What does cell theory state?
All living organisms are made up of cells and the products of cells, and cells come from pre-existing cells.
What is the unit of structure and function in all living organisms?
Cells.
What molecule is known as the molecule of heredity?
DNA.
What are the two major types of cells?
Eukaryotic and prokaryotic.
How do prokaryotic cells differ from eukaryotic cells?
Prokaryotic cells are smaller, less specialized, and do not contain membrane-bound organelles.
What process do prokaryotic cells use to divide?
Binary fission.
What are the four phases of mitosis?
- Prophase
- Metaphase
- Anaphase
- Telophase
What occurs during anaphase in mitosis?
Pairs of chromatids are separated and moved by the spindle to opposite poles of the cell.
What is the process of DNA replication used for?
To make an identical copy of the DNA prior to cell division.
What is the main energy requirement for all cells?
A form of energy for life’s processes such as movement, synthesis, and maintaining a stable internal environment.
What is photosynthesis?
The process by which autotrophs convert inorganic materials into organic molecules using light energy.
What do heterotrophs require for energy?
They need to feed on matter containing organic molecules.
Name three important chemical reactions involved in energy changes in organisms.
- Photosynthesis
- Aerobic respiration
- Fermentation
What is the function of the cell membrane?
It separates the internal environment of the cell from the external environment.
What is the structure of the cell membrane?
A phospholipid bilayer with embedded proteins.
What processes control the exchange of materials in and out of cells?
- Diffusion
- Osmosis
- Active transport
- Endocytosis
- Exocytosis
What type of transport occurs via diffusion and osmosis?
Passive transport.
What is required for active transport?
Energy.
What is the significance of surface area to volume (SA:VOL) ratio in cells?
It maximizes the rate of diffusion and exchange of materials.
What are the main groups of microorganisms?
- Bacteria
- Archaea
- Fungi
- Protists
- Algae
What conditions do bacteria generally grow best in?
- Temperature: 30-40°C
- pH: around 7.2-7.4
- Organic and inorganic materials
- Suitable water/solute balance
Why are microorganisms important to humans?
- Decomposers recycling matter
- Oxygen production by phytoplankton
- Recombinant DNA technology
- Culturing for food production
- Digestive system
Fill in the blank: Oxygen production by _______ accounts for approximately 50% of the total oxygen produced on Earth.
phytoplankton
