Qiushi bai pj3 final

The number of bones

in a human body

THE NUMBER OF BONES IN A HUMAN BODY

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THE NUMBER OF BONES IN A HUMAN BODY.

Table Of Contents

04

There are 29 bones in the human head.

08 12

Human‘s arms have 54 bones, and they formed a human upper limb.

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06 Humans have 24 ribs (12 pairs). The first seven sets of ribs, known as "true ribs"

14 The pelvis is made up of 6 bones: 2 ilium bones, 2 ischium bones and 2 pubic bones

in hunman's cervical vertebrae

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In the human vertebral column there are normally thirty-three vertebrae

The lumbar vertebrae consist of five individual cylindrical bones that form the spine in the lower back.

18 There are 206 bones in the human's body

There are 62 bones in the human's leg and feet.

THE NUMBER OF BONES IN A HUMAN BODY

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07 bones

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THE NUMBER OF BONES IN A HUMAN BODY.

X-ray image of

human head

29 They consist of 8 cranial bones, 14 facial bones,

The human skull is the bony structure that forms

the hyoid bone, and 6 auditory (ear) bones.

the head in the human skeleton. It supports the

The 8 cranial bones are the frontal, 2 parietal,

structures of the face and forms a cavity for the brain.

occipital, 2 temporal, sphenoid, and ethmoid

Like the skulls of other vertebrates, it protects the

bones. The 14 facial bones are the maxilla,

brain from injury.

vomer and 2 palate bones.The hyoid bone is horseshoe-shaped bone at the base of the

tongue. The 6 auditory ossicles (little bones) are the malleus, incus and stapes in each ear.

The skull consists of two parts, of different

embryological origin–the neurocranium and the

facial skeleton (also called the viscerocranium).

The neurocranium (or braincase) forms the protective cranial cavity that surrounds and houses the brain and brainstem. The facial skeleton is formed by the bones supporting the face.

THE NUMBER OF BONES IN A HUMAN BODY

mandible, zygoma, lacrimal, nasal,turbinate,

There are 29 bones in a human head.

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07bones

THE NUMBER OF BONES IN A HUMAN BODY.

in a hunman cervical vertebrae

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In many species, though not in mammals, the cervical vertebrae bear ribs. In many other groups, such as lizards and saurischian dinosaurs, the cervical ribs are large; in birds, they are small and completely fused to the vertebrae. The vertebral transverse processes of mammals are homologous to the cervical ribs of other amniotes.

In vertebrates, cervical vertebrae (singular: vertebra) are the vertebrae of the neck, immediately below the skull. Thoracic vertebrae in all mammalian species are those vertebrae that also carry a pair of ribs, and lie caudal to the cervical vertebrae. Further caudally follow the lumbar vertebrae, which also belong to the trunk, but do not carry ribs.

In reptiles, all trunk vertebrae carry ribs and are called dorsal vertebrae.

In humans, cervical vertebrae are the smallest of the true vertebrae, and can be readily distinguished from those of the thoracic or lumbar regions by the presence of a foramen (hole) in each transverse process, through which the vertebral artery

THE NUMBER OF BONES IN A HUMAN BODY

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24 Humans have 24 ribs (12 pairs).

The first seven sets of ribs, known as "true ribs"

H

umans have 24 ribs (12 pairs). The first seven sets of ribs, known as "true ribs" (costae verae) also known as vertebrosternal ribs, are directly attached to the sternum through the costal

cartilage. Rib 1 is unique and harder to distinguish than other ribs.

It is a short, flat, C-shaped bone. The vertebral attachment can be found just below the neck and the majority of this bone can be found above

THE NUMBER OF BONES IN A HUMAN BODY.

the level of the clavicle. The ribcage is separated from the lower abdomen

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by the thoracic diaphragm which controls breathing. W h e n t h e diaphragm contracts, the thoracic cavity is expanded, reducing intrathoracic pressure and drawing air into the lungs.

This happens through one of two actions (or a mix of the two): when the lower ribs the diaphragm connects to are stabilized by muscles and the central tendon is mobile, when the muscle contracts t h e central tendon is drawn down, compressing the cavity under neath and expanding the thoracic cavity downward.

