3.4- Eukaryotic Cell Structure Flashcards
Nuclear envelope
Double membrane surrounding nucleus- controls entry and exit of materials in and out of nucleus
Nuclear pores
Allows passage of large molecules eg messenger RNA out of nucleus around 3000 pores in each nucleus
Nucleoplasm
Jelly like material making up bulk of nucleus
Chromosomes
Consist of protein bound linear DNA
Nucleolus
Small spherical region within nucleoplasm- manufactures ribosomal RNA and assembles the ribosomes
Does the mitochondria have a double membrane?
Yes
Cristae
Extensions of the inner membrane of mitochondria- provide large surface area for attachment of enzymes and other proteins involved in respiration
Matrix
Makes up reminder of mitochondrion- contains protein, lipids, ribosomes and DNA- allows mitochondria to control production of their own proteins- involved respiration
Chloroplast envelope
Double plasma membrane surrounds organelle- highly selective in what it allows to enter and leave
Grana
Stacks disc structures called thylakoids
Stroma
Fluid filled matrix where second stage photosynthesis takes place
How are chloroplasts adapted to their function of harvesting sunlight and carrying out photosynthesis?
Granal membranes provide large surface area
Fluid of stroma possesses all enzymes needed to make sugars in 2nd stage photosynthesis
Chloroplasts contain both DNA and ribosomes so they can quickly manufacture proteins
Endoplasmic reticulum
system of sheet like membranes, spreading through cytoplasm
Rough Endoplasmic Reticulum
ribosomes present on outer surfaces of membranes
functions of Rough Endoplasmic Reticulum
a) provide large surface area for synthesis of proteins and glycoproteins
b) provide pathway for transport of materials, especially proteins
Smooth Endoplasmic Reticulum
lacks ribosomes on it’s surface, more tubular in appearance
functions of Smooth Endoplasmic Reticulum
a) synthesise, store and transport lipids
b) synthesise store and transport carbohydrates
Golgi apparatus
series of fluid filled, flattened and curved sacs with vesicles surrounding the edges
What does the Golgi apparatus produce?
lysosomes
What is the job of the Golgi apparatus?
processes and packages proteins and lipids
when are lysosomes formed ?
when vesicles produced by Golgi apparatus contain enzymes such as proteases and lipases
Function of lysosomes
remove useless and dangerous material e.g bacteria and reuse the useful parts, disposing of only that which cannot be recycled
centrioles
hollow cylinders, involved in producing spindle fibres for cell division
ribosomes
site of protein synthesis, composed of 2 sub units
what ribosomes are found in eukaryotic cells?
80S
what ribosomes are found in Prokaryotic cells?
70S
lysosomes
vesicles containing digestive enzymes bound by a single membrane
What is the cell wall made of ?
peptidoglycan
capsule
protective slimy layer which helps cell to retain moisture and adhere to surfaces
pili
hair like structures which attach to other bacterial cells
mesosomes
Infoldings of the inner membrane which contain enzymes required for respiration
function of vacuole
support plants, make turgid
sugars and amino acids make temporary food store
pigments may color petals to attract pollinating insects
what is the name of the single membrane surrounding the vacuole?
tonoplast
