All About Bones The Skeletal System

How many bones can you name? DO NOW How many bones can you name?

Bones to Know: Appendicular Skeleton: Axial Skeleton: Skull Pectoral Girdle 6. Scapula 7. Clavicle Upper Limb 8. Humerus 9. Radius 10. Ulna 11. Carpals 12. Metacarpals 13. Phalanges Pelvic Girdle 14. Pelvis Lower Limb 15. Femur 16. Patella 17. Fibula 18. Tibia 19. Tarsals 20. Metatarsals 21. Phalanges Axial Skeleton: Skull 1. Skull 2. HyoidBone Vertebral Column 3. Vertebrae Thoracic Cage 4. Ribs 5. Sternum

Axial and Appendicular

Axial Portion

Skull

Vertebrate

Ribs

Sternum

Appendicular Portion

Pelvis

Clavicle

Scapula

What is the common name for the clavicle? What is the common name for the scapula?

Humerus

Radius and Ulna

Carpals

Metacarpals

Phalanges

Femur

Patella

Tibia and Fibula

Tibia/Fibula vs Radius/Ulna

Tarsals

Metatarsals

Phalanges

Tarsal Bones vs Carpal Bones

Types of Bones

How many bones are there?? In a newborn there are 300!!!!!

How many bones are there? In an adult, that are 206!!! That is almost 100 fewer than infants. What happened?

What is the largest bone? The Femur!

What is the smallest bone?

Exit Ticket Name the bones listed below. 4 3 1 5 2

Skeletal Disorders All About Bones

DO NOW Can you name any skeletal disorders? What do you know about them? What would you like to know?

Fractures

Activity Create a foldable (like the one we did for the organ systems) that details the different types of fractures. Name the fracture Give the definition of the fracture Draw it Classify the difficulty to heal (how do bones heal, what process?) There are 9 different fractures Compression fractures: usually occurs in the vertebrae, for example when the front portion of a vertebra in the spine collapses due to osteoporosis (a medical condition which causes bones to become brittle and susceptible to fracture, with or without trauma). Other types of fracture are: Complete fracture: A fracture in which bone fragments separate completely. Incomplete fracture: A fracture in which the bone fragments are still partially joined. In such cases, there is a crack in the osseous tissue that does not completely traverse the width of the bone.[4] Linear fracture: A fracture that is parallel to the bone's long axis. Transverse fracture: A fracture that is at a right angle to the bone's long axis. Oblique fracture: A fracture that is diagonal to a bone's long axis. Spiral fracture: A fracture where at least one part of the bone has been twisted. Comminuted fracture: A fracture in which the bone has broken into a number of pieces. Impacted fracture: A fracture caused when bone fragments are driven into each other. Avulsion fracture: A fracture where a fragment of bone is separated from the main mass.

Exit Ticket Which fracture do you think are the hardest to mend? Why? Which fracture do you think are the easiest to mend? Why?

Males vs. Females All About Bones

DO NOW How can you distinguish between males and females? Don’t just make a list, describe the differences.

Activity You are a world-renowned bone expert. You just received an urgent call from your Supervisor. He has informed you that a jogger has discovered a body in the woods. The body is nearly decayed and the police need to know if the victim is male or female.

Some clues There are distinct difference in the bones that distinguish males from females

The Pelvis Female Pelvic bones Broader sciatic notch Raised auricular surface Males Pelvic Bones Narrower sciatic notch Flat auricular surface

The Pelvis Figure 1. Female and male pelvic bones. (Source: Smithsonian Institution)

Male or Female? Figure 2. Pelvic bone of the skeleton in the cellar. (Source: Smithsonian Institution) Male

Male or Female? Male

Male or Female? Female

Male or Female? Male

Skull Male skulls Larger than females Larger brow ridge Sloping, less rounded forehead Larger projections behind ears Square chin Greater definition of muscle attachment areas on the back of the head

Skull: Male

Skull Female Smoother bone surfaces where muscles attach Less pronounced brow ridges More vertical forehead Sharp upper margins of the eyes orbits Smaller projections behind the ears Chin more pointed Larger, obtuse angle of the jaw

Skull: Female

Male or Female? Female

Male or Female? Female

Male or Female? Male

Checklist for examining the skull For each category, describe what you see and determine male or female for that feature. Brow ridge Neck muscle attachments Mastoid Process Upper eye orbit margin Angle of jaw Chin From there you can make a better estimate as to the sex.

Exit Ticket What is the easiest way to determine the gender (using the skeleton) of an individual, and why?

Off you go!! Work in small groups to determine the sex of the skeleton. Turn in work individually!

Determining Your Height All About Bones

Do Now Which bones do you think would be the best for determining the height of an individual. Defend your answer. You must pick one bone.

Determining Height from Bone Length It is possible to determine the height of an individual based on the length of one bone. This is useful because sometimes all that police recover is a few bones.

Activity In this activity you will look at the bones in the arm. Which are? And the bones in the leg.

Activity Break into groups of 4. 2 of you will measure the arm bones 2 of you will measure the leg bones Then compare your results How accurate are you to the actual height of the person? Which equation is more accurate?

Important Equations: Arms Males Height = (length of radius x 3.3) + 34 Height = (length of humerus x 2.9) + 27.8 Females Height = (length of radius x 3.3) + 32 Height = (length of humerus x 2.8) + 28.1

Important Equations: Legs Males Height = 2.42 x (tibia length in cm) + 81.93 Female Height = 2.90 x (tibia length in cm) + 61.53 Using the femur and tibia Height = 1.31 x (length of femur in cm + length of tibia in cm) + 63.05

Exit Ticket In some cases all that a forensics team has to go on is a bone. What are your conclusions regarding the level of accuracy you can obtain in predicting height based on one or two bones?