Chapter 4 Flashcards
Main functions of the skeletal system
There are 5
- Movement: Skeletal system provides points of attachment for muscles. Your legs and arms move when the muscles pull on the bones.
- Support: The backbone is the main support centre for the upper body. It holds your head up and protects your spinal cord.
- Protection: The bones of your skull protect your brain. Your ribs protect your lungs and heart from injury.
- Makes Blood: Red and white blood cells are formed by tissue called marrow, which is in the centre of the bone.
- Storage: Bones store minerals, such as calcium and phosphorus, for use by the body
What are the three main functions of the Skelton and give a brief description
Movement, protection, support
•supporting your soft tissues. Without a skeleton your skin and the organs inside your body would collapse
•protecting organs. This is the main role of your axial skeleton, which is made up of 80 bones. It includes your skull (which protects your brain), vertebrate (which protects your spinal cord), and ribs and sternum or breastbone (which protect your lungs and heart)
•Allowing movement. This is the main role of your appendicular skeleton
What does the axial skeleton consist of?
- the skull,
- spine,
- ribs
- sternum.
What does the appendicular skeleton consist of?
The appendages of the body, which are the
- shoulders,
- arms,
- hips,
- legs.
What are the Four basic bone shapes?
- Long- arms, legs and fingers
- Short- wrist and ankles
- Flat- skull and sternum
- Irregular- spine
Bone Structure
Typical Four Layers:
Periosteum: Covers Bones
Compact Bone: Lies beneath the periosteum
Spongy Bone: Lies beneath the compact bone
Bone Marrow: Fills the gaps between the spongy bone
Role of the Clavicle or Collarbone
holds the shoulder joint away from the rest of the upper body
Location and role of Scapula
The scapula is located on the back side of the ribcage and helps provide part of the shoulder joint and movement for the arms
What are joints
A joint is where two bones meet. It can be moveable or fixed
What would happen if we didn’t have joints
If we did not have joints we would find simple tasks like eating very difficult. Any movement needing bending would be impossible!!!!
Describe a hinge joint and how it works
Hinge joint: in this joint, the ends of the bones are shaped so that movement is allowed in only one plane- backwards and forwards like the hinge of a door. Hinge joints work like a lever and allow movement of 180o The ends of the bones in a hinge joint are covered by cartilage. Muscles work in pairs to contact and relax to move the joint
Describe a Ball and socket joint and how it works
Ball and socket joint: in this joint one bone had a ball-shaped surface that fits into a cup-shaped socket in the other bone. He bone with the ball at its end is able to complete all types of movement Ball and socket joints allow the joint to rotate in 360o allowing a lot of flexibility.
Both the ball and the socket are covered by a layer of cartilage.
Describe a pivot joint and how it works
Pivot joint: a pivot joint, moves by a ring-shaped bone turning around another bone shaped like a finger. Pivot joints allow bones to rotate around each other by 360o. The reason our neck does not rotate 360o fully is because muscles limit how far it will rotate.
The ends of the bones in a pivot joint are covered by cartilage
Describe a saddle joint and how it works
Saddle point: this allows movement in two directions but doesn’t allow the same amount of movement as a ball and socket joint. Provide stability to the bones while providing more flexibility than a hinge or gliding joint.
To protect your bones from wear what do joints have, give a brief description
Cartilage: a smooth and slippery material that covers the ends of bones that are moving against each other
Synovial fluid: which lubricates the bone ends and allows them to slide over each other freely
What is a ligament
Ligaments are bands of tough, flexible tissue that holds the bones in a joint together. Ligaments prevent the bones of the joking from moving too far apart
What is a tendon
Tissues that attach muscles to bones and hold the muscles in position.
When activated, muscles contract, becoming fatter and shorter. They pull on the bones they’re attached to, causing them to move
What are muscles
It is your muscles that move bones. Muscles are tissues that are able to contract (shorten) and be stretched
How many muscles are there in a single human body
640
Muscles can only pull. They cannot push. Describe how this works
Therefore, another muscle is required to return the bone to its original position
What are antagonistic pairs and give an example and explain
Antagonistic means that they work in opposition to each other.
The biceps and triceps are antagonistic muscles in your upper arm.
The biceps contracts contracts when activated, pulling your forearm up. The bicep then relaxes. To lower the forearm, the triceps contracts. The relaxed biceps is stretched back to its original shape and the arm is straightened
What is reproduction
The process by which parents produce new individuals. These new individuals are commonly called offspring
What is sexual reproduction
Reproduction usually requiring two parent
What is asexual reproduction
asexual means without sex, and so it only needs one parent
Describe sexual reproduction
Happens when a sperm from a male enters an egg from a female and fertilises it. The process is called fertilisation. Sperm and eggs are special reproductive cells, known as gametes. The male gamete is the sperm and the female gamete is the egg. Fertilisation results in a new cell called a zygote. The zygote then grows by dividing to form many copies of itself. The zygote eventually grows and develops into a new individual.
Describe all the roles in a plant
In sexual production pollen produced by anthers needs to be deposited onto the stigma. This is called pollination. Sexual reproduction requires two parents
Anther- produces pollen that contains the male gamete
Stigma- site for pollen to be deposited
Ovary- produces the eggs and encloses the seeds when they form
Filament- holds the anther
Sepal- covers the flower in the bud and protects it
Style- connects the stigma to the ovary
Petal- coloured parts that attract animals to allow pollination