Cell Biology: Anatomy and Physiology 12 Intro

A set of vocabulary flashcards covering cell theory, prokaryotic vs. eukaryotic structures, and the functions of various organelles as described in the lecture notes.

Cell Theory

The core biological concept stating that cells are the smallest units of living things and all cells arise from preexisting cells.

Prokaryotic cells

Simplistic, usually unicellular organisms (like bacteria) that lack a nucleus and membrane-bound organelles.

Eukaryotic cells

Complex cells, including plant and animal cells, that contain a nucleus and specialized membrane-bound organelles such as mitochondria and the Golgi apparatus.

Plasma membrane

Also known as the cell membrane, it acts as a boundary made of two layers of phospholipids that controls what enters and exits the cell.

Permeable

A state where a membrane allows substances to move in and out freely.

Selectively permeable

A characteristic of the cell membrane where only specific substances are allowed to pass through while others are blocked.

Impermeable

A state where substances are completely unable to pass through a membrane.

Phospholipid bilayer

The two-layer structure of the cell membrane consisting of hydrophilic glycerol/phosphate heads and hydrophobic fatty acid tails.

Mitochondria

Known as the "powerhouse of the cell," this organelle is where cellular respiration occurs to produce ATP energy.

Cellular Respiration

The process where the cell uses glucose and oxygen to produce carbon dioxide, water, and ATP, represented by the equation $C_6H_{12}O_6 + 6O_2 \rightarrow 6CO_2 + 6H_2O + \text{ATP}$.

Cristae

The internal folds of the mitochondria where the actual process of cellular respiration takes place.

Matrix

The liquid part found inside the mitochondria.

Ribosomes

Organelles responsible for protein synthesis, specifically the stage known as translation.

Polyosomes

Clusters of many ribosomes working together to produce multiple copies of the same protein, such as insulin.

Smooth Endoplasmic Reticulum (SER)

An organelle lack ribosomes that synthesizes and transports lipids and steroids, and helps detoxify drugs and chemicals; it is abundant in the liver, testes, and ovaries.

Rough Endoplasmic Reticulum (RER)

An organelle studded with ribosomes that is involved in the initial modification and changing of proteins.

Golgi Apparatus

An organelle located further from the nucleus that modifies, packages, and sorts proteins received from the endoplasmic reticulum.

Vesicles

Small phospholipid-bound sacs used for storage and transporting materials like waste, water, or proteins throughout the cell.

Lysosome

A specific type of vesicle arising from the Golgi apparatus that contains hydrolytic enzymes used to break down dead organelles or ingested particles.

Hydrolytic enzymes

Proteins within lysosomes that degrade nucleic acids, lipids, and carbohydrates through the process of hydrolysis.

Phagosome

A vesicle containing ingested particles, like bacteria or viruses, that fuses with a lysosome for destruction.

Nucleus

The control center of the cell that holds DNA, monitors cell conditions, and is the site of DNA replication and transcription.

Nuclear envelope

A double phospholipid bilayer that surrounds the nucleus to protect the DNA and control the movement of materials through pores.

Transcription

The first part of protein synthesis that occurs within the nucleus where a gene copy (mRNA) is made.

Nucleolus

A dark spot located inside the nucleus responsible for the production of rRNA (ribosomal RNA).

Cytoplasm

A jelly-like substance composed of microtubules and microfilaments that gives the cell its shape and serves as the medium where organelles reside.