cells Flashcards
what is tissue
- group of cells that do a specific job - tightly bound with junctions to stop bacteria entering the body
- organisation of neurons effects the job they’re doing
what is an organ
- those tissues are organised to make an organ.
- organs do a more generalised job eg brain = infomation processing → but then diff parts of brain specialise in diff things
what is an organ system
- combination of organs, eg digestive system
OR
- brain + spinal cord + nervous system
an organism
centrel organism doesn’t work alone, combination of organ systems
the levels of organisation
- organelle
- cell
- tissue
- organ
- organ system
- organism
what do cells do ?
5
- detecting
- signalling
- digesting, absorbing or transporting
- fighting infection
- moving
detecting
what do cells do ?
sensory neurons, pancreatic beta cells
signalling
what do cells do ?
neurons, endrocrine cells
digesting, absorbing or transporting
what do cells do ?
epithelial cells, red blood cells, exocrine cells [secrete sweat, tears etc]
fighting infection
what do cells do ?
leukocytes
moving
what do cells do ?
cardiac muscle, smooth muscle or skeletal muscle cells
what do cells do [processes]
5
- make things
- break things down
- change membrane voltage
- secrete/transport things
- detect things
make things
what do cells do [processes]
- proteins
- lipids
- mRNA
- DNA
- ATP
break things down
what do cells do [processes]
- glucose
- proteins
- carbohydrates
change membrane voltage
what do cells do [processes]
especially neurons, muscle cells
secrete/transport things
what do cells do [processes]
- neurotransmitters, glucose, digestive enzymes, sweat, ions
detect things
what do cells do [processes]
- light
- sound
- levels of diff molecules **eg ATP, calcium **
what is the cell membrane
- a thin coat of phospholipids that surrounds a cell and controls what enters and leaves the cell
- inside and outide of the cell are different
- proteins in the membrane that controls what comes in and out
what is cytoplasm
- the material inside the cell membrane, including the watery cytosol and other cell structures except the nucleus if one is presnt
- contains diff organelles, and cytosol
cytosol contents
5
- Water (~ 70%)
- Ions, e.g. Na+, Ca2+
- Small molecules, e.g. ATP, glucose
- Amino acids (building blocks for proteins)
- Soluble proteins
what is the cytoskeleton
- network of filaments and tubules that crisscross the cytoplasm and help maintain the cell’s ahep
what is the nucleus
- an organelle that contains most of their cell’s DNA and acts as the control center of the cell
- controls what gense are expressed and proteins get made
what is DNA
- is a nucleic acid found in cells
- contains the genetic instructions that cells need to make proteins
what are ribsomes
- structures found in all cells that are the site of protein synthesis