Biology Review: Variety of Living Organisms to Gas Exchange in Humans

This set of flashcards covers key concepts in biology, including characteristics of living organisms, biological molecules, food tests, enzymes, movement of substances, photosynthesis, digestion, respiration, and gas exchange.

What are the main characteristics of fungi?

Mycelium made of hyphae, chitin cell wall, saprotrophic nutrition, store carbohydrates as glycogen.

What are protoctists?

Single-celled organisms like Amoeba and Chlorella.

What are the characteristics of bacteria?

Cell wall, cell membrane, cytoplasm, plasmid, lack nucleus.

What are viruses?

Non-living, reproduce in living cells, have a protein coat.

What is a pathogen?

A microorganism that causes disease.

What elements are in carbohydrates?

Carbon, hydrogen, oxygen.

What elements are in proteins?

Carbon, hydrogen, oxygen, nitrogen.

What elements are in lipids?

Carbon, hydrogen, oxygen.

What are the monomers of carbohydrates?

Simple sugars.

What are the monomers of proteins?

Amino acids.

What are the monomers of lipids?

Fatty acids and glycerol.

What solution is used to test for glucose?

Benedict's solution.

What solution is used to test for starch?

Iodine solution.

What solution is used to test for protein?

Biuret solution.

What is used to test for lipids (fats)?

Ethanol.

What are enzymes?

Biological catalysts that break down substances without being used up.

What happens to enzymes at high temperatures?

They denature (lose shape).

What happens to enzyme activity at low temperatures?

It slows due to reduced kinetic energy.

How does pH affect enzymes?

It can alter the active site and affect substrate binding.

How can you test the effect of pH on enzyme activity?

Use buffer solutions at different pH levels and measure reaction rates.

What is diffusion?

Movement of particles from a high to low concentration.

What is osmosis?

Movement of water through a semi-permeable membrane from high to low water potential.

What is active transport?

Movement of substances from low to high concentration using energy.

What factors affect diffusion/osmosis?

Surface area to volume ratio, temperature, concentration gradient.

What is the word equation for photosynthesis?

Carbon dioxide + water -> glucose + oxygen.

What factors affect photosynthesis?

CO2 concentration, light intensity, temperature.

How are leaves adapted for photosynthesis?

Broad surface area, chloroplasts in palisade cells, stomata for gas exchange, thin for short diffusion distance.

How can you measure photosynthesis rate?

Observe oxygen production under different light, CO2, and chlorophyll conditions.

What is the function of bile?

Neutralises stomach acid and emulsifies lipids for easier digestion.

How is the small intestine adapted for absorption?

Has villi with a large surface area and rich blood supply.

What is the purpose of respiration?

Releases energy from glucose and converts it to ATP.

What is the word equation for aerobic respiration?

Glucose + oxygen -> carbon dioxide + water.

What is the word equation for anaerobic respiration in humans?

Glucose -> lactic acid.

How are alveoli adapted for gas exchange?

Large surface area, thin walls, rich blood supply.

How does smoking affect the lungs?

Damages lung tissue, reduces gas exchange efficiency, and increases lung cancer risk.

How do you measure breathing rate before and after exercise?

Use limewater to test CO2 output.

Temperature effects photosynthesis

C - temperature using water baths 5,10,15,20,26

O - pondweed if the same species

R - repeat experiment 3 times at each temperature and calculate mean

M - calculate volume of oxygen produced using gas syringe

M - over a period of 2 mins using a stopwatch

S - length of pondweed

S - light intensity