Differentiation of cells Adaptation Differentiation of cells

Differentiation Definition – give a dictionary definition of the word above. Give examples of differentiated cells Cellular differentiation is the process by which a less specialised cell becomes a more specialised cell type Examples you need to be aware of are: erythrocytes (red blood cells) and neutrophils derived from stem cells in bone marrow, xylem vessels and phloem sieve tubes from cambium;

Lesson 7 - Differentiation Learning Objectives Success Criteria define the term differentiation, with reference to erythrocytes, neutrophils describe and explain, how cells of multicellular organisms are specialised for particular functions explain the meaning of the terms tissue, organ and organ system Produce a resource to show how each of the cell types is differentiated Describe how the cell’s differentiation allows it to fulfill its role Produce a flow diagram to show how blood cells differentiate

Spec. Check describe and explain, with the aid of diagrams and photographs, how cells of multicellular organisms are specialised for particular functions, with reference to erythrocytes, neutrophils, epithelial cells, sperm cells, palisade cells, root hair cells and guard cells; explain, with the aid of diagrams and photographs, how cells are organised into tissues, using squamous and ciliated epithelia, xylem and phloem as examples;

How can cells be adapted? The amount of a certain organelle The shape of the cell The contents of the cell

Erythrocyte

Adaptations Organelles No nucleus, mitochondria, Golgi apparatus, rough endoplasmic reticulum Shape Biconcave discs Contents Contain lots of the protein haemoglobin

Neutrophil

Adaptations Organelles Many lymphocytes

Sperm Cells

Adaptations Organelles Many mitochondria Acrosome (lysosome) Shape Streamlined Undulipodium Content Half the number of chromosomes

Epithelial Cell

Squamous Epithelial Cell Flattened Smooth Secrete collagen and glycoproteins

Ciliated Epithelial Cell Covered in cilia Some release mucus

Palisade Cells

Adaptation Lots of chloroplasts for photosynthesis Laid end on Placed at top of leaf

Guard Cell

Adaptations Thick cell walls so inner cell wall does not stretch Contain chloroplasts to undergo photosynthesis

Root Hair Cell

Adaptations Large surface area