Ch.2 Cell Components & Functions Flashcards
State approximately how many cells are in a typical human body
37.2 trillion cells
Describe the major components described by the fluid mosaic model of the plasma membrane
Phospholipid Bilayer: Flexible outer layer
Proteins: Various functions and positions in the layer
Cholesterol: Stabilizes and maintains fluidity
Carbohydrates: Involved in cell recognition and signaling
Describe how the structure of phospholipids and their arrangements in a plasma membrane
Phospholipids have water-loving heads and water-repelling tails.
Phospholipids form a double layer with heads facing outwards and tails facing inwards, creating a flexible barrier
Describe the functions of plasma membranes
Controls what goes in and out of the cell, protects it, supports its shape, and enables communication with other cells
Describe the function of the nucleus
It’s the cell’s control center, aka it tells the cell what to do and when to do it
Describe the location and function of the nucleolus
The nucleolus is inside the nucleus. Its main job is to make ribosomes, which are the cell’s protein factories
Compare and contrast the structural and functional features of rough and smooth endoplasmic reticulum
Rough (ER) has ribosomes on its surface, giving it a “rough” appearance and makes and processes proteins
Smooth (ER) lacks ribosomes, so it looks “smooth.” and Produces lipids (fats)
Describe the functions of the Golgi Apparatus
Modifies, sorts, and packages proteins and lipids from the rough endoplasmic reticulum
Describe how The Golgi Apparatus relates to both vesicles and the rough endoplasmic reticulum
Vesicles are small sacs that transport these molecules between the ER and the Golgi and from the Golgi to other parts of the cell
Describe the functions of mitochondria
Mitochondria are the cell’s powerhouses. They produce energy by converting nutrients into ATP, which cells use for various activities
Which essential cellular processes occur within mitochondria
Cellular respiration happens inside the mitochondria
Describe the functions of lysosomes
They break down waste materials and old cell parts
Where are lysosomes made
They are made in the Golgi Apparatus
Describe the functions of peroxisomes
They help detoxify harmful substances in the cell, like breaking down fatty acids and neutralizing free radicals
Describe the function of ribosomes
They make proteins by reading genetic instructions and linking amino acids together
Describe the 2 biomolecules that make up ribosomes
Proteins: Give structure and do various jobs in the cell.
Ribosomal RNA (rRNA): Helps build proteins by reading the genetic instructions.
Diagram the process of protein synthesis
DNA → mRNA: DNA makes a copy of its instructions as mRNA in the nucleus.
mRNA → Ribosomes: mRNA travels to ribosomes, which read it and build proteins.
Protein → Golgi Apparatus: The newly made protein is sent to the Golgi Apparatus for final adjustments and packaging.
List the essential molecules involved in protein synthesis
DNA
mRNA:
Ribosomes.
tRNA
Amino Acids
Golgi Apparatus:
Define genome
The complete set of genetic instructions in an organism, including all its DNA
Define chromosome
A long, thread-like structure made of DNA and proteins that carries genetic information
Define gene
A segment of DNA that contains instructions for making a specific protein or trait
Define codon
A set of three DNA or RNA letters that codes for a specific amino acid or a stop signal in protein synthesis
Define sense codon
A set of three RNA letters that specifies which amino acid should be added next in a protein
Define start codon
Specific set of three RNA letters (AUG) that signals the beginning of protein synthesis
