Unit 3 Lesson 3 Structures of the Cell Flashcards
What is a cell and what is it associated with
a cell is the smallest unit that has all of the characteristics associated with life, including responding to stimuli; maintaining homeostasis; having a metabolism; having DNA; being capable of reproducing, evolving, and adapting; and growing and developing over time.
What is the exact defintion of an organlles
a small structure inside a cell that performs a specific function
The structures that perform specific functions within the cell are known as
organelles
What do cells do
A cell acts like a tiny factory, breaking apart nutrients to make energy and build proteins.
What are the structures inside a cell responsible for
Structures inside 0f the cell are responsible for making, changing, and moving proteins around the cell and to other parts of the body.
How many types of organelles are there
There are two types of organelles.
Describe the 2 types of organelles
There are organelles such as ribosomes and cell walls that are not covered by a membrane, and there are organelles such as nuclei and mitochondria that are surrounded by at least one membrane similar to the cell membrane.
What are membrane-bound organlles
an organelle that is surrounded by a lipid bilayer similar to the cell membrane
The presence of membrane-bound organelles separates cells into two types:
prokaryotes and eukaryotes.
What are prokaryotic cells?
A type of cell, usch as bascteria and archaea cells, that does not contain membrane-bound organelles; Prokaryotic cells, such as bacteria and archaea, are cells that lack membrane-bound organelles.
What are Eukaryotic cells
A type of animal or plant cell that contains membrane-bound organelles, such as nucleus; Eukaryotic cells, such as animal and plant cells, are cells that have membrane-bound organelles.
What organisms are made up of eukaryotic cells
All multicellular organisms, such as animals and plants, are made of eukaryotic cells.
What do eukaryotic cells contain
These cells have membrane-bound organelles such as nuclei and mitochondria.
What do eukarytoic cells allow cells to do? Something that is not easily accomplished by prokarytoic cells and gives eukaryoic cells a distinct advatnafe
These organelles allow the cells to separate spaces within the cell chemically, allowing them to perform functions that are not easily accomplished by prokaryotic cells.This gives eukaryotic cells a distinct advantage. These organelles have allowed eukaryotic cells to become extremely diverse in form and function
How are plant and animal cells similar
Other than a few structures, animal and plant cells are very similar. Their parts function in the same way, and they make proteins in the same way.
What is the importance of protein in cells in structures
Many proteins are used for structural materials in an organism, such as muscle, bone, channels through the cell membrane, and, in mammals, hair and fingernails
What are proteins respobile for organisim triat wise
Proteins are also responsible for an organism’s traits. The genetic material (DNA) inside a cell provides the blueprint needed to make all the traits of an organism. Once the proteins are made, different structures inside the cell called organelles move them to where they are needed.
Where is a eukaryotic cells gentic material (DNA stored)
A eukaryotic cell’s genetic material (DNA) is stored in an organelle called the nucleus.
What is the role of the nucleus
The nucleus serves as the control center for the cell, controlling all of its activities. The following electron micrograph shows an animal cell with its nucleus.
Protein synthesis involves two processes:
transcription and translation.
What is the exact meaning of transcription
he process by which RNA polymerase copies a segment of DNA into mRNA
Where does transcripton happen
in the nucleus of eukaryotic cells.
Where does transcription happen in prokaryotic cells?
In prokaryotic cells, which lack nuclei, this process happens in the cytoplasm.
What does transcritopn invole in both cell types
In both cell types, transcription involves the enzyme RNA polymerase using DNA as a template to create a messenger RNA (mRNA) molecule.
DNA has four nitrogen bases; what are they
DNA has four nitrogen bases – adenine (A), thymine (T), cytosine (C), and guanine (G).
What do the order of DNA nitrgrn bases dtermine
The order of these bases determines the order of amino acids in proteins.
What happens to mRNA in eukaryotic cells
In eukaryotic cells, the mRNA produced is transported from the nucleus to the cytoplasm.
In the cytoplasm what does the mRNA join with
In the cytoplasm, the mRNA joins with an organelle called a ribosome.
What are ribosomes
an organelle, found either free-floating in the cytoplasm or attached to the endoplasmic reticulum, where proteins are made
Where are ribosomes found
. These structures can be found either free-floating in the cytoplasm or attached to the endoplasmic reticulum.
What does Ribosome contain
Ribosomes contain both a small and a large subunit that are needed to complete protein synthesis.
What do the small and big subunits do in the mRNA
The small subunit reads and decodes the sequence of bases in the mRNA while the large subunit connects the amino acids together to make a protein.
Where are small subunit and large subunit located
The ribosome moves along the mRNA molecule with the small subunit underneath the mRNA and the large subunit above it.
The large subunit has 3 holes..
The large subunit has three holes that expose three portions of the mRNA molecule. Each of these three portions consist of three bases that are known as a codon.
What is a condon
a group of three bases in mRNA that codes for an amino acid in the protein
What does a codon do
A codon binds to a three-base pair segment on a transfer RNA (tRNA) molecule called an anticodon.
What is a anticodon
a group of three bases in tRNA that is complementary to a codon on mRNA
Why do codons speficy certain maino acids?
