Structure of Eukaryotic Cell Flashcards
What are the 7 key principles that make up Cell Theory of Biology?
- All living things are made up of cells
- Cells are the smallest unit of life
- Cells come from other cells
- The activity of the organism depends on the total activity of independent cells
- Energy flow occurs within all cells
- Cells contain DNA
- Cells are basically the same in chemical composition in organsims of similar species
All life forms are made from cells. What are the “biological building blocks of life” from smallest to largest?
Unicellular Multicellular - Cells eg muscle cell - Tissues eg cardiac muscle - Organs eg heart - Organ system eg circulatory system - Organism eg mammal
Cells arise from pre-existing cells. What are some of the ways this can occur?
Mitosis = parent cell divides into two identical daughter cells)
Meiosis = reduces number of chromosomes in the parent cell by half to produce 4 gamete cells
Binary fission = asexual reproduction by a separation of the body into two new bodies
What are the universal features of cells?
Plasma membrane Genome Information transfer Energy utilisation Cytoplasm
What is the plasma membrane?
- Selective barrier to segregate the cell form the environment
- Made up of a phospholipid bilayer
- Used for protein transport
- Surface area versus volume
What is a genome?
Hereditary information, codes for all cellular structures
Consists of DNA, histones, and chromatin
What is information transfer?
Ribosomes
The use of RNA in the formation of 50+ different kinds of proteins
What’s an example of energy utilisation?
Harnessing of energy to build more complex components
Metabolism = catabolism + anabolism
What is cytoplasm?
Semi-fluid, jelly-like
Embeds cellular components
What are the domains of life base cell types?
Bacteria (prokaryote)
Archea (Prokaryote)
Eukaryote
What is a nucleus?
Control centre
Structure = DNA, RNA, nucleolus, nuclear envelope, nuclear pores
What is endoplasmic reticulum (ER)?
- An assembly line for protein and lipid synthesis
- Detoxification
- Structure = network of sacs
What is the fucntion of the endoplasmic reticulum?
Rough ER = protein and ribosomes
Smooth ER = Lipids
Smooth + rough ER = continuous Ca2+ uptake/release
What is the golgi apparatus?
Used for distribution and packaging of glycoproteins and polysaccharides
A stack of 4 - 10 discs covering three regions
What are the names and functions of the three regions of the golgi apparatus?
Cis region = receives proteins/lipids from ER
Medial region = protein and lipid modification and maturation (glycosylation)
Trans region = glycoprotein and polysaccharides distribution via vesicles
What are lyosomes?
The cleaning crew or intracellular recycling
They are membrane bound vesicles containing 40+ digestive enzymes
What is the purpose and function of the mitochondria?
Powerhouse of a cell = source of energy production
(sugar + O2 = ATP + CO2 + H2O)
It has a double membrane (Outer = porin, Inner = electon transport)
Inside is the matrix = mixture of hundreds of enzymes, citric acid cycles, mtDNA, ribosomes, and tRNAs
What is the form and function of the cytoskeleton?
Made up of microtubules, microfilaments, and intermediate filaments
Structures that help maintain cell shape and internal organisation
Also provide mechanical support that enables cells to carry out essential functions like division and movement
What cell structures are unique to eukaryotes and which are unique to prokaryotes?
Eukaryote = nucleus, membrane organelles (ER, golgi apparatus, mitochondria, lysosomes, vesicles, etc), and cytoskeleton
Prokaryotes have a cell wall.
Describe the evolution of eukaryotes with example
Eukaryotes are larger and more complex than prokaryotes, so it is likely they were prokaryotes that engulfed other prokaryotes and entered into endosymbiosis
Endosymbiosis = one provides the other cell with energy and receives protection and nourishment
Mitochondria is an example as it has evolved to hold its own DNA and creat eits own energy and is passed down from mother to mother to mother
