Structure Of Eukaryotic Cells

Question 1

Structure of nucleus ?

Answer 1

. Nuclear envelope- double membrane
. Nuclear Pores
. Nucleoplasm - granular, jelly like material
. Chromosomes- protein bound linear DNA
. Nucleolus- site of rRNA production and makes ribosomes

Question 2

Function of nucleus?

Answer 2

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

Question 3

Structure of endoplasmic reticulum?

Answer 3

. Rough and Smooth ER both have folded membranes called cisternae
. Rough have ribosomes on cisternae

Question 4

Function of ER?

Answer 4

. RER- protein synthesis site
. SER- synthesis of lipids and carbohydrates

Question 5

Structure of Golgi apparatus and vesicles?

Answer 5

. Folded membranes making cisternae
. Secretary vesicles pinch off from cisternae

Question 6

Function of Golgi apparatus and vesicles?

Answer 6

. Add carbohydrates to proteins from glycoproteins
. Produce secretory enzymes
. Secrete carbohydrates
. Transport, modify and store lipids
. Form lysosomes
.finished products transported to cell surface in Golgi Vesicles where they fuse with the membrane and the contents are released in Golgi vesicles

Question 7

Structure of lysosomes?

Answer 7

Bags of digestive enzymes

Question 8

Function of lysosomes?

Answer 8

. Hydrolyse phagocytic cells
. Completely break down dead cells- autolysis
. Exocytosis - enzymes released to outside of cell to destroy material
. Digest worn out organelles for reuse of materials

Question 9

Structure of mitochondria?

Answer 9

. Double membrane
. Inner membrane called cristae
.fluid centre called mitochondrial matrix
.loop of mitochondria DNA

Question 10

Function of mitochondria?

Answer 10

. Site of aerobic respiration
. Site of ATP production
. DNA to code for enzymes needed in respiration

Question 11

Structure of ribosomes?

Answer 11

. Small, made up of 2 subunits of protein and rRNA 80s- large ribosome found in eukaryotic cells
.70S- smaller ribosomes found in prokaryotic cells, mitochondria and chloroplast

Question 12

Function of ribosomes?

Answer 12

Site of protein synthesis

Question 13

Vacuole structure?

Answer 13

. Filled w fluid surrounded by a single membrane called a tonoplast

Question 14

Function of vacuole?

Answer 14

. Make cells turgid so provides support
. Temp store of sugars and amino acids
. Pigments may colour petals to attract pollinators

Question 15

Structure of chloroplast?

Answer 15

. Surrounded by double membrane
. Contains thylakoids ( folded membranes)
. Fluid filled stroma contains enzymes for photosynthesis

Question 16

Function of chloroplast?

Answer 16

Site of photosynthesis in plants

Question 17

Structure of cell wall?

Answer 17

. Plants- made of micro fibrils of cellulose polymer
. Fungi- made of chitin, a nitrogen containing polysaccharide

Question 18

Function of cell wall?

Answer 18

Provide structural strength to cell

Question 19

Structure of plasma membrane?

Answer 19

. Phospholipid bilayer- molecules embed within and attached on outside ( proteins, carbohydrates, cholesterol)

Question 20

Function of plasma membrane?

Answer 20

Control entrance and exit of molecules