week 1 Flashcards
what is the level of organisation
atom
cell
tissue
organ
organ system
organism
what is a cell
the simplest unit of life making up the structure and function
draw a phosolipid bilayer
hydrophilic head
hydrophobic tail
protein channel
protein pump
aquaporisis
Describe the major age-related changes in cells
Some body cell types never divide or have a limited capacity to undertake mitosis . Therefore, damaged cells may not be replaced which reduces the function of the tissues and organs.
slowing down vital cell processes.
Telomeres, the protective DNA “cap” on chromosome ends, typically get shorter each cell division, which can result in the erosion of chromosomes and loss of functional chromosome material.
Glucose is randomly added to proteins, -> increased stiffness and loss of elasticity in tissues.
Changes in cell identifying markers at the surface of the cells can cause antibodies to attach to and mark the cell for destruction (increases autoimmunity)
simple diffusion
the movement of a molecule directly through the phospholipid bilayer
small, uncharged, lipid-soluble materials
facilitated diffusion
the movement of an ion or molecule from an area of higher concentration to an area of lower concentration (until the concentration is the same on both sides of the membrane), via a channel or carrier protein.
hydrophilic, or charged, or larger materials
osmosis
the movement of water molecules to an area of higher solute concentration, where the concentration of water is lower.
primary active transport
the movement of an ion or molecule from an area of lower concentration to an area of high concentration, via a channel or carrier protein.
and uses ATP
secondary active transport
the movement of an ion or molecule from an area of lower concentration to an area of high concentration, via a channel or carrier protein.
using another substance which is then returned the area of high concentration using atp
exostosis
the release of fluids and/or solids from the cell via intracellular vesicles. ATP is required.
endocytosis
the packaging of extracellular materials into a vesicle for transport into the cell. ATP is required.
what is the difference between the nervous system and the endocrine system in msinitaing homeostasis
nervous system- sends signal to brain
endocrine- produces hormone
what is the difference between indirect and direct cell to cell communications
direct= cells need to have contact to send signalling
indirect= no direct connection needs
endocrine
cell produces hormone which goes into the blood to reach the target cell
paracrine
the cell produces the hormone which goes to the target cell
