Prokaryotic (and Eukaryotic) cells

Question 1

prokaryotic cells

Answer 1

-make up single-celled prokaryotic organisms
-smaller than eukaryotic cells
-cells arise from other cells by binary fission
-don’t have membrane-bound organelles

Question 2

eukaryotic cells

Answer 2

-make up complex eukaryotic organisms
-larger than prokaryotic cells
-cells arise from other cells by mitosis or meiosis
-have membrane-bound organelles

Question 3

animal cell organelles

Answer 3

-mitochondria
-ribosomes
-ER
-golgi
-lysosomes
-nucleus

Question 4

plant cell organelles

Answer 4

-vacuole
-chloroplasts
-cell wall
-all the organelles found in animal cells too

Question 5

algal cell organelles

Answer 5

-exactly the same as for plant cells

Question 6

fungal cell organelles

Answer 6

similar to plant cells, but:
-they have no chloroplasts
-cell wall is made from chitin instead
-they can be multicellular

Question 7

structure of the nuclear envelope

Answer 7

-a double-membrane structure with lots of pores
-the inner and outer membranes are both phospholipid bilayers

Question 8

function of the nuclear envelope

Answer 8

-its pores control the passage of ions, molecules and RNA between nucleoplasm and cytoplasm

Question 9

structure of the nucleus

Answer 9

-has the nucleoplasm (semi-solid fluid) where we find chromatin and the nucleolus
-contains linear chromosomes made up of DNA (only in eukaryotes)
-has a nucleolus (plural is nucleoli)

Question 10

function of the nucleus

Answer 10

-controls cell activity
-the DNA it contains, has the instructions for protein synthesis
-ribosomal RNA is joined together with associated proteins in the nucleolus to assemble the ribosomal subunits

Question 11

structure of the nucleolus

Answer 11

-the largest sub-structure in the nucleus
-made from proteins like RNA, and DNA

Question 12

function of the nucleolus

Answer 12

-the site where ribosomes are made
-has secondary roles like immobilising proteins and forming signal recognition particles

Question 13

structure of mitochondria

Answer 13

-oval-shaped, double-membrane organelles that have their own ribosomes and DNA
-each membrane is a phospholipid bilayer embedded with proteins
-inner membrane has folds called cristae
-mitochondrial matrix is the area surrounded by the cristae
-the matrix contains enzymes used for respiration

Question 14

function of mitochondria

Answer 14

-they make ATP via aerobic respiration

Question 15

what does ATP stand for?

Answer 15

adenosine triphospate

Question 16

function of chloroplasts

Answer 16

-carry out photosynthesis to make food (sugars) for the plant

Question 17

structure of chloroplasts

Answer 17

-they have their own DNA, ribosomes and are double-membrane organelles
-thylakoids are the stacked, fluid-filled membrane sacks (found in inner-membrane)
-each stack of thylakoids is called a granum (plural is grana)
-grana is linked by lamellae, which are flat, thin parts of thylakoid membrane
-the fluid enclosed by the inner membrane that surrounds the grana is called stroma

Question 18

structure of the golgi apparatus

Answer 18

a series of flattened membranous sacs

Question 19

function of the golgi apparatus

Answer 19

-transport vesicles are made from the RER and fuse with the golgi apparatus
-the transport vesicles empty proteins and lipids into the lumen of the golgi apparatus
-as the proteins and lipids travel through the golgi, they are sorted packaged and tagged so that they can be sent to the right place

Question 20

structure of golgi vesicles

Answer 20

-they are membrane-bound and fluid-filled, and found in the cytoplasm
-lysosomes are a type of golgi vesicle
-small and round

Question 21

function of golgi vesicles

Answer 21

-they store and transport modified proteins and lipids from golgi apparatus to target cells
-e.g. lysosomes - which contain enzymes called lysozyme
-lysozymes aid the breakdown of proteins, polysaccharides, lipids, nucleic acids, and old organelles

Question 22

structure of ribosomes

Answer 22

-can either be floating in cytoplasm or attached to the cytoplasmic side of ER
-small organelles made of protein sub-units which means they are not covered by a membrane

Question 23

function of ribosomes

Answer 23

-in charge of protein synthesis

Question 24

structure of the ER

Answer 24

-a series of interconnected, membranous sacs and tubules
-its membrane is a phospholipid bilayer embedded with proteins
-SER has no ribosomes
-RER does have ribosomes

Question 25

function of RER

Answer 25

-responsible for processing and folding proteins

Question 26

function of SER

Answer 26

-responsible for making and processing lipids