Maintaining internal environments (B3.3) | OCR GCSE Biology A (Gateway Science) — Higher (J247) | KnowledgeSet

Maintaining internal environments

Biology (Separate Science) · GCSE · OCR · OCR GCSE Biology A (Gateway Science) — Higher (J247) · Specification point · B3.3 · Organism level systems

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Learning Objectives

B3.3 Maintaining internal environments

Summary Homeostasis is crucial to the regulation of internal environments and enables organisms to adapt to change, both internally and externally. Internal temperature, blood sugar levels and osmotic balance are regulated by a number of organs and systems working together. Underlying knowledge and understanding Learners will build on the knowledge and understanding gained in section 3.1 about coordination and control when considering the topics in this section. Common misconceptions Learners often confuse type 1 and type 2 diabetes, and the effective treatments for each. The effect of ADH on the permeability of the kidney tubules is often confused.

Reference	Mathematical learning outcomes	Mathematical skills
$BM3.3i$	$extract and interpret data from graphs, charts and tables$	$M2c$

Learning outcomes	To include	Maths

$B3.3a explain the importance of maintaining a constant internal environment in response to internal and external change$	$allowing metabolic reactions to proceed at appropriate rates$		$WS1.4a$	$Research into hypothermia.$
$B3.3b describe the function of the skin in ☑ the control of body temperature$	$detection of external temperature, sweating, shivering, change to blood flow in terms of vasoconstriction and vasodilation$		$WS2a, WS2b, WS2c, WS2d$	$Demonstration of the cooling effect of sweating using alcohol based surgical wipes. (PAG B6) Investigation into heat loss by using microwaved plasticine shapes/model ‘animals’ by using a UV heat camera/thermometers. (PAG B6)$
$B3.3c explain how insulin controls blood sugar levels in the body$		$M2g$
$B3.3d explain how glucagon interacts with insulin to control blood sugar levels in the body$		$M2c$	$WS2a, WS2b, WS2c, WS2d$	$Investigations into the glucose content of artificial urine to diagnose diabetes, using e.g. Clinistix. (PAG B6)$
$B3.3e compare type 1 and type 2 diabetes and explain how they can be treated$
$B3.3f explain the effect on cells of osmotic ☑ changes in body fluids$	$higher, lower or equal water potentials leading to lysis or shrinking (no mathematical use of water potentials required)$		$WS2a, WS2b, WS2c, WS2d$	$Demonstration of the different water potentials on different cells. (PAG B6, PAG B8)$
$B3.3g describe the function of the kidneys ☑ in maintaining the water balance of the body$	$varying the amount and concentration of urine and hence water excreted$		$WS1.3b, WS2a, WS2b, WS2c, WS2d$	$Investigation of the structure of the structure of a kidney by dissection and the application of H O to visualise the 2 2 nephrons. (PAG B6, PAG B8) Investigations into the glucose content of artificial urine to diagnose diabetes, using e.g. Clinistix. (PAG B6)$
$B3.3h describe the gross structure of the ☑ kidney and the structure of the kidney tubule$	$Bowman’s capsule, proximal convoluted tubule, loop of Henlé and collecting duct$
$B3.3i describe the effect of ADH on the ☑ permeability of the kidney tubules$	$amount of water reabsorbed and negative feedback$		$WS2a, WS2b, WS2c, WS2d$	$Investigation of the different sections of a nephron and the composition of the filtrate from each area. (PAG B2, PAG B6, PAG B8)$
$B3.3j explain the response of the body to ☑ different temperature and osmotic challenges$	$challenges to include high sweating and dehydration, excess water intake, high salt intake responses to include mechanism of kidney function, thirst$			$Research into sports drinks and evaluation into which is best for athletes. (PAG B2, PAG B6, PAG B8)$