Cell structure and function Flashcards
What are some features of the structure of prokaryotic cells
- cell wall
-flagellum - no nucleus( why they are pro and not eu karyotes)
- no membrane bound organelles
- asexual reproduction
- single circular chromosomes
What are some of the features of the structure of Eukaryotic cells
- Nucleus
- linear chromosomes
- sexual reproduction via meiosis
- membrane bound organelles
- cell membrane
What are cell organelles
specialised sub units with specific functions
What are some features of the nucleus
- nuclear envelope has 2 lipid bilayers
- contains genetic information (DNA)
- DNA for protein production
- membrane pores for transport
What are some features of the endoplasmic reticulum
- extensive network of fluid filled membranes
- half total membrane in eukaryotic cells
What is the function of the smooth ER
- high concentration of enzymes
- Diverse metabolic functions
. lipid synthesis
. metabolism of carbohydrates
. detoxification of drugs and poisons
. storage of calcium ions - hormone producing cells are rich in smooth ER
What is the function of the Rough ER
- studded with ribosomes for protein production
- protein folding and modification occurs here
- vesicles that contain protein bud off from this
What is the function of ribosomes
- float freely in the cytoplasm
- protein and rna structure
- site where proteins are made
What is the function of lysosomes
- processed in rough er and contain digestive enzymes to digest invading cells (phagocytosis)
- breakdown worn out components of the cell
What are the three types of cytoskeletons
-actin= cell structure, shape and movement
- microtubules= tracks for motor proteins
- intermediate = anchorage for organelles
What are motor proteins
- use microtubule as a track to transport cellular cargo e.g. organelles and proteins
- require energy in form of ATP
what is the structure and function of cilia and flagella
- structures beat to allow movement of fluid across cell surface, and in single cells enables them to swim e.g. sperm
- requires atp
What is the function of the mitochondria
- site of respiration which gives energy in the form of ATP
- proteins and enzymes built in to the inner membrane
What is cellular respiration
- conversion of energy from one form into another that can be used
- chemical process in which energy is released from the breakdown of glucose.
- the progressive oxidation of glucose to form energy that is in the form of ATP to support other cellular functions in the body
How does ATP release energy
Through a chemical breakdown with water( hydrolysis)
What is Glycolysis
- the break up of glucose taking place in the cytoplasm
- turns 6 carbon glucose into 2x 3 carbon pyruvate molecules
What is the purpose of the krebs cycle
Once glycolysis breaks glucose down to 3 carbon molecules, krebs transfers these to electron carries which can be used in the electron transport chain to produce ATP
What is NADH and FADH2
- NAD+ and FAD pick up electrons from one molecule and drop them off with another and carry electrons that have high energy down the steps
- provide electrons to electron transport chain
What is the electron transport chain
The series of four protein complexes that leads to the creation of ATP in a complete system named oxidative phosphorylation
What is anaerobic respiration
production of energy in the absense of oxygen, ignores krebs and converts pyruvate to lactate by NADH (lactic acid fermentation)
What are some functions of the cell membrane
- boundaries of cells and organelles (protection and support)
- hold process enzymes close in proximity
- permeable
- maintain homeostasis
- surface receptors ( proteins ) for cell signalling
What is passive transport
- susbstance moves from high concentration to low down a concentration gradient
What is phosphorylation
when a phosphate joins to an adp to make atp
What is osmosis
- movement of specifically water across a partially permeable membrane
- water moves to dilute a solute
What is active transport
- requires atp energy to transport molecules and ions up a concentration gradient which allows cells to maintain internal concentrations of solutes
