Jessicas Chapter 4-5 Notecards Flashcards
Using the term surface-area-to-volume-ration, explain why the vast majority of cells are small?
A cell needs a surface that is large enough to let nutrients in and let accumulating toxins out.( determines the size) Large cells would have to much going on inside compared to the surface area exchange.
What are the three statements that make up Cell Theory?
- All organisms are composed of cells 2. Cells are the basic unit of structure and function in organisms 3. Cells come only from pre existing cells (self-reproducing)
What shape is bacillus?
Rod-shaped
What is the shape of coccus?
Spherical
What is the shape of spirochete?
long, twisted rod-shapes
What are the three parts of the cell envelope?
Inside-outside plasma membrane, cell wall, and glycocalyx
Describe the first part of cell envelope.
Plasma membrane- regulates entrance and exit of substances to and from the cytoplasm (water based matrix inside the cell).
Describe the second part of cell envelope.
Cell wall- made of peptidoglycan and provides structure that is strong enough to resist cell swelling when water enters the cell.
The third part of cell envelope.
Glycocalyx(carbohydrate)-helps keep water in the cell, and an organized glycocalyx called a capsule protects some bacteria from a host immune system.
What is the difference between flagella and fimbriae?
Flagella- comparatively long appendages
Fimbriae- comparatively short appendages
Describe the function of a conjugation pili.
The appendage is a rigid tube used to pass DNA from cell to cell.
How do bacteria reproduce?
Split into two cells by binary fission
Is the conjugation pili involved in bacterial reproduction?
No. While it does pass on genetic info to other bacteria, it is not for the purpose of replication
Where is genetic information of prokaryote found in the cell?
In the cytoplasm. The Dna is coiled and forms a nucleoid which is not membrane bound
Describe the bacterial chromosome.
It’s DNA of a single-circular molecule. It forms the nucleiod.
How is bacterial chromosome different from a plasmid?
Bacterial chromosome- molecule of circular DNA
Plasmid-cell that can replicate chromosomes, like bacterial chromosomes
Are Cyanobacteria producers or consumers? How can you tell?
Producers because they are capable of photosynthesis like eukaryotic plants.
What do cyanobacteria use thylakoid membranes for?
To convert energy of the sun to energy containing bonds in organic molecules.
What two things are found in thylakoid membranes?
Chlorophyll and other pigments
Describe the changes that would have produced a membrane-bound nucleus. (Eukaryotic)
Eukaryotic cells were prokaryotes until they evolved from the invagination of the plasma membrane.
Describe the endosymbiotic theory of the changes that would produce a photosynthetic eukaryotic cell.
Eukaryotic cell engulfed cyanobacteria and instead of killing them, began using the products of cellular respiration for their metabolism.
Describe the endosymbiotic theory of the changes that would produce a eukaryotic cell able to use sugar and oxygen to create energy rich molecules (ATP).
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How are ribosomes different in prokaryotes compared to eukaryotes? Explain how this difference supports the endosymbiotic theory
Eukaryotes have larger ribosomes and found in the nucleolus in the nucleus where as prokaryotes are smaller and can be found in the cytoplasm
Chloroplasts and mitochondria are double membrane-bound organelles. Explain how this supports the endosymbiotic theory
Chloroplasts are the same size as cyanobacteria and mitochondria is the same size as heterotrophic bacteria. Both have a double membrane: one layer from the eukaryotes plasma membrane and one layer from the bacterias plasma membrane. Both have ribosomes that are the same size as bacterial ribosomes.
Characteristics and function in an eukaryotic cell: nucleus.
- Command center of the cell.
- large organelle
- nucleoplasm is the semi fluid matrix in the nucleus
- contains chromatin( nucleic acid DNA with proteins to organize)
Characteristics and function in an eukaryotic cell: nucleolus
Produces subunits of ribosomes
Characteristics and function in an eukaryotic cell: ribosomes
- Protein synthesis occurs in the cytoplasm, so ribosomes have to move through to do their jobs
- large and small subunits constructed in the nucleolus in the nucleus
- made of rRNA and some proteins
Characteristics and function in an eukaryotic cell: rough er
Studded with ribosomes that synthesize proteins
Characteristics and function in an eukaryotic cell: smooth er
Lacks ribosomes, synthesizes lipid molecules
Characteristics and function in an eukaryotic cell: Golgi apparatus
- Processes,packages, and secretes modified proteins
- Transports to the plasma membrane and other places in the cytoplasm like lysosomes.
- 3-20 flattened saccules
Characteristics and function in an eukaryotic cell: lysosomes.
- Vesicles that bud off the trans face of the Golgi apparatus.
- It assists in the digestion of cellular materials.
- Lysosomes can fuse with vesicles containing material from outside the cell and digest the material.
Characteristics and function in an eukaryotic cell: peroxisomes(micro bodies)
-Peroxisomes break down hydrogen period ideal it won’t damage the cell.
-Liver cells that need to convert fatty acid to glucose for cell
Plants: germinating seeds need to convert fatty acids to glucose for cellular reparation
Characteristics and function in an eukaryotic cell: mitochondria
Organelle that carries out cellular respiration, and produces ATP.
Double membrane:
- matrix: inside the inner membrane that has its own ribosomes and DNA
- inner membrane is folded into cristae
Characteristics and function in an eukaryotic cell: centrosomes
Microtubule organizing center that contains a pair of centrioles
What are two additional organelles found in a plant cell? What are their function and characteristics?
Central vacuole: filled with a water solution call cell sap. It takes up 90% of cytoplasmic space. And provides support and structure to the plant cell.
Chloroplast: contains the membranes, enzymes, and pigments for photosynthesis. It has a double membrane. It has thylakoids that are disk shape. Grana is a stacks of thylakoids and stroma is the water solution inside the chloroplast.