NSSCO Home Economics 6155 cheat sheet

Energy values: protein 4 kcal/g (17 kJ), carbohydrate 4 kcal/g (17 kJ), fat 9 kcal/g (37 kJ), alcohol 7 kcal/g (29 kJ); fat is the most concentrated source of food energy.

Eight amino acids are essential for adults (histidine is added for infants); the limiting amino acid is the one in shortest supply and it controls how much protein the body can build.

Vitamins A, D, E and K are fat-soluble: absorbed with dietary fat, stored in liver and adipose tissue, slow to run out but toxic in excess; B-complex and C are water-soluble, excess is excreted and cooking losses are high.

Vitamin C is destroyed by heat, air, light and alkali, and it improves absorption of non-haem iron, so serve citrus, tomato or paw-paw with beans and dark leafy vegetables.

Deficiency map: vitamin A - night blindness and infections; thiamin (B1) - beriberi; niacin - pellagra; vitamin C - scurvy; vitamin D - rickets; iron - anaemia; iodine - goitre.

Bacterial growth rule: danger zone 5-60 degrees C with fastest growth near 37 degrees C; refrigerator 0-5 degrees C, freezer -18 degrees C or colder, reheating to at least 74 degrees C, and no more than two hours for perishable food at room temperature.

Preservation principles: remove moisture (drying, salting, sugaring), lower temperature (chilling, freezing), raise acidity (pickling, fermentation), exclude air (bottling, vacuum), heat-sterilise (canning).

High-risk foods that support rapid bacterial growth are meat, poultry, fish, eggs, dairy, cooked rice and gravies; low-risk foods are dry cereals, sugar, dry bread and acid foods.

Meal-planning decision rule: first match energy and nutrient needs to age, sex, activity and health, then check cost, season, storage life, culture and religion, colour, texture, flavour, equipment and time available.

Fibre classification: natural fibres are vegetable (cotton, linen), animal (wool, silk) or mineral; manufactured fibres are regenerated from cellulose (viscose, rayon) or synthetic from petrochemicals (polyester, nylon, acrylic).

Cotton is cellulose: very absorbent, stronger wet than dry, washes hot, tolerates bleach, creases badly, and burns quickly with a steady flame and grey ash.

Wool is the protein keratin with surface scales: weak when wet, felts and shrinks under heat plus moisture plus friction, damaged by alkali and bleach, flame resistant, and burns with the smell of burning hair.

Polyester and nylon are thermoplastic: low moisture regain, fast drying, strong, and they melt into a hard bead when burned, so iron at low heat and avoid a hot tumble dryer.

Weave affects performance: plain weave is firm and stable; twill is diagonal and durable (denim); satin has long floats giving lustre but snags easily.

Pattern symbols and rules: grainline arrow parallel to the selvedge, notches matched, darts folded and stitched to shape, cutting line outside stitching line, seam allowance usually 1.5 cm (5/8 inch).

Seam choice: plain or closed seam for most woven fabrics; French seam for sheer and lightweight fabrics; overlocked or zigzag for fraying fabrics; flat fell for jeans and shirts needing strength.

Care decision rule: sort by colour, fibre and soil level; whites and lights hottest, coloureds cooler, wool and silk by hand in cool water with mild detergent; test colourfastness on a hidden seam before washing.

Repair rules: darn holes in knitwear with matching yarn, patch tears in flat fabric, sew buttons on with a thread shank, and reinforce worn edges before they break through.

Management process: planning (goals and resources), organising (who does what, when), implementing, then evaluating the result against the plan and re-planning.

Resources divide into human (time, energy, knowledge, skills, attitudes) and non-human or material (money, equipment, space, community services); unused time and energy cannot be stored, so they are lost permanently.

Work simplification uses four actions - eliminate, combine, rearrange, simplify - aiming for fewer and shorter motions, both hands working together, and a fixed storage place for each tool.

