Anatomy of the Cell Flashcards
Cellular Anatomy
All cells share general structures All cells have three main region -Nucleus -Cytoplasm -Plasma membrane
Plasma membrane and Membrane Transport
Phospholipid - special type of fat /lypid
polar head group that’s able to dissolve in water
two fatty acid tails
Embedded in the plasma membrane, Protein: serve as receptors, some are channels (passage way), signaling functions
Cytoskeleton: Give structure to the cell
Cholesterol in plasma membrane: Gives structure and stability.
Gycoprotein: Protein with sugar - make the cell sticky help the cell attached to whatever it needs too attached to. Signaling cells to help identify the type of cell each other are
3 Functions of Plasma Membrane
- Separate the cell with inside and outside cell (barrier)
- Regulate which things are able to pass inside and out
- Communication/Adhesion
Membrane Transport
Diffusion: Molecules want to move from high to low concentration
For ex, food coloring drop to glass of water. All those molecules will diffuse out so they’re in the same concentration
The plasma membrane serves as a barrier to diffusion for many molecules. Any molecules that dissolves in water won’t be able to pass through the non polar plasma membrane.
- Passive Transport - no energy required
- Active Transport - require energy
Types of Passive Transport -Simple Diffusion
Molecules lipid soluble molecules passing through the plasma membrane. Gases and really small molecules ethanol can pass through. Anything polar won’t be able to move through
Types of Passive Transport: Facilitating Diffusion
- Water moving through the plasma membrane = Osmosis
- Channel
- Carrier
No energy required
Membrane Transport: Active Transport
ATP - Energy currency within the cell. Mitochondria are making to power the cell
-In order to move through the membrane, some substances must use ATP some situations you want to move low to high concentration so we use special proteins called “pumps” that move the molecules against their concentration towards the higher concentration.
Bulk Active Transport: Endocytosis
Endo - bringing in
Bringing molecules into the cell - cyto
Molecules in extracellular space and the cell in engulfing them. Cell membrane will curl up around the particulars and form a structure (fat bubble) where there is a membrane surrounding some particles walling them off so the vesicle can move inside the cell
Requires ATP
Bulk Active Transport: Special type of Endocytosis
Phagocytosis “cell eating” - when we are ingesting specific large particles
What sort of cells or systems of the body might be involved with consuming and destroying foreign particles?
- Immune System
Macrophage - Type of immune cell that perform phagocytosis - cell consumes, starts the process of destroying particles them so pathogens can’t harm us.
Microglia - found in the nervous system residents in brain and spinal cord. Performs phagocytosis in the nervous system
Requires ATP
Bulk Active Transport: Exocytosis
Excyo - putting cells out
Small vesicles full within cells and fill them with molecules to be release
Requires ATP to release the all these molecules at once
Where in the body might you find cells that utilize exocytosis?
Glands areas that release hormones - pituitary gland (brain) adrenal gland and release to the blood supply.
Neuros - communicate with each other with small molecules called neurotransmitter - making vesicles of neurotransmitter then the vesicles will fuse with plasma membrane then neurotransmitter will be released to the extracellular space (Requires ATP)
Specialization of the Plasma Membrane
Microvilli - look like fingers - increase the surface area of our cell
Find them in cells within our small intestines. Bc those cells are bringing in nutrients we digested and want a lot of surface area to have those transporters have those enzymes to break down the particles to the smallest size and transporter to pull those in. If we had lower surface area greater risk, those particles would travel through our digestive system without being able to be absorbed
Has a lot cytoskeleton Actin
Specialization of the Plasma Membrane:
Cicilia, similar to microvilli - but bigger than microvilli.
- All different sizes some are longer and shorter. They have motor proteins within them filled with cytoskeleton proteins called microtubules which are able to generate movement.
- Move things along the surface of the cell but not for increasing surface area. Uses ATP.
- Found within in Respiratory tract, moving mucus and particles out of lungs.
Special type of cilia - Flagellum - found in tail of sperm, larger, has microtubules, motor proteins
Parts of the cell: Cytoplasm
Materials outside the nucleus and inside the plasma membrane.
4 Elements
-Cytosol - Fluid/gel due to salts, sugar and proteins dissolved in it. (Chemical reactions take place)
-Cytoskeleton - Support structure, constantly rearrange itself and move
-Inclusions - Areas within the cytoplasm that contain one type of molecule that cant dissolve in cytosol, like (pigments, large sugars, lipids)
-Organelles - our cells have mini organs to perform different functions for them
Parts of the cell: Cytoplasm - Cytoskeleton proteins
Actin/Microfilaments - smallest type of cytoskeleton
-sits underneath the surface of the plasma membrane, some superficial structural ability “dry wall of cell”
Intermediate filaments - Fibrous - “large metal beams/support” “structural stability” able to connect different cells and strongest
Microtubules - “train tracks” central hub within the cell job is for movement, dynamic (can increase/decrease in length)
Parts of the cell: Cytoplasm - Cytoplasmic Inclusions
Components in the cytosol that cannot be dissolved
-Lipid droplets - fat “dark”
-Glycosomes - very large and branch so many sugar molecules and can’t dissolve in water so the cell with sequester these glycogen to litter areas. proteins (enzymes) that will be able to breakdown the glycogen and release those individual sugar molecules.
Melanin - primary pigment in body
Glyco - sugar
cluster of sugars - most of cells don’t store glycogen the only places we see it are our liver and muscle cells
Part of the cell: Nucleus
Contains DNA (chromatin) wrapping the DNA around the balls of protein called histones "blueprint for all the proteins in our body" -Proteins are enzymes, transporters, channels serve all the channels that allow our cell to run
Blueprint for the proteins are contained in our gene.
Damage blueprints will be non functional, alter functions or cause problems in the cell
Nuclear envelope: Double phospholipid bi layer to protect the nucleus
- nuclear pores span both of the bilayers to get in or out.
Nucleolus - dense region, find RrNA, Ribosome making new proteins
Central Dogma
Transcription DNA serves as our blueprint and in order to go to proteins we make a copy of the blueprint called RNA (single straded) “translation” used to make protein
Constantly making proteins from our DNA. If we made proteins directly from DNA overtime, the DNA will get damaged and the proteins we make will have matuations and not function the same way. Which could lead to cancer.
Analogy cookie take original recipe and make a photo copy of the recipe
Parts of cell: Organelles
Ribosome - Sites of protein synthesis which can be found free in cytoplasm or attached to endoplasmic reticulum
- Do not have a lipid bilayer
- 2 Subunits
- Only consist of mRNA and proteins
Copy of DNA the message mRNA that comes in and the ribosomes will be reading this code within the MRNA and based on the code trRNA and will add another amino acid and the amino acid will be leaked together into a peptide chain.
