Cell Structure EXAM QUESTIONS Flashcards
What is a nuclear envelope? [1 mark]
DOUBLE membrane w/ nuclear pores to control substances that exit/enter nucleus.
What is the function of a mitochondria? [1 mark]
The site of AEROBIC respiration and production of ATP.
Where are the cristae found within a cell and what process occurs there? [2 mark]
Folds in the INNER membrane of the mitochondria.
They are the site of PHOSPHORYLATION.
What is the rough endoplasmic reticulum? [2 marks]
System of MEMBRANES that is continuous with the nucleus…
with RIBOSOMES on the outer surface.
Folds proteins
Site of SYNTHESIS and TRANSPORATION of proteins and glycoproteins.
How does the structure of the rough endoplasmic reticulum help enable synthesis of proteins? [2 marks]
The RER has RIBOSOMES and a large SURFACE AREA.
What is the smooth endoplasmic reticulum? [2 marks]
System of MEMBRANES with no ribosomes on outer surface.
Site of LIPID SYNTHESIS, storage and transport of lipids and carbs.
What are the 4 functions of the Golgi apparatus? [4 marks]
1) Produces secretory ENZYMES and carbohydrates.
2) Stores and modifies proteins & triglycerides.
3) Forms vesicles for transporting proteins/triglycerides.
4) Forms lysosomes.
What is a lysosome? [1 mark]
A membrane-bound organelle that releases HYDROLYTIC enzymes.
Break down excess or WORN-OUT cell parts.
Destroys invading viruses and BACTERIA
.
What are grana? [1 mark]
Stacks of THYLAKOIDS found in the chloroplast.
What are thylakoids? [2 marks]
Flattened SACS in the chloroplast, containing CHLOROPHYLL.
Site of the light - dependent reaction for PHOTOSYNTHESIS.
What is the stroma? [2 marks]
The MATRIX (body) of the chloroplast in a plant cell.
Site of the light - independent reaction for photosynthesis.
What is the function of the plant cell wall? [2 marks]
Provides RIGIDITY to the cell and stops the cell from BURSTING by exerting inward pressure to prevent osmosis.
Prevents cell losing its shape.
Physical BARRIER against PATHOGENS.
What are plant cell walls mainly composed of? [1 mark]
The polymer, cellulose.
What is the matrix in the mitochondria? [1 mark]
Fluid MATRIX (gap inside mitochondria) contains enzymes involved in respiration.
What is the structure function of the vacuole in a plant cell? [3 marks]
A fluid-filled sac with a single membrane (TONOPLAST)
It supports the plant by making cells TURGID.
Absorbs & hydrolyses harmful substances to DETOXIFY cytoplasm.
Stores sugars and amino acids which can act as a temporary FOOD STORAGE.
