Biology Exam Revision Flashcards

A collection of flashcards derived from biology lecture notes for exam preparation.

What are the three main principles of the Cell Theory?

1. All organisms are composed of one or more cells. 2. The cell is the basic unit of structure and organization in organisms. 3. All cells come from preexisting cells.

What are the seven characteristics of life?

1. Movement. 2. Respiration. 3. Sensitivity. 4. Growth. 5. Reproduction. 6. Excretion. 7. Nutrition.

Why are viruses considered non-living entities?

Viruses lack cellular structure, independent metabolism, and can only reproduce with a host, but they have genetic material and can evolve.

What is the function of the coarse focus knob on a microscope?

It is used to bring the specimen into approximate or near focus.

What does the Golgi Apparatus do in a cell?

Processes, modifies, packages, and distributes macromolecules like proteins and lipids.

What is osmosis?

The movement of water from a hypotonic solution to a hypertonic solution through a semipermeable membrane.

Explain the difference between active transport and passive transport.

Active transport requires energy to move substances against the concentration gradient, while passive transport does not require energy and moves substances down their concentration gradient.

What are embryonic stem cells?

Undifferentiated cells from the inner cell mass of an early-stage embryo that can differentiate into various cell types.

What is a key difference between eukaryotic and prokaryotic cells regarding DNA?

Eukaryotic cells have a nucleus that contains their DNA, while prokaryotic cells have DNA in a nucleoid region without a membrane.

How do enzymes function in biochemical processes?

Enzymes act as catalysts to speed up reactions by lowering the activation energy required.

What is the role of mitochondria in a cell?

They are the site of aerobic respiration and ATP production.

Define homeostasis.

Homeostasis is the maintenance of a constant internal environment despite changes in the external environment.

Explain the process of photosynthesis briefly.

Photosynthesis is the process by which photoautotrophs convert light energy, water, and carbon dioxide into glucose and oxygen.

What is the difference between primary and secondary succession?

Primary succession occurs in lifeless areas; secondary succession occurs in areas where a disturbance has left the soil intact.

How do antibodies function in the immune response?

Antibodies are produced by the immune system to specifically recognize and neutralize foreign antigens like pathogens.

Describe the term biodiversity.

Biodiversity is a measure of the variety of living organisms within a particular habitat, ecosystem, biome, or across the planet.

What is selective breeding?

Selective breeding is the intentional mating of organisms with desirable traits to produce offspring with those desirable traits.

Describe the process of natural selection.

Natural selection is the process where individuals with traits best suited to their environment survive and reproduce more successfully.