Kitchen work triangle: the paths linking sink, cooker and refrigerator; the three legs together should total about 4 to 8 metres and no leg should cross a main traffic route.

Ergonomic heights: a standing work surface is set about 5 to 10 cm below elbow height, the tallest user determines the height, and shorter users stand on a platform.

Housing functions are shelter and protection, security, privacy, and space for sleeping, eating, hygiene, study and storage; selection criteria include cost, distance to work and school, ventilation, daylight, water, sanitation, tenure and safety.

Indoor comfort zone is roughly 20-25 degrees C and 30-60 per cent relative humidity; natural ventilation removes heat, moisture, odours and carbon dioxide at no cost, while mechanical ventilation uses energy.

Family life cycle stages - beginning, expanding, launching, contracting - change the demand for space, money and time, so housing and budgets must be reviewed at each stage.

Conflict resolution rule: address the behaviour not the person, use I-statements, listen without interrupting, search for a win-win option, and review the decision later.

Growth is a measurable increase in size (mass, height, head circumference); development is an increase in the ability to perform functions such as motor, language and social skills.

Approximate milestones: social smile 6 weeks, head control 3-4 months, sits unsupported 6-8 months, pincer grasp 9-12 months, walks 12-15 months, two-word phrases 18-24 months.

Feeding rule: exclusive breastfeeding for the first six months with no water, complementary foods from six months, breastfeeding continued to two years; colostrum is the first protection against infection.

Weaning rule: one new food at a time, three to five days apart, thin texture increasing with age, no added salt or sugar, and no honey before twelve months because of the botulism risk.

Immunisation schedule in Namibia: BCG and oral polio at birth; pentavalent (DPT-HepB-Hib), oral polio and pneumococcal at 6, 10 and 14 weeks; measles at 9 and 18 months; vitamin A from six months.

Diarrhoea management: oral rehydration solution after every loose stool, continue breastfeeding and feeding, give zinc where provided, and seek care for blood in stool, sunken eyes, no urine or persistent vomiting.

Handwashing rule: soap and running water for at least 20 seconds covering palms, backs, between fingers, thumbs and nails; critical times are before preparing or eating food and after the toilet or nappy change.

Adult resting vital signs: pulse 60-100 beats per minute, respirations 12-20 per minute, oral temperature 36.5-37.5 degrees C; infants and young children normally have faster pulse and breathing rates.

Child safety rules: lock medicines and poisons out of reach, turn pot handles inward, fence pools and water containers, use a car seat, and supervise under-fives near water, roads, stairs and fires.

Budget formula: income minus (fixed expenses plus variable expenses) equals surplus or deficit; a deficit must be closed by cutting variable spending, using savings, or borrowing, which adds interest cost.

Fixed costs are contractual and unchanged month to month (rent, insurance, loan instalments); variable costs change with use (food, electricity, transport, clothing) and are the flexible part of a budget.

The 50/30/20 guide allocates about 50 per cent of net income to needs, 30 per cent to wants and 20 per cent to savings and debt repayment; it is a starting point, not a rule.

Unit pricing: divide price by quantity to get cost per kilogram, litre or 100 g; the larger pack is cheaper only when its unit price is lower and the contents will be used before spoiling.

Interest formulas: simple interest = P x r x t; compound interest A = P(1 + r/n)^(nt); the earlier money is saved, the greater the effect of compounding.

United Nations consumer rights: satisfaction of basic needs, safety, information, choice, representation, redress, consumer education and a healthy environment.

Consumer responsibilities: critical awareness, assertiveness, social and environmental responsibility, and solidarity with other consumers; keeping receipts and warranties is what makes redress possible.

Redress route: complain promptly with the receipt and evidence to the seller, then the manufacturer or importer, then the ombudsman or the national consumer and competition authority.

Waste hierarchy: refuse, reduce, reuse, repair, recycle, recover energy, then dispose; buying durable and repairable goods and avoiding single-use items cuts waste at the source.