BIOLOGY: EDEXCEL IAL UNIT 2 - PAST PAPER
QUESTIONS
Similarities between mitochondria and chloroplasts. - answers- 1) surrounded by a
double membrane.
2) circular dna
Give one difference between an organ and a tissue. - answers- ø an organ has many
functions, tissue has one.
Ø an organ has many cell types, tissue only has one.
Suggest one way in which tissues and organs are similar. - answers- both have cells
that work together to carry out a specific function.
Name the adaptation that allows sheep to learn to ignore sounds that have no
importance to them. - answers- behavioural
Name the adaptation that allows the formation of a sun tan when human skin is
exposed to sunlight. - answers- physiological
Describe and explain 2 adaptations of the human egg cell. - answers- 1) haploid/ 23
chromosomes.
2) so that diploid number can be restored at fertilisation.
5) large cell surface area.
6) increased change of fertilisation.
7) cortical granules/ lysosomes/ zona pellucida.
8) to prevent polyspermy.
Suggest why the tip of the root is used when observing mitosis. - answers- site of cell
division/ mitosis/ actively dividing cells/ meristem.
Suggest why cut root tips are placed in acid when preparing a root tip squash. -
answers- to soften the material/ macerate/ break middle lamella/ eq.
The tip of the growing pollen time releases digestive enzymes into the style.
, Suggest the role of these digestive enzymes in the growth of the pollen tube. -
answers- 1) idea of breakdown/ digestion of style.
2) breaks down protein/ pectin/ middle lamella.
3) ref. To hydrolysis.
4) easier for pollen tube to grow/ reduced resistance.
5) supplies nutrients/ energy for pollen tube growth.
Suggest why bioplastic is described as a more sustainable form of packaging than oil-
based plastics. - answers- 1) bioplastic/ starch comes from plants.
2) plants/ starch are renewable.
3) oil-based plastic is from non-renewable resource/ eq.
Suggest one environmental advantage of using biodegradable packaging. - answers-
will not accumulate/ not contribute to landfill/ can be decomposed.
Explain how newly made proteins from the rer end up as glycoproteins on the cell
surface membrane. - answers- 1) protein released from ribosome/ eq.
2) enters the rer.
3) becomes packaged into (rer) vesicles.
4) vesicles/ proteins move to golgi apparatus/ vesicles fuse with/ protein enters golgi.
5) protein modified/ carbohydrate added eq.
6) then become packaged into (secretory) vesicles/ eq.
7) vesicles move towards/ fuse with the cell surface membrane.
Totipotent stem cells - answers- 1) undifferentiated/ unspecialised stem cell.
2) that can differentiate/ give rise to all/ any cell types.
3) can keep dividing.
Suggest one risk to the person receiving stem cells? - answers- possible route to
infection/ rejection by recipient/ increased risk of becoming cancerous.
Genetic material in animal and plant cells. - answers- separate strands.
Which cells are centrioles found in? - answers- animal cells only.
Which cells have cell surface membranes? - answers- animal, plant and prokaryotic
cells.
In which cells are pits found? - answers- plant cells only.
In which cells is the tonoplast present? - answers- plant cells only.
In which cells are cell walls found in? - answers- plant and prokaryotic cells.
What are the 80s ribosomes attached to in the rer? - answers- cisterna.
The benefits of buying summaries with Stuvia:
Guaranteed quality through customer reviews
Stuvia customers have reviewed more than 700,000 summaries. This how you know that you are buying the best documents.
Quick and easy check-out
You can quickly pay through EFT, credit card or Stuvia-credit for the summaries. There is no membership needed.
Focus on what matters
Your fellow students write the study notes themselves, which is why the documents are always reliable and up-to-date. This ensures you quickly get to the core!
Frequently asked questions
What do I get when I buy this document?
You get a PDF, available immediately after your purchase. The purchased document is accessible anytime, anywhere and indefinitely through your profile.
Satisfaction guarantee: how does it work?
Our satisfaction guarantee ensures that you always find a study document that suits you well. You fill out a form, and our customer service team takes care of the rest.
Who am I buying this summary from?
Stuvia is a marketplace, so you are not buying this document from us, but from seller GEEKA. Stuvia facilitates payment to the seller.
Will I be stuck with a subscription?
No, you only buy this summary for R204,65. You're not tied to anything after your purchase.