Cells Flashcards
What are cells?
Cells are the biological units that are the building blocks of life
State the cell theory
The cell theory states: “all living things are composed of one or more cells and all cells come from pre-existing cells”
How many millimetre make a micron?
1mm = 1000um
What is the equation to convert millimetres into microns?
a x 10^-3
What are the two different types of cells?
Eukaryotes
Prokaryotes
What are eukaryotes?
Cell with a nucleus and defined membrane and other organelles
Eg. Animals and plants
What are prokaryotes?
Without a nucleus, doesn’t have clearly defined components
Eg. Monera (bacteria)
What are the 14 main organelles in a eukaryotes cell?
Cell membrane Cytoskeleton Cytoplasm Nucleus Ribosomes Endoplasmic reticulum (smooth and rough) Golgi body Vesicles Lysosomes Mitochondria Centrioles
Plant organelles:
Cell wall
Chloroplast
Vacuole
What are the 10 main organelles of a prokaryotic cell?
Capsule Cell wall Plasma membrane Bacterial flagellum Ribosomes Chromosomes (DNA) Pili Plasmid (DNA) Nucleoid (nuclear zone/cytoplasm) Mesosome
What is the difference between prokaryotic cells and eukaryotic cells?
Prokaryotic cells experience difficulty performing several different functions at the same time, due to their lack of membrane-bound organelles, this limits their versatility. And a lack of a nuclear membrane
Eukaryotic cells have membrane-bound organelles in seperate compartments.
What is the job of cell membrane?
It acts like the border security, It is a semi-permeable membrane, that allows only certain substances in and out
What is the cell membrane made out of?
Lipids and proteins
Describe how the phospholipids work
They have two parts, a hydrophilic head (water loving) and a hydrophobic tail (water-fearing). Because of this arrangement it creates a two layer structure, as water surrounded the cell, it is a called a phospholipid bilayer.
What do proteins do in a cell membrane?
They can act like channels, signal receptors, or like the border security only letting certain things in and out. Some can just be found stuck on the side
What is the nuclear membrane?
It is a double layered membrane that has pores to allow substances in and out.
Molecules are constantly changing positions so it is fluid
What is the cytosol?
The semi fluid substance in the cytoplasm
What is the job of the nucleus?
It acts as the Brain.
It houses the cells genetic material (DNA)
It is made up of a nuclear envelope and nucleolus
What is the job of the cytoskeleton?
It acts as the skeleton of the cell. 💀
It helps maintain the cell’s shape, it is attached the cell membrane and holds the organelles in position. It constrains threadlike microfilaments and microtubules, and intermediate filaments.
What is the nucleolus?
A dark spot inside the nucleus, that creates ribosomes.