Biology - Module 1 & 2 Flashcards
Cells as the Basis of life
What are Prokaryotic Cells?
A prokaryote is a single-cell organism whose cell lacks a nucleus and other membrane-bound organelles.
What are Eukaryotic Cells?
A Eukaryotic organism whose cells have a membrane-bound nucleus. All animals, plants, fungi, and many unicellular organisms are eukaryotes.
What is simple diffusion?
the process in which solutes are passed through the concentration plain in a solution across a semipermeable membrane.
What is facilitated diffusion?
Facilitated diffusion is the process of passive transport of molecules or ions across a biological membrane through specific membrane proteins.
What is Osmosis?
Osmosis is the movement of water through a special membrane from an area where there’s more water to an area where there’s less water, helping balance the concentration of solutes on both sides.
What is the difference between Hypertonic, Isotonic, Hypotonic cells?
Hypertonic: Cells that lack water, shrivelled cells.
Animal - Crenated
Plant - Cytoplasm shrinks from cell wall
Isotonic: Cells that are balanced, correct amount of nutrients.
Animal - Normal
Plant - Flaccid
Hypotonic: Cells with too much water, swelling or burst.
Animal - Lysed
Plant - Turgid
What is Active Transport?
Active transport is when cells use energy to move molecules from a place where there are fewer of them to a place where there are more.
What is Endocytosis?
Endocytosis is when a cell wraps its membrane around something outside and pulls it inside to form a small bubble.
What is Exocytosis?
Exocytosis is when a cell pushes things out by packaging them in a bubble and then merging that bubble with the cell’s outer layer.
Explain the Surface Area to Volume ratio.
The surface area to volume ratio indicates how well a cell can exchange materials. A higher ratio means better efficiency, relative to their volume.
A small cube cell: Side length of 1 unit.
Surface Area = 6 sides × (1 unit × 1 unit) = 6 square units.
Volume = 1 unit × 1 unit × 1 unit = 1 cubic unit.
Surface Area to Volume Ratio = 6 / 1 = 6.
A larger cube cell: Side length of 2 units.
Surface Area = 6 sides × (2 units × 2 units) = 24 square units.
Volume = 2 units × 2 units × 2 units = 8 cubic units.
Surface Area to Volume Ratio = 24 / 8 = 3.
What are the inorganic nutrients that a cell requires?
Water
Gases (Oxygen and Carbon Dioxide)
Mineral salts (chlorides, nitrates, phosphates of sodium, magnesium, calcium, potassium etc.)
What are the organic nutrients that a cell requires?
Lipids - fats
Proteins - amino acids
Carbohydrates - starch
Nucleic Acid - DNA
What are Carbohydrates?
Carbohydrates are sugars and starches that provide energy.
e.g. Glucose, Fructose, Sucrose
What are Proteins?
Proteins are building blocks for the body. They help repair tissues, make enzymes and hormones.
e.g. Amino acids
What are Lipids? (3) provide example
- Lipids make up cell membranes and provide energy storage.
- They help maintain the structure of the cell membrane
- and protect internal components.
e.g. Glycerol - Fatty acid
What are Nucleic Acids?
Molecules that store and transfer genetic information.
e.g. DNA (genetic blueprint) RNA (protein synthesis)
What is the function of the Cell Membrane?
Structure (phospholipid bilayer), functions (selective permeability, transport).
Nucleus Structure?
Contains genetic material, controls cell activities.
Mitochondria Structure?
Site of cellular respiration, energy production.
What are Chloroplasts?
(In plants) Site of photosynthesis.
What is the Endoplasmic Reticulum?
Rough (with ribosomes) and smooth (lipid synthesis).
What is inside the Golgi Apparatus?
Modifies, sorts, and packages proteins and lipids.
Ribosomes?
Protein synthesis.
What is the function of Lysosomes?
Digestion and waste removal.
What is the purpose of the Cytoskeleton?
Provides structural support and shape.
Describe the Fluid Mosaic Model
Cell membrane as a fluid combination of lipids, proteins, and carbohydrates.
What do Glycolysis do?
Breakdown of glucose to pyruvate.
What is the purpose of the Krebs Cycle?
Production of electron carriers.
What does the Electron Transport Chain create?
Generates ATP.
Light Reactions to ______ ______
Conversion of light energy to chemical energy.
Simply give a definition to the Calvin Cycle
Fixation of carbon dioxide into glucose.
Mitosis:
Stages: P_______, M________, A_______, T_______.
Purpose: G_____, R____, S_____ R_________.
Mitosis:
Stages: Prophase, Metaphase, Anaphase, Telophase.
Purpose: Growth, Repair, and Asexual Reproduction.
Meiosis:
Stages: M_____ ? and ??.
Purpose: Production of g______ (s_____ and e___) for s_____ r_________, g______ variation.
Meiosis:
Stages: Meiosis I and II.
Purpose: Production of gametes (sperm and eggs) for sexual reproduction, genetic variation.
Types of Specialised Cells?
Neurons, muscle cells, red blood cells, etc.
What is Cell Differentiation?
Process by which cells become specialised for different functions.
The term Microscopy?
how to prepare and observe samples, using light or electron microscopes
How does Cell Staining work?
Enhances visualisation of cell structures.
