characteristics of living organisms
Give two examples of living processes (life functions).
MRS GREN: Movement, Respiration, Sensitivity, Growth, Reproduction, Excretion, and Nutrition.
[Microscope] what is the name of the view you see when examining a specimen?
Name one organelle found only in plant cells.
Chloroplast, cell wall, or large vacuole.
What is a stem cell?
An unspecialized cell that can become any type of specialized cell.
A heart is made of muscle tissue. Which level of organization does “heart” represent?
Organ
A seed begins to grow when watered. Which characteristic of life does this show?
Growth — it increases in size and develops new structures.
What are the three main parts of the cell theory?
1. All living things are made of cells
2. The cell is the basic unit of life
3.All cells come from pre-existing cells
What does the mitochondrion do?
What is meant by “cell differentiation”?
The process where a stem cell develops into a specialized cell with a specific function.
Put level of organization of life in order
Cell → Tissue → Organ → Organ system → Organism.
A student says “fire is alive because it moves and grows.” Explain why they are wrong.
Fire is not living because it does not have cells, cannot reproduce, and does not perform all MRS GREN life functions.
A scientist finds a new cell. How does the cell theory help them decide if it’s living?
If it’s made of cells, it’s living — the cell is the basic unit of life.
What is the main function of the Golgi apparatus?
It modifies, packages, and transports proteins and other substances in the cell.
Where are two places stem cells are found?
Explain how tissues form organs.
Similar cells form tissues, and different tissues combine to form an organ that performs a function.
[Microscope]List 3 rules for a perfect biological drawing.
Use pencil, clear labels, title, no shading, accurate scale/proportion.
You need to find the total magnification of a microscope with 10× eyepiece and 40× objective. What is it?
x400
Why do plant cells have a cell wall but animal cells don’t?
To give rigid structure and support for standing upright.
Why do multicellular organisms need stem cells?
To replace or make new types of cells during growth and repair.
Give an example of plant or human showing all levels of organization from cell to organism.
Cells (e.g. muscle cells/Palisade cell)
→ tissues (muscle tissue/Palisade mesophyll tissue)
→ organs (heart/leaf)
→ organ systems (circulatory system/shoot system) → organism (human/sunflower).
A doctor checks if a virus is alive. Use MRS GREN to justify your answer.
Viruses are not living: they don’t move, respire, grow, excrete, or feed on their own — they only reproduce inside host cells.
Explain how the cell theory connects to the idea that tissues can repair after injury.
New cells come from pre-existing cells by division — tissues heal through cell reproduction.
Compare organelles found in plant vs animal cells.
Plant cells: cell wall, chloroplasts, large vacuole. Animal cells: no cell wall/chloroplasts, small vacuoles.
Explain one benefit and one ethical issue of using stem cells in medicine.
repair damaged tissues or treat disease. Ethical issue: destroying embryos or cloning concerns.
Explain how damage to one cell type (like nerve cells) can affect the whole organism.
The system fails (signals stop) → body functions like movement or control are affected.