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.