Cells Flashcards
What is the structure and function of the nucleus?
Nuclear envelope (double membrane)
Nuclear pores (gaps in the membrane) - allows substances to move between cytoplasm and nucleus
Chromatin - made from DNA and proteins, controls cells activities
Nucleolus - makes ribosomes
What is the function of the plasma membrane?
Regulates the movement of substances in and out of the cell.
Also has receptor molecules which allows it to respond to chemicals like hormones
What is the structure of rough endoplasmic reticulum?
A system of membranes enclosing a fluid - filled space. Covered in ribosomes
What is the function of rough endoplasmic reticulum?
Folds and processes proteins that have been made at the ribosomes
What is the structure of the Golgi apparatus?
Fluid filled flattened sacs
What is the function of the Golgi apparatus?
Processes and packages new lipids and proteins which are transported around the cell by vesicles ( pm embrace bound sacs)
Also makes lysosomes
What is the structure of endoplasmic reticulum?
A system of membranes enclosing a fluid - filled space.
What is the function of smooth endoplasmic reticulum?
Synthesises and processes lipids
What is the structure of lysosomes?
Round organelle surrounded by a membrane with no clear internal structure
What is the function of the lysosomes?
Contains digestive enzymes, kept separate from the cytoplasm via it’s membrane. Used to digest invading cells or worn out organelles
What is the structure of mitochondrion?
Double membrane that folds to form structures called crista
Inside this is the matrix containing the enzymes involved in respiration
What is the function of mitochondrion?
The site of aerobic respiration, producing ATP. - a common energy source in the cell.
There are lots of mitochondria in active cells, as they require more energy
What is the structure of ribosomes?
Small organelle that is attached to endoplasmic reticulum or free in cytoplasm. It has a small and large subunit
What is the function of the ribosomes?
The site of protein synthesis
How are are small intestines adapted to absorb food in terms of cells?
The lumen surface is covered by villi made of epithelial cells, giving a larger surface area to absorb food.
How are epithelial cells adapted?
Have microvilli to provide an even larger surface area for absorption
Lots of mitochondria to provide lots of energy (ATP) for active transport of digested food molecules into the cell
What are microvilli?
Folds in the plasma membrane of cells. Found in epithelial cells
How are red blood cells adapted?
No nucleus, more room for oxygen carrying molecule haemoglobin
How are sperm cells adapted?
A lot of mitochondria to provide energy to travel distance to egg
Long tail to propel sperm there
What is the differences between eukaryotic and prokaryotic cells?
Prokaryotic cells have: Flagellum Cell wall Capsule Plasmids DNA suspended in cytoplasm ( no membrane bound organelles)
What is the function of flagellum in prokaryotic cells?
Propel cell forward?
What is the function of the cell wall in prokaryotic cells?
Keep cell rigid
What is the function of the capsule in prokaryotic cells?
Made of secreted slime which acts as protection against white blood cells
What is a prokaryotic organism?
An organism made out of just one cell
