Cell structure

Question 1

eukaryotic cells

Answer 1

-larger than prokaryotic cells
-DNA contained in a nucleus
- most eukaryotic cells are part of complex multicellular organisms containing a range of specialised cells to perform a variety of functions
-specialized cells with similar structures and functions are organised into tissues
-animals, plants and fungi are all eukaryotic organisms.

Question 2

organisms inside a eukaryotic cell

Answer 2

-cell surface membrane
-nucleus
-mitochondria
-chloroplasts
-golgi apparatus and golgi vesicles
-lysosomes
-ribosomes
-RER (rough endoplasmic reticulum)
-SER ( smooth endoplasmic reticulum)
-cell wall
-cell vacuole

Question 3

cell surface membrane

Answer 3

-found in all cells
-phospholipid bilyaer- molecules embedded within and attached on the outside (proteins carbohydrates, cholesterol)

Question 4

function - cell surface membrane

Answer 4

controls the entrance and exit of molecules

Question 5

nucleus

Answer 5

-nuclear envelope- double membrane
-nuclear pores
-nucleoplasm- granular jelly-like material
-chromosomes- protein bound linear DNA
-nucleolus- smaller sphere in the nucleoplasm which is the site of rRNA production and ribosome synthesis

Question 6

function of the nucleus

Answer 6

-site of DNA replication and transcription (making mRNA)
-contains the genetic code for each cell.

Question 7

mitochondria

Answer 7

-double membrane
-an inner membrane called the cristae
-the fluid centre called the mitochondrial matrix
-contains 70s ribosomes and circular DNA

Question 8

mitochondria function

Answer 8

site of aerobic respiration and ATP production

Question 9

chloroplasts

Answer 9

-surrounded by a double membrane
-contains thylakoids (folded membranes embedded with pigment)
-the fluid filled stroma contains enzymes for photosynthesis
-found in plants
-contains 70s ribosomes
-contains 70s ribosomes and circular DNA

Question 10

chloroplast function

Answer 10

site of photosynthesis

Question 11

golgi apparatus and vesicles

Answer 11

folded membranes making cristernae
-secretory vesicles pinch off from the cisternae

Question 12

function of golgi apparatus and vesicles

Answer 12

-add carbohydrates to proteins to form glycoproteins
-produce secretory enzymes
-secrete carbohydrates
-transport store and modify lipids from lysosomes
molecules are labelled to reach their destination
-finished products are transported to the cell surface in golgi vesicles where they fuse with the membrane and the contents are released via exocytosis.

Question 13

lysosomes

Answer 13

Bags of digestive enzymes- can contain 50 different enzymes

Question 14

function of lysosomes

Answer 14

-hydrolyse pathogens in phagocytosis
-completely break down dead cells (autolysis)
-exocytosis-release enzymes outside of the cell to destroy material
-digest worn-out organelles for reuse of materials

Question 15

ribosome

Answer 15

-small granuels made up of two subunits of protein and rRNA
-80s large ribosomes found in eukaryotic cells
-70s smaller ribosomes found in prokaryotic cells

Question 16

function of ribosome

Answer 16

the site of protein synthesis