Animal Transport A Level Full Topic Notes with Specification Points - OCR A Level Biology
120 views 0 purchase
Course
Animal Transport (H420)
Institution
OCR
Full revision notes with the corresponding points from the OCR specification. All that you need to know for the exam - whether end of topic test or the actual A Level. The topic covered is Animal Transport and explains everything with graphs and diagrams inserted into the document.
Easy to unders...
The need for transport systems in multicellular animals - an appreciation of size, metabolic rate
and surface area to volume ratio (SA:V).
Need due to:
Low SA:V (Large size)
High metabolic rate
Blood carries hormones/enzymes, food molecules and removes waste products
The different types of circulatory systems - single, double, open and closed circulatory systems in
insects, fish and mammals.
Open – Heart but few blood vessels
Closed – Blood flows through blood vessels – no contact with body cells
Single – 2 chambered heart – blood travels once through the heart for every circuit around the body
(more energy efficient as less muscles are being used) – LOW systemic pressure
Double – 4 chambered heart – blood travels twice through heart for every circuit around the body –
HIGH systemic pressure
Fish – single circulatory system
Mammals – double closed circulatory system
Insects – open circulatory system
Spiracles – trachea – tracheoles – body cells
No concentration gradient = slow and inefficient and cant change the flow of the haemolymph
(insect blood)
Haemolymph pumped heart – body cavity (haemocoel) Exchange of food and nitrogenous wastes
(NO GAS) directly at cell
The structure and functions of arteries, arterioles, capillaries, venules and veins - distribution of
different tissues within the vessel walls.
Artery – Away from heart with high oxygenation. High pressure. Pulse present. Thick muscle and
elastic layers. Narrow lumen.
Deoxygenated blood = pulmonary artery
Oxygenated blood = pulmonary vein
Artery that has valves = aorta, pulmonary artery
Vein – Into heart with low oxygenation. Low pressure. Thin muscle and elastic layers. Wide lumen
and valves present. Blood flow assisted via muscles in valves and breathing/muscular movements.
Tunica externa (Connective tissue)
Tunica Media (smooth muscle and elastic fibres) Different layers of blood vessels (starting
from the outside)
Tunica Intima (endothelium)
, Capillary – Exchanges materials e.g. oxygen and carbon dioxide. Thin tunica media. Lumen is 1 cell
thick = RBC travel in single file to increase diffusion time.
The formation of tissue fluid from plasma - reference to hydrostatic pressure, oncotic pressure and
an explanation of the differences in the composition of blood, tissue fluid and lymph
Plasma- Liquid in blood. Transport medium for CO2, hormones and urea. 55% of blood (contains
proteins and water etc)
Erythrocytes (RBC) – Delivers oxygen to tissues – picks o2 up from lungs – transports co2. Flattened
biconcave shape – no nucleus to have more space for oxygen.
Platelets – healing and repair of the tissues
Leucocytes (phagocytes) – WBC that destroys pathogens. Receptors on cell surface bind to antigens
on pathogen. Produced in bone marrow.
Leucocytes (lymphocytes) – produces antibodies. They attach to antigens. Labels pathogens so they
can get destroyed by phagocytes – stick together
Function of tissue fluid – bring o2 and nutrients to cell – remove waste products, releases metabolic
waste and exchanges substances
Hydrostatic pressure – Pressure of blood from heart contractions. Forces blood out of the capillaries.
Dissolved gases/nutrients move with it. (Arteries/arterioles and early capillaries) – TO CALCULATE =
subtract the pressure out by the pressure in.
Oncotic pressure – Tendency of water to move into blood via osmosis as a result of plasma proteins.
Water moves into capillaries to dilute the salty blood due to higher concentration. TO CALCULATE =
subtract the pressure out by the pressure in.
High hydrostatic pressure at arterial end of capillary due to contraction of the ventricles and the
narrowing of the vessels.
Ultrafiltration – useful substances e.g. glucose, water and o2) leave the blood to become tissue fluid.
Capillary – oncotic pressure -3.3kPa (no net movement)
Vein – hydrostatic pressure 2.3kPa – reabsorption into the blood vessels
Lymphatic fluid movement – there is no pump so it is only moved via contraction of skeletal muscles
Lymph functions – Removal of tissue fluid and the defence against pathogens.
Blood
Tissue Fluid
Lymph
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 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 these notes from?
Stuvia is a marketplace, so you are not buying this document from us, but from seller jazalevelnotes. Stuvia facilitates payment to the seller.
Will I be stuck with a subscription?
No, you only buy these notes for $9.08. You're not tied to anything after your purchase.