Cells and Microscopy

Mrs Nerg
 Movement
 Respiration
Sensitivity
Nutrition
Excretion
Reproduction
 Growth

 Skeleton

Protection - the cranium and ribs protect the brain and vital organs in the chest.

 Shape - gives shape to the body and makes you tall or short.

Support - holds your vital organs in place when playing sport. The vertebral column holds the body upright.

Movement - muscle are attached to bones, which are jointed. When the muscles contract the bones move.

Blood production - red blood cells (to carry oxygen) and white blood cells (to protect against infection) are produced in the bone marrow of some bones.

Joints

A joint is where two or more bones meet.

Synovial joints
 Cartilage reduces friction. Acts as a shock absorber.

Synovial fluid lubricates the joint.

Synovial membrane produces synovial fluid.

Tendon joins muscle to bone enabling movement.

Ligament joins bone to bone, stabilising the joint.

Limb Movements

Abduction – movement away from the mid-line of the body

Adduction – movement towards the mid-line of the body

Extension – straightening limbs at a joint

Flexion – bending limbs at a joint

Rotation – a circular movement around a fixed point
 
 

Muscles
 The process is called contraction. Muscles are attached to bones by strong tendons. When a muscle contracts, it pulls on the bone, and the bone can move if it is part of a joint.

Antagonistic Muscles
 Muscles which work in pairs with one contracting and the other relaxing.

Respiration
 Respiration is the chemical process of the body converting glucose and oxygen into energy whereas breathing is the physical process of inhaling oxygen and exhaling carbon dioxide.

Word Equation
 Oxygen + Glucose->Carbon Dioxide + Water + (Energy)

Structure of the Lungs
 The windpipe (trachea) branches into two bronchi(one to each lung). Cartilage rings in the walls of the windpipe help to keep it open however much you twist your neck. The bronchi split into smaller and smaller tubes called bronchioles. The bronchioles end in microscopic air sacs (alveoli). These air sacs are lined with mucus and are surrounded by a network of blood capillaries.

The layer of moisture in the air sacs lets gases dissolve so that they can diffuse quickly. The mucus in the trachea and bronchi is sticky so it traps any dust and micro-organisms which you breathe in.

The cells lining the air tubes are covered in tiny hairs called cilla. The cilia move back and forth to sweep the mucus upwards towards the throat. This helps to remove the dust and micro-organisms. The mucus is usually swallowed.

Fish Gills
 At the side of fishes’ heads, it is made up of many gill filaments which increase the surface area. The filaments contain lamellae, which have capillaries. Blood enter and leaves the capillaries through small blood vessels.
 Fish exchange gases in oxygen-rich waters, by sucking in the water, then pumping it over gills.

Magnification

Light microscope - use…