In general, human ribs increase in length from ribs 1 through 7 and decrease in length again through rib 12. Along with this change in size, the ribs become progressively oblique (slanted) from ribs 1through 9, then less slanted through rib.

human chest, with ribs labelled

THE NUMBER OF BONES IN A HUMAN BODY

X-ray image of

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33 In a human vertebral column there are normally thirty-three vertebrae

THE NUMBER OF BONES IN A HUMAN BODY.

T

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he vertebral column, also known as the

the cervical spine, thoracic spine, lumbar spine,

backbone or spine, is par t of the axial

sacrum and coccyx. There are seven cervical

skeleton. The vertebral column is the defining

ver tebrae, t welve thoracic ver tebrae and five

characteristic of a vertebrate, in which the notochord

lumbar vertebrae. The number of vertebrae in a region

(a flexible rod of uniform composition) found in all

can var y but overall the number remains the

chordates has been replaced by a segmented series

same. The number of those in the cervical region

of bones–vertebrae separated by intervertebral discs.

however is only rarely changed.The vertebrae

The vertebral column houses the spinal canal,a cavity

of the cervical, thoraic and lumbar spines are

that encloses and protects the spinal cord.

independent bones, and generally quite similar.

The vertebrae in the human vertebral column are

The vertebrae of the sacrum and coccyx are usually

divided into different regions, which correspond to the

fused and unable to move independently. Two

curves of the spinal column. The ar ticulating

special vertebrae are the atlas and axis, on which

vertebrae are named according to their region of the

the head rests.

spine. Vertebrae in these regions are essentially alike, with minor variation. These regions are called

human vertebral column.

THE NUMBER OF BONES IN A HUMAN BODY

Photo of

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54 Human‘s arms have 54 bones, and they formed a human upper limb.

The humerus is one of the three long bones of the arm. It joins with the scapula at the shoulder joint and with the other long bones of the arm, the ulna and radius at the elbow joint. The elbow is the hinge joint between the end of the humerus and the ends of the radius and ulna. The humerus cannot be broken easily. Its strength allows it to handle

THE NUMBER OF BONES IN A HUMAN BODY.

loading up to 300 pounds (140 kg).

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Photo of human arm

Photo of human arm

Photo of human hand

The human hand has five fingers and 27 bones, not including the sesamoid bone, the number of which varies between people,[3] 14 of which are the phalanges (proximal, intermediate and distal) of the fingers. The metacarpal bones connect the fingers and the carpal bones of the wrist. Each human carpal bones.

THE NUMBER OF BONES IN A HUMAN BODY

hand has five metacarpals[4] and eight

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14

THE NUMBER OF BONES IN A HUMAN BODY.

Photo of

human lumbar

05 The lumbar vertebrae consist of five individual cylindrical bones that form the spine in the lower back.

In tetrapod anatomy, lumbar is an adjective that means of or pertaining to the abdominal segment of the torso, between the diaphragm and the sacrum. The lumbar region is sometimes referred to as the lower spine, or as an area of the back in its proximity.

In human anatomy the five vertebrae in the lumbar region of the back are the largest and strongest in the movable part of the spinal column, and can be distinguished by the absence of a foramen in the transverse process, and by the absence of facets on the

the spine curves outward. The actual spinal cord (medulla spinalis) terminates between vertebrae one and two of this series, called L1 and L2. The nervous tissue that extends below this point are individual strands that collectively form the cauda equina.

In human anatomy the five vertebrae in the lumbar region of the back are the largest and strongest in the movable part of the spinal column, and can be distinguished by the absence of a foramen in the transverse process, and by the absence of facets on the sides of the body.

THE NUMBER OF BONES IN A HUMAN BODY

sides of the body.

