Our skeleton is made of more than 200 bones. Calcium and other minerals make the bone strong but slightly flexible. Bone is a living tissue with a blood supply. It is constantly being dissolved and formed, and it can repair itself if a bone is broken.
Function of the skeleton
The skeleton has four main functions:
- to support the body
- to protect some of the vital organs of the body
- to help the body move
- to make blood cells
The skeleton supports the body. For example, without a backbone we would not be able to stay upright.
Here are some examples of what the skeleton protects:
- the skull protects the brain
- the ribcage protects the heart and lungs
- the backbone protects the spinal cord
An X-ray image of the chest. The ribs form a cage-like structure that protects the organs inside.
Some bones in the skeleton are joined rigidly together and cannot move against each other. Bones in the skull are joined like this. Other bones are joined to each other by flexible joints. Muscles are needed to move bones attached by joints.
Making blood cells
There are different kinds of blood cells, including:
- red blood cells, which carry oxygen around the body in the blood
- white blood cells, which are involved in destroying harmful microorganisms in your body
These cells are made in the bone marrow. This is soft tissue inside our larger bones which is protected by the hard part of the bone which surrounds it.
Red blood cells
Worksheets and lesson ideas to challenge students aged 11 to 16 to think hard about plant and animal cells (GCSE and Key Stage 3)
Cells are not small planar structures! They are dynamic, three-dimensional bags of fluid containing a host of exciting organelles. Take time to help students appreciate that cells are the building blocks of living organisms. You can find ideas for teaching living/non-living here. Help students get an appreciation of scale, by stressing the relationship between atom, cell, tissue and organ. Taking epithelial cells from you cheek and showing these to the class can be a good bridge – i.e. explicitly linking the organism(you!) to the cell. A fun homework is to challenge students to make models of different specialised cells – you will be amazed by their creativity!
Labelling and drawing plant, animal and specialised cells
Key Stage 3 activity on labelling animal, plant and specialised cells.Students are given a worksheet showing basic animal cells. They modify the original diagram to create a series of new cells. This is a great and easy way to assess understanding of cell structure and help students see the features that are shared between different cells. (PDF)
GCSE activity labelling plant and animal cells. Students label plant and animal cells. They consider which organelles are shared between plants, animals and fungi. Students imagine what the common ancestor of all three groups could have looked like. (PDF)
Comparing plant and animal cells
GCSE activity comparing animal and plant cells worksheet. Students complete a Venn diagram to compare plant and animal cells. The activity can be modified to include bacterial cells and other cell types. It is a powerful approach for teaching the idea of compare and contrast. (PDF)
Functions of cell organelles
GCSE and Key Stage 3 worksheet on plant cell organelles. Students annotate a cartoon image of a labelled plant cell. They have to use their imagination to explain what each organelle would say if they could talk. This resource was contributed by Jane Masters (@mrsjmasters). View Jane’s blog at https://pedagoggles.wordpress.com/.
GCSE worksheet on cell structure and organelle function worksheet. Students compare city parts to cell organelles. They discuss the limitations of using analogies in science. You could extend the activity by challenging students to come up with their own analogy for a specialised cell. (PDF)
Comparing prokaryotic and eukaryotic cells
GCSE worksheet comparing prokaryotic and eukaryotic cells. Students label electron micrographs of prokaryotic and eukaryotic cells. We then look at a recent tree of life and consider how much diversity eukaryotic and prokaryotic organisms make up. (PDF)
Labelling eukaryotic cells
A Level worksheet for students to label a eukaryotic cell using electron micrographs. Sometimes students find it difficult to make links between how cells appear under the microscope and how they are represented in textbooks. Here, students are shown annotated electron micrographs. They use this to label a typical textbook diagram of a eukaryotic cell. Students consider whether the diagram or the electron micrographs represent what cells really look like. This worksheet could be easily adapted for plant cells. It makes a simple labelling activity much more challenging. It was contributed by Thomas Kitwood. (PDF)
- Cell structure
- Cell division
- Movement across membranes
- MRS GREN