Nature and Variety of Living Organisms Flashcards
List the 8 characteristics of all living organisms;
- Require nutrition
- Respire
- Excrete waste
- Respond to surroundings
- Move
- Control their internal condition
- Reproduce
- Grow and develop
Describe three differences between the structure of a plant vs an animal cell
- Plants have a cell wall, animals do not
- Plants have chloroplasts, animals do not
- Plants have cytoplasm; animals have small vacuole s
What are the chemical elements present in carbohydrates?
Carbon, hydrogen and oxygen
What are the chemical elements present in proteins?
Carbon, hydrogen, oxygen and nitrogen
What are the chemical elements present in lipids?
Carbon, hydrogen, oxygen, nitrogen and phosphorus
What is the balanced word equation for photosynthesis?
Carbon dioxide + water = glucose and oxygen
What is the balanced chemical equation for photosynthesis?
6CO2 + 6H2O → C6H12O6 + 6O2
How do levels of CO2 affect the rate of photosynthesis?
Since it’s a reactant, when the levels of CO2 increases, the rate of photosynthesis will therefore increase, and vice versa
How do levels of light intensity affect the rate of photosynthesis and the appearance of the leaf?
High light intensity increases the rate, and provide strong branches and dark green pigmentation
however low light intensity slows growth, and may cause leaf size to increase in size and become much lighter
How does temperature affect the rate of photosynthesis? Fully explain
At low temperature, the rate of photosynthesis is limites by the amount of mollecular collisions between enzymes and substrates. At high temperatures, enzymes will denature.
Describe a balanced diet:
Appropriate proportions of
- Carbohydrate
- Lipid
- Protein
- Vitamins
- Minerals
- Water
- Dietary fibre ( like oats )
Expain how energy requirements vary with age and activity levels
Children and adolscents require more energy for growth and development in comparison to adults.
Also, most adults are less active as they get older, so energy requirement goes down.
How do energy requirements change with pregnancy?
Extra energy is required for the growth and maintenence of the fetus and placenta.
Describe some characteristics and structure of fungi
- Not able to carry out photosynthesis
- Bodies usually organised into a mycelium from thread-like structures called hyphae
- Feed by saprotrophic nutrition (secreting digesting enzymes onto food & absorbing organic products)
Describe some characteristics and structure of protoctists
- microscopic, single celled organisms
- Some live in pond water and have features like an animal cell (Ameoba) while others (Chlorella) have chloroplasts and are more like plants.
- A pathogenic example is Plasmodium, responsible for causing malaria
