Chapter 3 Flashcards
Type of cells
Eukaryotic and prokaryotic cells
Organelles in eukaryotic cells
Mitochondion, Nucleus, Nucleolus, ROugh Endoplasmic Reticulum, Ribosome, Call surface membrane, Smooth Endoplasimc reticulum, Golgi appratus, Lysosome, Centrioles
Organelles in Procaryotic cells
Ribosome. circular DNA, cell surface membrane , cell wall , cytoplasm , flagellum , pili, capsule, plasmid, infoloding cell surface membrane
Common features between the cells of living organishms
Cell surface membrane, cytoplasm, DNA, ribosome
Function of mitochondria
It is the site of aerobic respiration within eukaryotic cells. IT is surrounded by a double membrane with the inner membraine folded to form structures called cristae. It produces ATP from respiration.
Function of Ribosome
It is the site of translation. Each ribosome is a complex of ribosomal RNA and proteins. 80s ribosomes are found in eukaryotic cells and 70s ribsomes are found in prokaryotes, mitochondra and chloroplasts
Two types of endoplasmic enticulum
The two types are : Rough Endoplasmic Reticulum (rER) and Smooth Endoplasmic Reticulum (sER)
Function of rER
rER is formed from fols of membrane contious with the nuclear envelope. The surface of rER is covered with ribsomes and the role of it is to process proteins made on the ribsomes
Function of sER
sER is also formed from folds of membrane but its function is distince from the rER, being involved in the production of processing and storage of lipids, carbohydrates and steriods. ( IT DOES NOT HAVE ANY RIBOSOMES ON THE SURFACE)
Function of the golgi appratus
It consists of flattened savs of membrane similar in apperance to the smooth endoplamic reticulum. The role of the Golgi appratus is to modify proteins and lipids before packagin them into golgi besicles. The vesicles then transport the proteins and lipis to their required destinations.
Funtion of lysosome
Lysosome are the specialist forms of vesicle which contain hydrolytic enzymes. The role of it is to break down wast materials such as worn out organelles.
Function of centrioles
Centroles are made of hollow fibers knows as microtubules. It is the filaments of protein that can be used to move substances around insie a cell as well as to support the shape of a cell from the inside. Two contrioles at right angles to each other form a centrosome which oraganises the spindle fibers during cell division ( THEY ARE NOT FOUND IN PLANTS OR FUNGI)
Organelles included in the process of protein synthesis
Nucleus ( transcription of the DNA code occurs here), ribsomes ( free ribsomes and those on the rER produce proteins in the process of translation, rER, Golgi appratus, Cell surface membrane ( proteins formed within the cell are secreted here)
Process of Protein synthesis
-The nucleolus manufacture ribsome for protein synthesis in the rER.
-The nucles manufacutes mRNA, which is needed by ribsomes to make proteins.
-The ribosomes in the rER make proteins.
-The rER processes the proteins which are then sent in vesicles to the golgi body
-The golgi body further processes the proteins and sends them in vesicles to the plasma membrane.
-The besicles fuse with the plasma membrane to secrete the finished protein product.
Differences between eukaryotic and prokaryotic cells
Plasmids, capsules, flagellum, pili, mesosomes
Description of plasmid
Small loops of DNA that are seperate from the main circular DNA molcules. Plamids contain genes that can be passed between prokaryotes. ( NOT PRESENT IN ALL PROKARYOTES)
Description of capsule
Dome prokaryotes are surrounded by a final outer layer knows as a capsule. This is sometimes called the slime capsule. It helps to protect bacteria from drying out and from attack ny cells of the immune system of the host organism. (NOT PRSENT IN ALL PROKARYOTES)
Description of flagellum
A long hair like structure that rotaes, enabling the prokaryote to move. Dome prokaryotes have more than one. (NOT PRSENT IN ALL PROKARYOTES)
Description of pili
Thread like structures on the surface of some bactera that enable the bacteria to attach to other cells or surfaces
Description of Mesosomes
Infolded regions in the plasma membrane of some prokaryotic cells. They have many fucntions including aerobic respiration, cell wall formation and DNA replication
Description of Circular DNA
The genetic material of prokaryotic cells mainly consists of a single circular strand of DNA that is not contrained in a membrane bound nucleus. The area in the prokaryotic cell where this circular DNA molcule is found is knows as the nucleiod.
Description of Ribosomes
Prokaryotic ribosome are 70s ribsomes and are smaller than the 80s ribosomes of eukaryotic cells. They are the site of protein synthesis in prokaryotic cells
The phases of cell cycle
Interphase. NUclear division ( mitosis), cell division ( cytokinesis)
Interphase phases
It consists of three phases : G1 phase, S phase, G2 phase
What happen during the three phases
During G1 phase, a signal is received telling the cell to divide again. The DNA in the nucleuse replicates resulting in each chromosome consisting of two identical sister chromatids.
During S (synthesis) phses, the cells make the RNA, enzymes and other proteins required for growth during the G1 phases.
During G2 phase, the cell continues to grown and the new DNA that has been synthesised is checked and any error are repaired.
What is cytokinesis
It is after mitosis phses. Once the nucleus has divided into two genetically identical nuclei, the whole cell divisdes and one nuclus moves into each cell to create two genetically identical daughter cells.
What is mitosis
It is the porcess of nuclear division by which two genetically identical daughter nuclei are produced that are also genetically identical to the parent cell nucleus.
What are the four stages of mitosis
Prophase, Metaphases , Anaphase , Telophase