Cells and Transports (C2) Flashcards
revise
What is the function of the cell membrane?
Controls what enters and exits the cell.
What is the function of the cytoplasm
Is the fluid inside the cell where chemical reactions occur.
What is the function of the smooth endoplasmic reticulum
Produces lipids and detoxifies proteins
What is the function of the rough endoplasmic reticulum
Synthesises proteins and is covered in ribosomes
What is the function of ribosomes
They are the site of protein synthesis
What is the function of the cytoskeleton
Maintains cell shape and movement
What is the function of lysosomes
Contain digestive enzymes to break down waste
What is the function of the nucleus
Controls cell activities and stores DNA.
What is the function of the mitochondria
Site of cellular respiration (produces energy)
What is the function of Golgi Apparatus
Modifies and packages proteins for transport.
What is the function of microfilaments
Support and shape the cell
What is the function of flagella
Assist in movement (eg. sperm cell tails)
What is the function of centrioles
Organise microtubes during cell division.
What s the function of cytosol
Fluid part of the cytoplasm that supports cell structure and transports molecules
What is the function of vesicles
Transport, store or digest substances within the cell.
What is the fluid mosaic model
A model that describes the cell membrane as a flexible structure with a phospholipid bilayer, where hydrophilic heads face outward and hydrophobic tails face inward.
What is the function of carrier proteins
Bind to specific molecules and change shape to transport them across the cell membrane, sometimes requiring energy.
What is the function of channel proteins
Create tunnels in the cell membrane to allow molecules or ions to pass through passively.
What is transport in cells
The movement of substances into and out of the cell to maintain homeostasis
What is passive transport
The movement of molecules from high to low concentration without using energy (ATP)
What is simple diffusion (pt)
The movement of small, non-polar molecules (e.g., oxygen, CO₂) directly through the membrane.
What is facilitated diffusion (pt)
The movement of large or charged molecules through a channel or carrier protein.
What is osmosis (pt)
The diffusion of water molecules from high to low water concentration across a semi-permeable membrane.
What is active transport
The movement of molecules from low to high concentration using energy (ATP)
What is the role of carrier proteins in active transport?
Transport substances against their concentration gradient (e.g., sodium-potassium pump).
How does the mitochondria assist active transport
It provides ATP, the energy needed for active transport
What is vesicular transport
The movement of large substances into or out of the cell using vesicles
What is endocytosis?
The process of engulfing materials by wrapping the membrane around them.
What is phagocytosis?
A type of endocytosis known as “cell eating” (e.g., white blood cells engulf bacteria).
What is pinocytosis?
A type of endocytosis known as “cell drinking” (e.g., uptake of fluids).
What is exocytosis?
The process of expelling materials using vesicles (e.g., secretion of hormones, neurotransmitters).
Why do small cells have an advantage?
They have a larger surface area-to-volume ratio, allowing efficient exchange of materials.
What happens if a cell gets too big?
Its volume increases faster than its surface area, making it harder to supply nutrients and remove waste efficiently.
How can a large cell adapt?
It can either divide (mitosis) or flatten to increase its surface area.
Why must large organisms be multicellular?
A single cell cannot support a large, complex organism, so multiple cells can specialize in different functions for efficiency.
