Cheat sheet
The whole topic on one page.
Outcome SC4-CLS-01
A student describes the unique features of cells in living things and how structural features can be used to classify organisms.
- SC4-WS-01 uses scientific tools and instruments for observations
- SC4-WS-04 follows a planned procedure to undertake safe and valid investigations
- SC4-WS-08 communicates scientific concepts and ideas using a range of communication forms
Cell theory
- All living things are made of cells.
- The cell is the basic unit of structure and function.
- All cells come from pre-existing cells.
- All cells contain DNA · energy flow happens in cells · same basic chemistry.
Hooke named cells (1665) · van Leeuwenhoek saw living ones · Schleiden & Schwann · Virchow.
Two processes, two organelles
- Photosynthesis · chloroplast
- carbon dioxide + water → glucose + oxygen (light, chlorophyll)
- Cellular respiration · mitochondria
- glucose + oxygen → carbon dioxide + water + energy
All cells respire. Only cells with chloroplasts photosynthesise. Plants do both.
Organelles
| Cell membrane | Controls what enters and leaves the cell. |
|---|---|
| Cytoplasm | Jelly-like fluid where the cell's reactions happen. |
| Nucleus | Control centre. Holds DNA, the cell's instructions. |
| Mitochondria | Release energy from glucose — cellular respiration. |
| Chloroplast | Makes glucose from light — photosynthesis. |
| Vacuole | Stores water and nutrients; keeps plant cells firm. |
| Cell wall | Rigid outer layer that supports and protects the cell. |
| Nucleolus | Dense spot inside the nucleus that makes ribosomes. |
| Ribosomes | Tiny dots that build proteins. |
| Rough endoplasmic reticulum | Folded membranes dotted with ribosomes; makes and moves proteins. |
| Smooth endoplasmic reticulum | Tubes with no ribosomes; makes lipids (fats) and breaks down toxins. |
| Golgi apparatus | Packages proteins into vesicles for delivery. |
| Vesicles | Small bubbles that carry substances around the cell. |
| Lysosome | Bag of enzymes that breaks down waste and worn-out parts. |
| Centrioles | Pair of tubes that organise cell division. |
| DNA (no nucleus) | Bacterial DNA floats free in the cytoplasm. |
| Flagellum | Whip-like tail that some bacteria use to move. |
Which cell has what
| Animal cell | Plant cell | Bacterium | Fungal cell (yeast) | |
|---|---|---|---|---|
| Cell wall | No | Yes (cellulose) | Yes | Yes (chitin, not cellulose) |
| Nucleus | Yes | Yes | No — DNA floats free | Yes |
| Chloroplasts | No | Yes (green parts) | No | No |
| Mitochondria | Yes | Yes | No | Yes |
| Vacuole | Small / temporary | Large, central | No | Yes |
| Ribosomes | Yes | Yes | Yes (smaller) | Yes |
| Shape | Round or irregular | Regular, box-like | Much smaller than plant/animal cells | Eukaryote — yeast is single-celled, mushrooms multicellular |
Test key terms · Wednesday 9 September, periods 5 & 6
microscopic · macroscopic · parts of a microscope · magnification · resolution · field of view · unicellular · multicellular · prokaryotes · eukaryotes · membrane-bound organelles · cellular respiration · photosynthesis · organelles · specialised cells · differentiation · zygote · embryo · stem cells · classification · dichotomous key · domain · organism · kingdom · phylum · class · order · family · genus · species · taxonomy · vascular and non-vascular plants
Resolution = detail (see two close points as separate). Field of view = the circle you see; shrinks as magnification rises. Cell size = FOV ÷ cells across.
Zygote (fertilised egg) → embryo (ball of stem cells) → differentiation → specialised cells → tissues → organs.
Domain sits above kingdom (Bacteria, Archaea, Eukarya). Taxonomy = naming and classifying. Vascular plants have xylem/phloem (ferns, conifers, flowering); non-vascular do not (mosses, liverworts).
Microscope
total = eyepiece × objective
10× eyepiece · 4×, 10×, 40× objectives → 40×, 100×, 400×.
- Start on lowest power; coarse focus on low power only.
- Carry with two hands: arm and base.
- Drawings: pencil, no shading, ruled label lines, title, magnification.
Living things · MRS GREN
Movement · Respiration · Sensitivity · Growth · Reproduction · Excretion · Nutrition
Plus: made of cells. Fire fails. A Paramecium passes with one cell.
Levels of organisation
cell → tissue → organ → system → organism
Classification
Kingdom → Phylum → Class → Order → Family → Genus → Species
King Philip Came Over For Good Spaghetti.
Binomial: Homo sapiens
Genus capital, species lowercase, italics. Six kingdoms: Animalia, Plantae, Fungi, Protista, Archaea, Bacteria.
Dichotomous key
Paired yes/no choices on structural features. Adaptations: structural (body) or behavioural (action).
Everything that can be tested
Syllabus content, word for word, with the deck that covers it.
Cells
Outline cell theory
Identify which cell structures and organelles are common in plant and animal cells
Describe the functions of the cell membrane, cytoplasm, nucleus containing DNA, mitochondria and chloroplasts
Compare the structure of plant and animal cells to identify similarities and differences
Conduct an investigation to observe and record the similarities and differences between different cells, including fungi, bacteria, plant and animal cells, using microscopes and/or images obtained from microscopes
Identify cellular respiration via mitochondria, and photosynthesis via chloroplasts, as examples of important processes that take place in specialised organelles
Draw single-celled organisms observed under a microscope
Describe the role of specialised cells in multicellular organisms and explain why they are needed
Represent the arrangement of specialised cells in tissues and in organs
Examine the relationship between structure and function for a range of specialised cells
Conduct a practical investigation to observe and compare prepared slides of specialised cells
Classification of living things
Describe the characteristics of living things
Discuss the role and importance of classification in ordering and organising the diversity of life on Earth
Classify species using scientific conventions from the binomial system of classification, including kingdom, phylum, class, order, family, genus and species
Conduct an investigation to observe and identify the similarities and differences of structural features within and between groups of organisms
Investigate how organisms in an Australian habitat are adapted to their environment and document findings in a written scientific report
Interpret dichotomous keys to identify organisms surveyed in an Australian habitat
Explain how plants and animals are classified in Aboriginal and Torres Strait Islander Cultures based on their uses, forms and functions
Cells and classification in context
Research an organism to explain its classification and describe how it embodies all the characteristics shared by living things