chapter 1 - cells Flashcards
what are cytologists?
scientists who study the structure and function of cells
what are cells
the basic unit of the human body
what are the parts of the cells
membrane - controls what goes in and out of the cell
nucleus - controls the activities of the cells and contains the genetic make up
cytoplasm - where most of the chemical reactions take place
mitochondria - releases energy in respiration
ribosomes - produce proteins for example insulin
what is a tissue
a group of cells with similar structure and function
what is a organ
a group of tissues carrying out a particular function
the skin is the largest organ
what are organ systems
group of organs that perform a particular function
what good things come into cells
molecules and ions move from the outside into cells and between cells
nurtients reached the cells by the digestive system and oxygen by the lungs
what is diffusion
the movement of molecules from a high concentration to a low concentration
what is osmosis
the diffusion of water from a high concentration to a low concentration over a partially permeable membrane
what are enzymes
enzymes are catalysts and are important in both building up and breaking down processes
what effects and enzyme
temperature and ph
- they can be denatured
what is respiration
respiration is the release of energy within a cell from food molecules
all living cells respire, food is the main energy supply
what is energy needed for
growth
building large molecules from smaller ones
keeping warm
what does aerobic respiration do
uses oxygen and produced carbon dioxide releasing a large amount of energy
when does anaerobic respiration occur
during vigourous physical exercise
