(3.2.1.1) eukaryotic cells Flashcards
what is the structure and function of a cell-surface membrane?
cell-surface membranes control exchange between the cell and it’s environment.
- selectively permeable with a phospholipid bilayer with many transport proteins embedded in it and receptors for cell recognition.
what is the structure and function of the nucleus?
the site of DNA replication and transcription; contains the genetic code used to make proteins
- nucleoplasm contains chromatin, which condenses to from chromosomes with histones
- nuclear envelope double membrane which contains pores to allow mRNA to leave and nucleotides to enter
- nucleolus for ribosome and rRNA synthesis.
what is the structure and function of mitochondria?
the site of aerobic respiration, using oxygen to make ATP
- double membrane with inner membrane folded to create cristae that has large surface area for ATP synthesis
- matrix contains enzymes, circular DNA and 70S ribosomes used to make proteins
what is the structure and function of the chloroplast?
plant and algal cells only!
chlorophyll absorbs light for photosynthesis to produce organic molecules
- double membrane with inner membrane folded into thylakoids that stack into grana.
- stroma contains circular DNA and 70s ribosomes used to make proteins
- can contain starch grains
what is the structure and function of the ribosomes?
site of translation in protein synthesis
- made up of only rRNA and protein (no membranes)
what is the structure and function of the rough endoplasmic reticulum?
- site of protein synthesis and folds polypeptides to secondary and tertiary structures
- packaging into vesicles to transport to golgi
covered in ribosomes
what is the structure and function of the smooth endoplasmic reticulum?
site of lipid and steroid synthesis via cisternae found throughout the cell
no ribosomes!
what is the structure and function of the golgi apparatus?
modifies proteins received from rER to form glycoproteins and packages proteins into vesicles to transport to cell membrane for exocytosis
- can also form lysosomes if vesicles contain hydrolytic enzymes
what is the function of lysosomes?
contains digestive enzymes to hydrolyse pathogens, bacteria or cell waste products
what is the function of the cell wall?
plant, bacterial and algae cells only!
provides structual strength, rigidity and support to help cell resist osmotic pressures
- made of microfibrils of cellulose (in plants), made of chitin (in algae) and made of murein (in prokaryotes)