These tRNA molecules are attached to specific amino acids. This is why codons specify certain amino acids.
codons specify certain amino acids; give an example
For example, the codon A U G on an mRNA molecule would bind to the anticodon T A C. This tRNA molecule is attached to the amino acid Methionine, or Met. Just remember that in RNA, adenine (A) pairs with Uracil (U) and Guanine (G) pairs with Cytosine (C).
What is a translation
As the tRNA molecules come into the ribosome to pair with the codon, the large subunit binds the amino acids together using a peptide bond and detaches them from the tRNA. This creates a string of amino acids called a polypeptide, and the sequence of the amino acids matches the sequence specified by the codons on the mRNA. This process of producing protein from an mRNA is known as translation.
What is the exact meaning of translation
the process by which a ribosome produces protein based on the sequence of a mRNA
In the eukaryotic cells; what is the function of the rought endoplsamic reticulum organelle
has ribosomes on its surface; proteins made here are packaged directly into the cell membrane, into an organelle, or will be exported out of the cell
In the eukaryotic cells; what is the function of the smooth endoplasmic reticulum
organelle?
lacks ribosomes on its surface; not involved in protein synthesis; instead, this organelle makes lipids and steroids that will be used in the production of membranes and hormones, and it also functions in detoxification of waste materials
In the eukaryotic cells; what is the function of the Golgi apparatus organelle
modifies proteins that require specific attachments of sugars or lipids and packages proteins for export from the cell, integration into a cell membrane, or packaging into a specific organelle like a lysosome
In the eukaryotic cells; what is the function of the vesicles organelle
small membrane-bound organelles that shuttle proteins and other materials throughout the cell
What are factors that are aport of the endeomebran ssytem in eukaryotic cells
The nuclear envelope, rough endoplasmic reticulum (or rough ER), smooth endoplasmic reticulum (or smooth ER), Golgi apparatus, and vesicles are all part of the endomembrane system within eukaryotic cells.
What does the endomembrane sstem produce
This network of membrane-bound organelles produces a wide variety of proteins that will be used for membrane transport, hormonal signaling, communication, and many other functions.
What is the endomembrane system
a network of membrane-bound organelles that are involved in the production and processing of proteins that will be integrated into a membrane, packaged into an organelle, or exported to the outside of the cell
There are two types of ribosomes:
free ribosomes and ribosomes attached to the rough ER.
What is the function of the ribsomes that are attached to the endoplasmic reticulum
The ribosomes that are attached to the endoplasmic reticulum (ER) are where proteins are made that will be either inserted into a membrane, packaged into a specific organelle, or exported to the outside of the cell.
What happens to the rough ER in the Golgi apparatus
From the rough ER, the proteins are moved to the Golgi apparatus using membrane-bound organelles called vesicles. In the Golgi apparatus, the proteins are modified by attaching sugars or lipids to them, sorted, and exported to their final destination using more vesicles
What happens to the proteins in ribosomes
Some of those proteins will be exported from the cell, some will be integrated into membranes around the cell, and others will be packaged into specific organelles.
What does protein inhibotors
Protein inhibitors can slow or stop protein synthesis. Usually, these inhibitors stop the ribosome from decoding the genetic information correctly. Several prescription drugs affect how protein synthesis happens within the cells.
Several prescription drugs affect how protein synthesis happens within the cells. Give example
tetracycline is used to stop proteins within bacteria cells from growing. Tetracycline stops the tRNA from attaching to the bacteria’s ribosome and stops the bacteria from making proteins. Like tetracycline, other antimicrobial drugs have been made to control a large variety of infections including acne. These drugs sometimes stop working for patients when bacteria develop resistance to the current medication due to mutations, making the need for different protein inhibitors important.
Which types of proteins will move through the Golgi apparatus?
Proteins that will be inserted into a membrane, packaged into an organelle, or exported to the outside of the cell.
If a ribosome is making a protein that will be exported from the cell, to which membrane-bound organelle would it attach?
The rough endoplasmic reticulum.
Describe the differences between the rough and smooth endoplasmic reticula (ER).
Possible answer: The rough ER has ribosomes attached to it whereas the smooth ER does not. The rough ER is involved in the production and modification of proteins that will be integrated into a membrane, packaged into an organelle, or exported to the outside of the cell whereas the smooth ER is involved in the production of lipids and the detoxification of waste.
If a cell was unable to make vesicles, describe what would happen to protein synthesis.
The synthesis of proteins that function in the cytoplasm would be unaffected. However, proteins that are inserted into membranes, packaged into organelles, or exported to the outside of the cell would get stuck in the rough ER because the cell would not be able to produce vesicles to transport the proteins to the Golgi apparatus or its final destination inside or outside of the cell.
Hide
omplete the paragraph.
The…….has ribosomes attached to it. These ribosomes are the sites of ……. synthesis. Materials made on the rough ER are …. the ce
The rough ER has ribosomes attached to it. These ribosomes are the sites of protein synthesis. Materials made on the rough ER are inserted into the membrane, packaged into an organelle, or transported out of the cell.
Compare and contrast protein synthesis in eukaryotes versus prokaryotes.
Prokaryotes lack membrane-bound organelles like the nucleus. Because of this, transcription and translation happen in the same place. Once the mRNA is made during transcription, the ribosome can immediately bind to it and translate protein from it. This is not possible in eukaryotes because transcription happens inside the nucleus while translation happens on the ribosome in the cytoplasm.