In most mammals, the lumbar region of

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06 The pelvis is made up of 6 bones: 2 ilium bones, 2 ischium bones and 2 pubic bones

T

he pelvis (plural pelvises) is either the lower part of the trunk of the human

THE NUMBER OF BONES IN A HUMAN BODY.

body between the abdomen and the

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thighs (sometimes also called pelvic region

The pelvic region of the trunk includes

The two hip bones connect the spine with

of the trunk) or the skeleton embedded

the bony pelvis, the pelvic cavity (the

the lower limbs. They are attached to the

in it(sometimes also called bony pelvis, or

space enclosed by the bony pelvis), the

sacrum posteriorly, connected to each other

pelvic skeleton).

pelvic floor, below the pelvic cavity, and

anteriorly, and joined with the two femurs

the perineum, below the pelvic floor.The

at the hip joints. The gap enclosed by the bony

pelvic skeleton is formed in athe area

pelvis, called the pelvic cavity, is the section

of the back, by the sacrum and the coccyx

of the body underneath the abdomen and

and anteriorly and to the left and right

mainly consists of the reproductive organs

sides, by a pair of hip bones.

(sex organs) and the rectum.

Photo of

human pelvis

THE NUMBER OF BONES IN A HUMAN BODY

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Photo of human leg

The human leg, in the general sense, is the entire lower extremity or limb of the human body, including the foot, thigh and

The human foot is a strong and complex

even the hip or gluteal region; however,

mechanical structure containing 26

the definition in human anatomy refers

bones, 33 joints (20 of which are actively

only to the section of the lower limb

articulated), and more than a hundred

extending from the knee to the ankle

muscles, tendons, and ligaments.

(called crus in Latin; the posterior of the

The joints of the foot are the ankle and

crus is the sura).

subtalar joint and the interphalangeal

THE NUMBER OF BONES IN A HUMAN BODY.

articulations of the foot.

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62

There are 62 bones in a human leg and feet.

human foot

THE NUMBER OF BONES IN A HUMAN BODY

Photo of

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THE NUMBER OF BONES IN A HUMAN BODY.

Photo of

human body

T

he skeleton of an adult human consists

and a process which typically reaches

of 206 bones. It is composed of 237

completion in the third decade of life.

bones birth, which decreases to 206

In addition,the bones of the skull and face

bones by adulthood after some bones have

are counted as separate bones, despite

fused together.[1] It consists of 80 bones

b e i n g f u s e d n a t u ra l ly. S o m e re l i a bl e

in the axial skeleton and 126 bones in the

sesamoid bones such as the pisiform are

appendicular skeleton (32 x 2 in upper

counted, while others, such as the hallux

extremities including both arms and 31 x

sesamoids, are not.

2 in lower extremities including both legs).

Individuals may have more or fewer

Many small and often variable bones, such

bones than this owing to ana tomical

as some sesamoid bones, are not included

variations. The most common variations

in this count.

include additional cervical ribs or lumbar

The figure of 206 bones is commonly

repeated, but does have some peculiarities in its method of counting. It is taken of an adult

human—the number of bones in the skeleton

changes with age, as multiple bones fuse,

vertebrae. Sesamoid bone counts also may vary among individuals.

THE NUMBER OF BONES IN A HUMAN BODY

20 6

There are 206 bones in a human body

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INDEX THE NUMBER OF BONES OF HUMAN BODY

A

E

auditory (ear) bones 04

ethmoid bones 05

attachment 08

essentially 11

abdomen 08 articulating 10 axis 10 anatomical 21 adulthood 21

C

elbow 13 equina 15 enclosed 17 extremities 20

cranial bones 05

H hyoid bone 05

C-shaped 09

human ribs 09

characteristic 11

head rests 11

correspond 10

humerus 12

coccyx 10

THE NUMBER OF BONES IN A HUMAN BODY.

carpal 13

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B

F

bones 04

Further 06

backbone 10

fingers 12

D

femurs 17

L

dorsal vertebrae 06

lacrimal 05

decrease 09

lie caudal 07

distinguish 08

lungs 08

diaphragm connects 08

lumbar spine 11

despite 20

M

S

minor 10

spine 10

metacarpal 12

sacrum 10

medulla spinalis 15 mammals 14

P

scapula 12 skeleton 21

U

parieta 04

ulna 12

palate bones 04

upper extremities 20

phalanges 12 proximity 14 pisiform 20 peculiarities 20

N

T

nasal 05

temporal 05

notochord 11

turbinate 04

R

thoracic cavity 09 thoraic 10

V viscerocranium 04

radius 12

vomer 05

rectum 16

vertebral column 11

THE NUMBER OF BONES IN A HUMAN BODY

ribcage 08

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