Cell Structure Flashcards
Cell membrane
Membranous envelope surrounding cytoplasm
- holds the contents of the cytoplasm in place and regulates transport in and out of cell (imports nutrients, excretes waste)
- consists of a phospholipid bilateral that is semi-permeable
Border guard
Cell wall
Surrounds cell membrane
Only found in plant cells
- provides shape and rigidity
- made of cellulose (carbohydrate) instead of lipids
Endoplasmic recticulum
Series of numbers, canals the emulate from the nucleus, and extend through the cytoplasm, allowing for rapid transportation of materials throughout the cell
- highway system
RER
ER that is covered in ribosomes, and appears bumpy under a microscope
- The ribosomes attached to the RER allow for the rapid production and secretion of proteins
-cells that secrete lots of proteins, such as pancreatic cells require lots of RER
SER
ER that lacks any attached ribosomes appears smooth under microscope, responsible for producing lipids,
Cells that secrete lots of lipids, such as Pituitary cells require lots of SER
Nucleolus
Store inside nucleus, responsible for building ribosomes
Nuclear membrane
The double layered outer membrane of the nucleus, responsible for forming barrier between the DNA and cytoplasm, and then the space between the two layers of nuclear membrane becomes the endoplasmic reticulum.
- The nuclear membrane is semi permeable, and contains nuclear pores that allow material to be transported in and out of the nucleus.
Ribosomes
Responsible for producing proteins I’ve found either attached to the ER (proteins exported out of cell) or suspended in cytoplasm (proteins used in cell).
They are the smallest organelles, and like a membrane
- found in both eukaryotic and prokaryotic cells
the factories.
Golgi apparatus
Responsible for packaging proteins and lipids to be secreted from the cell
- looks like a stack of pancakes under microscope
- the lipids and proteins destined to exit the cell are transported from the ER to the Golgi, the Golgi wraps these proteins and lipids in a membrane and attaches glycoproteins (molecule of protein and sugar) that allows it to pass through the cell membrane
the post office of the cell
Lysosomes
They move freely through the cytoplasm, recycling old cell parts, breaking down food particles and destroying pathogens. They use a combination of enzymes and free radicals (charged oxygen ion to rip apart unwanted proteins).
When cells are dying faster than your bodies lysosomes can recycle the dead cell parts, the buildup of cellular debris is pus
- cells contain lysosomes when they either need to break down dangerous chemicals (liver cells) or destroy pathogens (white blood cells)
Lysosomes are the garbage, collectors and police.
Plastids
Produce and stores sugar molecules
- contains pigments with chemicals, responsible for photosynthesis
- pigments use visible light energy to react carbon dioxide and water, forming sugar and oxygen
Energy + 6CO2 + 6H2O -> C6H12O6 + 6O2
Chloroplast- chlorophyll - green
Chromoplast - orange- yellow
Vacuole
Large fluid filled sac within plant cell that stores nutrients and water
-looks like bubble under microscope
Mitochondria
Responsible for providing the cell with energy, suspended in the cytoplasm, and appears as ovals with finger like projections pointing towards the centre -the finger like projections is due to the folding of the mitochondria’s inner membrane: the Cristae
- specializes in performing cellular respiration and its power plant of the cell
-food particles, once converted to glucose, are reacted with oxygen molecules at the Cristae, producing water, carbon dioxide and energy.
C16H12 + 6O2 -> 6CO2+ 6H2O + energy
-contains DNA, result of Endosymbiosis
- reproduce separately form rest of cell, inherited through mothers egg
Adenosine Triphosphate (ATP&ADP)
The energy produced by the mitochondria is trapped in the molecule, called adenosine triphosphate, which is the basic unit of energy for all living things
-when a chemical reaction requires energy to occur a molecule of ATP breaks down one of its phosphate bonds, transferring the energy from that bond, when ATP is used up it releases a phosphate and becomes adenosine diphosphate, which then returns to the Cristae to have its phosphate replenished
-although cellular respiration is the primary form of energy production for all living things, not a perfect process only a third of the energy gets converted to ATP other 2/3 lost to heat
Cytoplasm 
Suspends the organelles, stores nutrients and allows the transportation of molecules
the fluid contained in the cell outside of the nucleus
(but the fluid contained inside the nucleus is nucleoplasm)
