cell structure and function Flashcards
who discovered the cell wall and coined the term
Robert Hooke pioneered the field of microscopy. Published ‘Micrographic’ in 1664
what are three principles of cells theory
-cells are the smallest units of life
-all living things are made up of cells
-all cells come from pre-existing cells.
what are the smallest cells
prokaryotic cells. pro-kary- coming before.
what are some characteristic of Eukaryotic cells
microscopic. highly compartmentalized, nucleus. much more active and complex functions (metabolism, regulation etc.) they have a nucleus, plants and some fungi have cell walls
are plant cells eukaryotic
yes
what are some differences between plant and animal cells
plants cells have cells wall, and chloroplasts (photosynthesis).
what are the main components of a bacterial cell wall
bacterial cell walls are primarily made of peptidoglycan
how does penicillin work
penicillin in an antibiotic. It functions by damaging a bacteria’s cell wall by preventing the production of peptidoglycan, leaving the cell weak.
why are cells so small
cells are small because their size maximizes the surface area to volume ratio, allowing for efficient exchange of nutrients, waste, and other molecules.
this is because smaller cells can more easily take in/expel molecules compared to larger cells due to the larger relative surface area available for diffusion.
what are characteristics of prokaryotic cells
-no nucleus
-no mitochondria
no Golgi bodies
-no chloroplasts
-no lysosomes
-they have a cell wall
what are some characteristics of every cell?
-cytoplasm
-plasma membrane
-one or more chromosomes
-ribosomes
where is DNA stored in a cell without a nucleus
DNA is stored in a region called the nucleoid.
what is the difference between a cell membrane and a cell wall
- a cell wall is a rigid outer layer found in plants and some fungi and bacteria. It can be made of pectin, chitin, lignin, glycoproteins, glycolipids, and cellulose.
- a cell membrane is present in all cells and is flexible, semi-permeable barrier that surrounds the entire cell.
the cell wall provides protection and structure, while the membrane controls what enters and exits the cell.
what are some examples of prokaryotic cells
bacteria like E.coli, strep throat, cyanobacteria, algae and some archaea’s.
why are eukaryotic cells much more complex and organized
they have membrane bound organelles which allow for special complex compartmentalization and many more functions.
what are organelles
an organelle is a subcellular that preforms one or more specific functions withing a cell, similar to how our own organs function in our body.
what is a nuclear envelope
a nuclear envelope is a double membrane structure that surrounds the nucleus of a eukaryotic cell, separating the nuclear contents from the cytoplasm and acting as a barrier that regulates the movement of molecules.
what is chromatin
chromatin is a mixture of DNA and proteins that form chromosomes.
what are nuclear pores and why are they needed
the nuclear pore is a protein-lined channel in the nuclear envelope that regulates the transportation of molecules between the nucleus and the cytoplasm
what is the composition of cytoplasm
cytoplasm is primarily composed of water, salts, various organic molecules like enzymes.
what are ribosomes
a ribosome is an intercellular structure made of RNA and protein, it is the site of protein synthesis in the cell.
what do ribosomes do? are they anchored or free in the cytoplasm
ribosomes assembles amino acids into polypeptides through dehydration synthesis. then those polypeptides are folded into proteins and transported through vesicles.
they can be free in cytoplasm or anchored to the endoplasmic reticulum.
what is the endoplasmic reticulum
the ER is a network of folded sacks and tubes in the cytoplasm and can be smooth or rough.
what is the difference between smooth and rough ER
rough ER has has many ribosomes on its outer surface and makes proteins the cell needs. smooth ER makes other substances like lipids and carbohydrates and has a smooth surface.
what is the Golgi apparatus
the Golgi apparatus is an organelle that processes and packages proteins and lipids for inside and outside the sell
what are lysosomes? what do they do
lysosome is a membrane-bound organelle that contains digestive enzymes.
the lysosome functions almost as an opposite than ribosomes. one breaks down, one synthesizes.
what are mitochondria? what do they do
mitochondria are organelles that produce most of the energy that
the cells use to function.
the chemical energy produced by the mitochondria is stored in adenosine triphosphate (ATP).
what is the chemical process of cellular respiration
cellular respiration is a process by which glucose is broken down in the presence of oxygen to produce carbon dioxide, water and energy stored as ATP (adenosine triphosphate).
C6H12O6 + 6O2 → 6CO2 + 6H2O + energy (ATP)
where does the glucose come from in cellular respiration.
glucose comes from the food we eat which is broken down and rearranged into glucose during digestion. it is then absorbed into the blood stream for cells to use for energy production and storage.
what are some characteristics of chloroplasts
chloroplasts are organelles found in plant cells. It contains high amounts of the green pigment, chlorophyl. Chloroplasts are the organelle responsible for photosynthesis.
what is the chemical process of photosynthesis
the chemical process of photosynthesis is the opposite of what a mitochondria does.
It uses carbon dioxide, water, energy from sunlight to produce glucose and oxygen.
6CO2 + 6H2O + energy → C6H12O6 + 6O2
what are vacuoles? how do vacuoles in plant and animal cells differ.
vacuoles are membrane bound organelles founding plants and animals.
In plants, vacuoles can take up most of the space in the cell, and water may be a waste material, so in planta it regulates water.
In animals they function closer to lysosomes because they break down, store and regulate waste.
what is the cytoskeleton
the cytoskeleton is a network of protein fibers that provide structure and maintain the shape of cells. It also enables the cell to move in response to stimuli.
what are cilia, flagella, and pseudopods
tiny hair-like structures that protrude from the surface of cells. they the cell move, sense the environment.
a hair-like structure which functions as a whip that allows a cell to move.
pseudopods are closer to false feet. they also provide movement, and the capture of prey.
what are membranes
thin layers of either lipids and proteins, or tissues that help protect inner contents or regulate the exchange of particles through diffusion and osmosis
which transport mechanisms are passive and active?
passive transports include simple diffusion, osmosis, and facilitated diffusion.
Active transport include sodium-potassium pump, endocytosis and exocytosis.
what is the fluid mosaic model
the fluid mosaic model is a scientific model that shows the structure and function of cell membranes. It shows a “mosaic” of each of the cell membranes features.
why are phospholipids able to form membranes
because of their composition and structure, they are have both polar and non-polar features. Because of their tails being non-polar, or hydrophobic they arrange themselves as to where their tails are apart of the inner membrane, protected from water.
what are glycolipids and glycoproteins
glycolipids are lipids with carbohydrates attached.
glycoproteins are proteins with carbohydrate sugars attached.
what do carbohydrates do in the cell membrane? where are they found
carbohydrates are found on the outside of the cell with lipids and proteins.
they aid in cell recognition by acting as a marker that allow other cells to recognize each other. this also impacts the recognition of blood types. They also provide protection.
