'This Grade 8 Natural Sciences Noteset contains comprehensive summaries of all topics covered in the syllabus during Term 1 to 4. It is a must-have for any student looking to excel in their Grade 8 Natural Sciences exam. These notes are perfect for revision, helping students to quickly and accurate...
, Photosynthesis & Respiration
ENERGY > SUSTAINING LIFE:
→ energy need (to sustain life) = drives the interactions in ecosystems
All living things need energy for life processes:
Z Movement
Z Growth
Z Stay warm
[Sun = source of energy in ecosystems]
Z Light
Z Heat
[Plants = capture light energy > photosynthesis]
PHOTOSYNTHESIS:
→ chemical process during which plants glucose from carbon dioxide (from the air) and
water (from the ground) by using energy from the Sun;
[BYPRODUCT / BYPRODUCT = oxygen]
[Chlorophyll →green matter in plants that absorbs/captures the energy of sunlight]
GLUCOSE:
→ sugar > simplest form of food
→ Plants turn glucose into starch, cellulose and other chemical compounds [required for
growth and reproduction]
➢ Food's energy content is measured in kilojoules (kJ) OR kilocalories (kCal)
➢ The energy stored in food can be measured by burning a small amount of food in an
instrument called a calorimeter.
[Glucose = broken down → energy is used → used for bodily processes
[RESPIRATION]]
[RESPIRATION →process by which energy is released from glucose during
a series of chemical reactions]
RESPIRATION & BREATHING:
DIFFERENT WAYS OF BREATHING:
➢ Fish → gills
➢ Whales → holes on top of head
➢ Caterpillars → holes against body
➢ People → nasal cavities (air goes to lungs)
QUIIIIZZZZ!!!
WHY DO YOU BREATHE HARDER WHEN YOU EXERCISE?
➢ Respiration takes place in every cell of your body.
➢ When you jog or do exercises you need more energy.
➢ This means that respiration takes place faster and that you therefore need more
oxygen than usual.
➢ Your body automatically responds to the need for more oxygen by breathing
harder and faster.
[ECOLOGY → branch of the sciences that studies the interaction of
organisms with other organisms and their environment]
Ecologist > Person who studies these relationships and interactions
4 LEVELS > STUDY OF ECOLOGY:
→ group of organisms of the same species that are found in a
POPULATION specific area at a specific time and they must be able to breed in
that area
[population growth & factors affecting population growth or decline]
→all the populations of organisms that interact in a specific area
COMMUNITY [2 OR MORE POPULATIONS]
→communities' interaction with the non-living things in their
ECOSYSTEM environment
[community + habitat]
→all the ecosystems on Earth combine to form the biosphere
BIOSPHERE
ECOSYSTEMS > BIOTIC & ABIOTIC COMPONENTS:
BIOTIC ABIOTIC
[LIVE] [NON-LIVING]
Z Plants Z Temperature
Z Animals Z Sunlight
Z People Z Water
Z Wind
Z Sand
SURVEY METHODS > SIZE OF ECOSYSTEM:
SQUARE SURVEYS CROSS SECTION SAMPLING
→a square or grid for surveys →a line through the study area for sampling
[PLANTS / SLOW MOVING ANIMALS] [STATES OF ABIOTIC FACTORS
CHANGE]
Les clients de Stuvia ont évalués plus de 700 000 résumés. C'est comme ça que vous savez que vous achetez les meilleurs documents.
L’achat facile et rapide
Vous pouvez payer rapidement avec iDeal, carte de crédit ou Stuvia-crédit pour les résumés. Il n'y a pas d'adhésion nécessaire.
Focus sur l’essentiel
Vos camarades écrivent eux-mêmes les notes d’étude, c’est pourquoi les documents sont toujours fiables et à jour. Cela garantit que vous arrivez rapidement au coeur du matériel.
Foire aux questions
Qu'est-ce que j'obtiens en achetant ce document ?
Vous obtenez un PDF, disponible immédiatement après votre achat. Le document acheté est accessible à tout moment, n'importe où et indéfiniment via votre profil.
Garantie de remboursement : comment ça marche ?
Notre garantie de satisfaction garantit que vous trouverez toujours un document d'étude qui vous convient. Vous remplissez un formulaire et notre équipe du service client s'occupe du reste.
Auprès de qui est-ce que j'achète ce résumé ?
Stuvia est une place de marché. Alors, vous n'achetez donc pas ce document chez nous, mais auprès du vendeur notedx19. Stuvia facilite les paiements au vendeur.
Est-ce que j'aurai un abonnement?
Non, vous n'achetez ce résumé que pour €6,74. Vous n'êtes lié à rien après votre achat.
