Biology review

Chloroplasts

Contain chlorophyll and enzymes that function in photosynthetic function of sugar

Smooth ER

A network of membranes involved in the synthesis of lipids and detoxification of drugs.

Nucleolus

A dense region within the nucleus responsible for ribosomal RNA synthesis and ribosome assembly.

Cell membrane

A semi-permeable barrier surrounding the cell, composed of a lipid bilayer that regulates the movement of substances in and out of the cell.

Intermediate filaments

Fibrous proteins that provide structural support to cells and help maintain cell shape by resisting tension (pull)

Lysosomes

Cell organelles that contain digestive enzymes for breaking down waste materials and cellular debris.

Golgi body

A cell organelle involved in modifying, sorting, and packaging proteins and lipids for secretion or delivery to other organelles.

Nucleus

The membrane-bound organelle that contains the cell's genetic material and controls cell growth, metabolism, and reproduction.

Rough ER

A type of endoplasmic reticulum studded with ribosomes, involved in protein synthesis and processing.

Microtubules

Cylindrical structures made of tubulin proteins, part of the cytoskeleton that provide structural support and facilitate intracellular transport.

Ribosomes

Cellular structures composed of ribosomal RNA and proteins, essential for synthesizing proteins by translating messenger RNA.

Secretory vesicles

Small membrane-bound sacs that transport proteins and other molecules to the cell membrane for secretion or to different organelles within the cell.

Central vacuole

A large, membrane-bound organelle found in plant cells, responsible for storing nutrients and waste products, and maintaining turgor pressure.

Cell wall

A rigid outer layer that provides structure and protection to plant cells, fungi, and certain bacteria, composed mainly of cellulose in plants.

Microfilaments

Thin, thread-like structures made of actin that are part of the cell's cytoskeleton, providing support and assisting in cellular movement.

Mitochondria

Double-membrane organelles known as the "powerhouses of the cell" because they generate ATP through cellular respiration.

Vesicles

Small membrane-bound sacs that transport materials within the cell, playing key roles in storage, secretion, and metabolism.

Endosymbiotic theory

The scientific explanation for the origin of mitochondria and chloroplasts, suggesting that these organelles evolved from free-living prokaryotic organisms that entered into a symbiotic relationship with ancestral eukaryotic cells.

Molecular motors

Proteins that facilitate movement within cells by converting chemical energy into mechanical work, often transporting cellular cargo along cytoskeletal filaments.

Ligands/signals

molecules that bind to receptors, triggering cellular responses.

Passive transport

The process by which substances move across cell membranes without the need for energy input, typically following their concentration gradient.

Facilitated diffusion

The process by which molecules pass across a cell membrane through protein channels, allowing for faster transport than simple diffusion.

Isotonic

a solution with the same concentration of solutes as another solution, resulting in no net movement of water across a membrane.

Phagocytosis

The process by which cells engulf large particles or other cells, forming a vesicle to internalize the material.

Receptors

proteins on cell surfaces that bind to signaling molecules and initiate a cellular response.

Osmosis

The movement of water molecules across a selectively permeable membrane from an area of lower solute concentration to an area of higher solute concentration.

Hypotonic

is a solution with a lower concentration of solutes compared to another solution, leading to water influx into cells.

Hormones

chemical messengers produced by glands that regulate physiological processes in the body.

Exocytosis

The process by which cells expel materials by enclosing them in a vesicle that fuses with the plasma membrane, releasing the contents outside the cell.

Active transport

is the movement of molecules across a cell membrane against their concentration gradient, requiring energy in the form of ATP.

SImple diffusion

is the movement of molecules across a cell membrane from an area of higher concentration to an area of lower concentration without the use of energy.

Hypertonic

solution that has a higher concentration of solutes compared to another solution, causing water to move out of a cell.

Endocytosis

is the process by which cells internalize substances by engulfing them in a vesicle, allowing for the uptake of large molecules or particles.

Virulent

describes a pathogen's ability to cause disease, often indicating the level of severity and infectivity.

Attachment/absorption

is the initial step in viral infection where the virus binds to a host cell surface receptor, facilitating entry into the cell.

penetration/entry

the process of a virus entering a host cell after binding to its surface receptors.

enveloped viruses

Viruses that have a lipid membrane surrounding their capsid, aiding in cell entry.

Bacteriophage/phage

A type of virus that infects and replicates within bacteria, often utilizing the bacterial machinery for reproduction.

Naked/non-enveloped

Viruses that lack a lipid membrane surrounding their capsid, making them more resistant to environmental conditions.

Lysogenic

A viral replication cycle where the virus integrates its genetic material into the host's genome, remaining dormant until an activation signal occurs.

Synthesis

The process by which a virus or cell produces new molecules, including proteins and nucleic acids, during replication.

Release

The final stage of the viral replication cycle where new viral particles exit the host cell, often destroying the cell in the process.

Viruses

Microscopic infectious agents that require a host cell to replicate and produce new virions.