Structure of eukaryotic cells

Question 1

Nucleus

Answer 1

• controls cells activity
• makes ribosomal RNA and ribosomes
  NUCLEAR ENVOLOPE - controls entry and exit of materials and contains reactions taking place inside
  NUCLEAR PORES - allow messenger RNA out nucleus, 3000 pores in nucleus each 40-100 nm diameter
  NUCLEOPLASM - makes up bulk of nucleus
  CHROMOSOMES - protein bound linear DNA

Question 2

Mitochondrion

Answer 2

• production of ATP from glucose
  DOUBLE MEMBRANE - control entry and exit of materials. inner two membranes fold to form cristae
  CRISTAE - provide large SA for attachment of enzymes involved in respiration
  MATRIX - Contains protein, lipids, ribosomes and DNA that allows mitochondrion to make proteins

Question 3

Chloroplasts

Answer 3

• carry out photosynthesis
  ENVOLOPE - selective on what it allows in and out of the chloroplast
  GRANA - stacks of 100 disk structures called thylakoids. in the thylakoids are chlorophyll and is where first stage of photosynthesis takes place
  STROMA - Second stage of photosynthesis, starch grains present. Fluid provides all enzymes needed

Question 4

Rough endoplasmic reticulum

Answer 4

• ribosomes present on outer surface of the membrane
• provides large SA for synthesis of proteins and glycoproteins
• provide pathway for transport of materials

Question 5

Smooth endoplasmic reticulum

Answer 5

• more tubular in appearance
• synthesise, store and transport lipids
• synthesise, store and transport carbohydrates

Question 6

golgi apparatus

Answer 6

• adds carbs to proteins to form glycoproteins
• produce secretory enzymes such as in the pancreas
• transport, modify and store lipids
• form lysosomes

Question 7

Lysosomes

Answer 7

• hydrolyse material ingested by phagocytic cells
• release enzymes to the outside of the cell in order to destroy material around the cell
• completely break down cells after they have died (autolysis)

Question 8

Ribosomes

Answer 8

80s - eukaryotic cells, 25nm diameter

70s - prokaryotic cells, mitochondria and chloroplasts, slightly smaller

Question 9

cell wall

Answer 9

• made of polysaccharides

- provide mechanical strength to prevent cell bursting

Question 10

vaculoes

Answer 10

• make cells turgid
• sugars and amino acids act as energy store
• pigments may color petals to attract insects

Question 11

Tissues

Answer 11

collection of similar cells that can perform a specific function

Question 12

Tissue Example

Answer 12

EPITHELIAL CELLS - line surfaces of organs and have a protective function

Question 13

organs

Answer 13

combination of tissues that are coordinated to perform a variety of functions but have one major function