bio test 1 Flashcards
osmosis
osmosis is the movement of water from a place where there’s more water to a place where there’s less water, through a special barrier (like a cell membrane).
example of passive transport
Diffusion – Oxygen moving from your lungs into your blood is a great example. Oxygen naturally spreads from areas where there’s a lot (lungs) to areas where there’s less (blood).
Osmosis – Water moving into a dried-out plant cell to rehydrate it is osmosis, a special type of passive transport.
ex of active transport
Sodium-Potassium Pump – In nerve cells, sodium (Na⁺) is pumped out, and potassium (K⁺) is pumped in, even though it’s against their natural flow. This helps send nerve signals.
Plasma Membrane
The plasma membrane (also called the cell membrane) is like the gatekeeper of a cell. It controls what goes in and out, keeping the cell safe and functioning properly.
Properties of plasma membrane
The plasma membrane acts like a security guard, controlling what enters and leaves the cell.
It keeps harmful substances out while allowing essential nutrients to come in.
It also helps cells communicate with each other.
The plasma membrane is made of two layers of fat-like molecules called phospholipids.
Each phospholipid has two parts:
Head (hydrophilic = loves water) 🧡 – Faces outward towards water.
Tails (hydrophobic = hates water) 🖤 – Stays inside, away from water.
Because of this special structure, only certain substances (like oxygen and carbon dioxide) can easily pass through, while others need proteins to help them.
Thermodynamics
A branch of chemistry concerned with energy changes.
Kinetic energy
energy in motion
Potential energy
energy stored
oxidation
When an atom or molecule loses an electron
Reduction
When an atom or molecule gains and electron
1st Law of Thermodynamics
Energy can’t be created or destroyed. It can only be transformed.
2nd Law of Thermodynamics
Energy naturally spreads out, and systems become more disordered over time unless energy is added.
Entropy (disorder) always increases in a closed system, meaning things tend to break down or lose organization over time.
Enthalpy
A measure of energy in a thermodynamic system or the heat content of a system.
entropy
A state of disorder in thermodynamics.
enzyme
A protein that speeds up chemical reactions in the body
how do enzymes work
Enzymes work by binding to specific molecules called substrates at a designated site on the enzyme called the active site
competitive inhibitors
A substrate that competes with other substrates for control of the active site.
Noncompetitive Inhibitor
A substrate that does not bind at the active site but binds at a different site instead
Causes shape changes that makes the enzyme unable to bind to the substrate.
Allosteric Enzyme
Allosteric enzymes have a special “control switch” where molecules can turn them on or off.
They help the body regulate chemical reactions by speeding them up or slowing them down.
difference between cilia and flagella
Cilia are short, hair-like structures found in large numbers on a cell surface, while
flagella are longer, thread-like structures usually present in smaller numbers on a cell
Ribosomes
A type of organelle that is the site of protein synthesis.
Rough Endoplasmic Reticulum (Rough ER)
A type of organelle that is a network of membranes in the shape of flattened sacs, it also contains ribosomes.
Smooth Endoplasmic Reticulum (Smooth ER)
A type of organelle that is a network of membranes in the shape of tubules, it does not contain ribosomes.
Golgi Complex
An organelle that consists of 3-20 flattened, membranous sacs called cisternae.
It also Modifies, sorts, and packages proteins for transport to different destinations.
Lysosomes
A type of organelle that has vesicles that form from the Golgi complex and contains powerful digestive enzymes
Peroxisomes
Another type of organelle.
They are smaller than Lysosomes and are primarily found in the liver.
It Detoxifies several toxic substances such as alcohol
Track progress
Proteasomes
Proteasomes act like protein shredders, breaking down old or damaged proteins.
They help keep the cell clean and recycle useful protein parts. 🔄✨
Mitochondria
Obviously an organelle
Its the powerhouse of the cell.
It is extremely important because it generates ATP
Track progress
Nucleus
Also an organelle
Contains the chromosomes. This is where RNA is made from the DNA in the chromosomes.
passive transport
A Form of transportation that uses no energy
*High Concentration to low concentration
*Out to in
Diffusion
The passive spread of particles through random motion, from areas of high concentration to area of low concentration.
