Zusammenfassung der Ressource
1.1 Introduction to cells
- Cell theory
- Cells are the smallest unit of life
- All living things consist of cells
- Cells come from pre-existing cells
- Function of life
- Homeostasis
- Organism's metabolic activities are in a state of balance
- Ex : Body temperature
- Nutrition
- process- living things take in materials from its environment for growth
and repair
- Growth
- Increase in cell size and volume
- Reproduction
- living things produce offsrping
- 2 types
- asexual reproduction--one
parent and the offspring are identical to
the parent
- sexual reproduction--two
parents and the offspring is a
combination of both parents
- Response
- Action or movement- application of a stimulus.
- Metabolism
- chemical reactions
involved in maintaining the
living state of the cells and
the organism
- Excretion
- Removal of waste products
- Surface area : volume ratio
- Smaller the cells
- High surface area to volume ratio
- Limit cell size
- High ratio
- Function of life - better
- Differentiation
- A less specialized cell develops or matures to
become more distinct in form and function.
- Stem cells
- Produce cells- pluripotent
- Affecting cells, organs or
tissues.
- The capacity of stem cells to divide and differentiate along different pathways is necessary in
embryonic development and also makes stem cells suitable for therapeutic uses.
- Therapeutic use of stem cells from specially created embryos, from the umbilical cord blood of a
new-born baby and from an adult’s own tissues.
- multicellular organisms show emergent properties
- Example: cells form tissues, tissues form organs, organs form organ systems
and organ systems form multicellular organisms. Greater than the composition
of its parts.
- For example your lungs are made of cells. Not much use. Many cells working as a unit that allow the
lungs to perform their function.
- Calculation
- Magnification
- Size of drawing / size of specimen
- Actual size