the colours that have a positive impact on our mood.
Red can boost your energy, yellow often makes people feel happier, and blue is proven to bring down blood pressure and slow your heart rate which is why it is often associated with being relaxing. If you combine the happiness of yellow and the relaxing feel of blue you get green, a very pleasing colour for many people.
Mental health units are known to use pastel tones on their walls so that patients feel calm, happy, and relaxed. Walls that are beige with a pink tint combined with mint green floors are a popular combination as it is said to create a soothing, harmonious and calm area. At the other end of the spectrum, literally, schools tend to user bright colours that appeal to children.
When choosing colours for your next design it is important to consider how they will combine and sit with the other elements on the page and what impact that will have on the mood of your audience.
#2 Colours Communicate Invisibly
Wassily Kandinsky was one of the first pioneers of colour theory. A renowned Russian painter and art theorist, he is often considered the founder of abstract art. Kandinsky believed the following colours communicate the following qualities:
- Yellow – warm, exciting, happy
- Blue – deep, peaceful, supernatural
- Green – peace, stillness, nature
- White – harmony, silence, cleanliness
- Black – grief, dark, unknown
- Red – glowing, confidence, alive
- Orange – radiant, healthy, serious
#3 Colour has Cultural Significance
Different colours mean different things in different places. This is extremely important for designers to know because without an awareness of the cultural significance of a particular colour, you risk offending your entire target audience.
Purple for example is a colour of mourning in Thailand. In western culture however, it is associated with royalty, luxury, wealth and sometimes magic. The brand colour for Thai Airways is purple. On first glance this seems like a huge error on their part because as mentioned above, purple is a colour of mourning in Thailand.
It is most likely however, that the Thai Airways website isn’t aimed at locals but at tourists, therefore if westerners view the site and see purple it will associate Thai Airways with values such as luxury and comfort.
Other examples are:
- In western cultures black is a colour of mourning
- In Japan however it is a colour of honour, with white the colour of mourning
- Red in the west represents danger, love, passion
- In India it is a colour of purity, in China it is a colour of good luck and in South Africa it is a colour of mourning
- Yellow represents courage in Japan, mourning in Egypt and hope in the West
#4 Colour can be Inspired by our Surroundings
We live in a colourful world, a world that acts as the perfect inspirational trigger for design. The best thing about looking to the environment for design solutions is that the palette is always changing, from autumnal oranges to cold winter blues. So where better to look than out of your window, take in the colours and then apply them to your designs.
Drawing inspiration from nature for your designs also makes you look at the world differently. Normally we whiz by from place to place but you notice the finer details and undiscovered gems when you actually stop to take it in.
#5 Colour has Political Associations
Individual political parties are associated with one colour or another. Depending on whom your audience is, this might prove to be valuable information when designing.
The association between political parties and colours isn’t a new connection but it is often taken for granted. In the UK for example the following pairings exist:
- Labour – Red
- Conservative – Blue
- Liberal Democrats – Yellow
- The Green Party – Green
If a colour is representative of a political party then the values and behaviours that the party is known for can be suggested through the use of this colour.
- Red is often linked to socialism and communism
- White has links to pacifism and the surrender flag. In contrast to this, black is a colour that is used in conjunction with anarchism.
- Working class Nazism is associated with the colour brown as the SA were known as the ‘brownshirts’.
A design with one of these colours as the dominant shade may well hint at a right wing or a left wing preference or at extreme behaviours.
#6 Religion can be Linked to Colours
As with politics, colours are representative of certain religions. So as not to unintentionally offend anyone through your designs, some examples of these colour/religion associations are:
- Green is considered to be the holy colour of Islam
- Judaism is represented by the colour yellow
- In Hinduism, many gods have blue skin
- White is linked to peace across many religions
Again this may only be necessary information if you are designing a site that has specific links to religion but it also emphasises that a thorough knowledge of your audience is a fundamental part of the design process.
#7 Age Affects People’s Colour Preferences
Colour expert Faber Birren carried out many studies into this area and in his book Color Psychology and ColorTherapy, he states that for both genders, blue and red “maintain a high preference throughout life”. He found that yellow is popular with children but as become move into adulthood it shows less popularity. Birren found that “with maturity comes a greater liking for hues of shorter wave length (blue, green, purple) than for hues of longer wave length (red, orange, and yellow)”
Another factor that influences people’s colour preferences is that throughout their life there will be social and cultural changes and this can directly impact on their favourite colours. Some knowledge of what colours certain age ranges prefer can be valuable for designers. If you were designing a website for a toy store or a children’s TV channel, then knowing they prefer bright colours and yellow in particular would help with your design decisions.
Likewise, if you designed a website for a charity whereby the audience was to be the older generation then blue, green or purple might be ideal, based on Birren’s findings.
Colour is a complex subject with many strands and it has the power to subliminally convey values and stories. Please share your thoughts and opinions about colour, in the comments below.