Human head

Key takeaways

Human head belongs to science; place it in that map before memorising details.
Learn the definition first, then one example that makes the definition concrete.
Connect Human head to a quantity you can measure, compute or draw — that is where exam questions come from.
Reproduce the core statement of Human head from memory before moving on to harder problems.

Reference excerpt

In human anatomy, the head is at the top of the human body. It supports the face and is maintained by the skull, which itself encloses the brain.

Structure

The human head consists of a fleshy outer portion, which surrounds the bony skull. The brain is enclosed within the skull. There are 22 bones in the human head. The head rests on the neck, and the seven cervical vertebrae support it. The human head typically weighs between 2.3 and 5 kilograms (5.1 and 11.0 lb). Over 98% of humans fit into this range. There have been odd incidences where human beings have abnormally small or large heads. The Zika virus was responsible for underdeveloped heads in the 2015 and 2016. The face is the anterior part of the head, containing the eyes, nose, and mouth. On either side of the mouth, the cheeks provide a fleshy border to the oral cavity. The ears sit to either side of the head.

Blood supply The head receives blood supply through the internal and external carotid arteries. These supply the area outside of the skull (external carotid artery) and inside of the skull (internal carotid artery). The area inside the skull also receives blood supply from the vertebral arteries, which travel up through the transverse foramina of cervical vertebrae.

Nerve supply

The twelve pairs of cranial nerves provide the majority of nervous control to the head. Innervation to the muscles of the face, which allow one to do actions like smile or grimace, is primarily provided by the facial nerve, the seventh cranial nerve. The sensation to the face is provided by the branches of the trigeminal nerve, the fifth cranial nerve. Sensation to other portions of the head is provided by the cervical nerves. Modern texts are in agreement about which areas of the skin are served by which nerves, but there are minor variations in some of the details. The borders designated by diagrams in the 1918 edition of Gray's Anatomy are similar but not identical to those generally accepted today. The cutaneous innervation of the head is as follows:

Ophthalmic nerve (green) Maxillary nerve (pink) Mandibular nerve (yellow) Cervical plexus (purple) Dorsal rami of cervical nerves (blue) and others are in picture which show following in upper column

Function The head contains sensory organs: two eyes, two ears, a nose and tongue inside of the mouth. It also houses the brain. Together, these organs function as a processing center for the body by relaying sensory information to the brain. Humans can process information faster by having this central nerve cluster. The special senses of Olfaction, vision, taste, hearing and vestibular function are encoded by highly specialized sense organs and transmitted to the brain via cranial nerves. Structurally on the interior, the skull protects the brain and supports the facial region, while the jaw and oral cavity enable chewing, speech articulation, and the initial stages of digestion.

Society and culture For humans, the front of the head (the face) is the main distinguishing feature between different people due to its easily discernible features, such as eye and hair colors, shapes of the sensory organs, and the wrinkles. Humans easily differentiate between faces because of the brain's predisposition toward facial recognition. When observing a relatively unfamiliar species, all faces seem nearly identical. Human infants are biologically programmed to recognize subtle differences in anthropomorphic facial features.

People who have greater than average intelligence are sometimes depicted in cartoons as having bigger heads as a way of notionally indicating that they have a "larger head". Additionally, in science fiction, an extraterrestrial having a big head is often symbolic of high intelligence. Despite this depiction, advances in neurobiology have shown that the functional diversity of the brain means that a difference in overall brain size is only slightly to moderately correlated to differences in overall intelligence between two humans. The head is a source for many metaphors and metonymies in human language, including referring to things typically near the human head ( "the head of the bed"), things physically similar to the way a head is arranged spatially to a body ("the head of the table"), metaphorically ("the head of the class"), and things that represent some characteristics associated with the head, such as intelligence ("there are a lot of good heads in this company"). Ancient Greeks had a method for evaluating sexual attractiveness based on the Golden ratio, part of which included measurements of the head. Headhunting is the practice of taking and preserving a person's head after killing the person. Headhunting has been practiced across the Americas, Europe, Asia, and Oceania for millennia.

Clothing

Headpieces can signify status, origin, religious/spiritual beliefs, social grouping, team affiliation, occupation, or fashion choices. In many cultures, covering the head is seen as a sign of respect. Often, some or all of the head must be covered and veiled when entering holy places or places of prayer. For many centuries, women in Europe, the Middle East, and South Asia have covered their head hair as a sign of modesty. This trend has changed drastically in Europe in the 20th century, although is still observed in other parts of the world. In addition, a number of religions require men to wear specific head clothing—such as the Islamic taqiyah, Jewish yarmulke, or the Sikh turban. The same goes for women with the Muslim hijab or Christian nun's habit. A hat is a head covering that can serve a variety of purposes. Hats may be worn as part of a uniform or used as a protective device, such as a hard hat, a covering for warmth, a covering that meets sensory needs in some neurodivergent people, or a fashion accessory. Hats can also be indicative of social status in some areas of the world.

… excerpt ends here. Continue reading the full article.

Illustrations

Worked examples

Example 1 — a first encounter with Human head

Start with the simplest possible case. Write down what Human head claims or describes in one sentence, then invent the smallest concrete situation in which that sentence is true. In science, the smallest case is usually a single object, a single equation or a single measurement. Check that every symbol or term in your sentence has a meaning in that case.

Example 2 — changing one variable

Take the situation from Example 1 and change exactly one quantity: double it, halve it, or set it to zero. Predict what should happen to Human head before you calculate. Comparing your prediction with the result is the fastest way to find out whether you understand the idea or only the words.

Example 3 — an exam-style question

Typical questions about Human head ask you to (a) state it precisely, (b) apply it to given data, and (c) explain a limitation. Practise writing all three answers in under five minutes; the third part is what separates a full-mark answer from an average one.

Applications of Human head

In research: Human head appears in science research whenever the underlying quantities have to be modelled precisely. Papers usually cite it as a starting assumption and then explore where it breaks down.
In technology and industry: Engineering practice reuses Human head in design rules, simulations and safety margins. Knowing the idea lets you read a specification sheet and understand why the numbers look the way they do.
In the classroom: Human head is common in secondary-school and first-year university syllabi. It links to neighbouring topics Human head and neck, so understanding it makes those chapters shorter.
In everyday life: Look for Human head outside the textbook — in sport, cooking, traffic, electronics or the sky above you. An example you found yourself is remembered far longer than one you were given.

How to study Human head in 20 minutes

Read the reference excerpt below once, without taking notes.
Close the page and write down what Human head means in your own words.
Compare your version with the excerpt and mark what you missed.
Work through the three examples above with pen and paper.
Explain Human head out loud to somebody else — or to Teacher Smith in the lgStudy chat.

Frequently asked questions

What is Human head in simple terms?

In human anatomy, the head is at the top of the human body. It supports the face and is maintained by the skull, which itself encloses the brain.

Why does Human head matter?

Because it connects several science ideas at once: it gives you a definition you can apply, a quantity you can calculate, and a way to check whether a result is plausible.

How should I study Human head?

Read the excerpt, restate it from memory, then work through the examples and applications listed on this page. The five-step study plan above takes about twenty minutes.

What does this page cover?

It gives you a compact reference excerpt plus original lgStudy explanations, examples, applications and study material on Human head.