Year 11 Double Biology Exam Review

Flashcards for key concepts, definitions, and processes in Year 11 Double Biology.

Classification system

A system based on morphological features or DNA analysis.

Five kingdoms

Bacteria, single-celled organisms, plants, fungi, and animals.

Hierarchical order of classification

Kingdom, phylum, class, order, family, genus, species.

Biodiversity

The variety of different species and numbers of individuals within those species in an area.

Importance of biodiversity

It provides food, potential foods, industrial materials and new medicines.

Methods of conserving biodiversity

Seed banks, national parks, and captive breeding programs.

How to use quadrats

Measure area, randomize coordinates, count organisms, calculate mean, multiply by site area.

Line transect method

Place a tape measure on the ground and count organisms at regular intervals.

Capture/recapture technique

A method to count the number of moving organisms.

Assumptions of capture/recapture

No death, immigration, emigration, and marking does not affect survival chance.

Alien species

A species introduced into an area where it does not naturally occur.

Biological control

The control of a pest by the introduction of a natural enemy or predator.

Research before biological control

To assess effects and ensure it does not become a pest.

Chromosomes

Linear arrangements of genes found in pairs in the nucleus.

Mitosis function

Growth, repair, and asexual reproduction.

Meiosis function

Formation of gametes for sexual reproduction.

Process of mitosis

The genetic material is copied and the cell divides into two genetically identical cells.

Process of meiosis

The cell divides twice to make four gametes, each with a single set of chromosomes.

Cancer

The result of uncontrolled mitosis.

Stem cells

Cells from human embryos and bone marrow capable of becoming specialized cells.

Advantages of using own stem cells

No rejection, no need for a donor, no tissue typing needed.

Ethical issues of stem cells

Cells come from embryos, which are potential human life.

DNA structure

Two chains of sugar and phosphate alternating, twisted into a double helix.

Four bases of DNA

Adenine, thymine, cytosine, and guanine.

Importance of base order

Determines the order of amino acids linked to form proteins.

Triplet code

Sequence of three bases that identifies a particular amino acid.

Genetic profiling

Cutting DNA into pieces that are then separated into bands for comparison.

Ethical issues surrounding genetic profiling

Information may be stored on databases or used for insurance and job applications.

Gene

A section of DNA that determines an inherited characteristic.

Allele

A different form of an individual gene.

Gamete

A sex cell (egg or sperm) that contains half the number of chromosomes of a body cell.

Dominant allele

An allele that will be expressed if present.

Recessive allele

An allele that must be present in two copies to be expressed.

Genotype

The alleles present (e.g., Bb).

Phenotype

The physical characteristic (e.g., brown hair).

F1 and F2 generations

F1 is the first filial generation and F2 is the second generation.

Genetic modification

The artificial transfer of genes from one organism to another.

Advantages of genetic modification

Disease resistance and increased yield.

Disadvantages of genetic modification

Unknown health effects and environmental impact.

Continuous variation

Type of variation showing a large range of differences.

Asexual reproduction

Type of variation producing clones.

Mutation

A random change in DNA.

Factors increasing mutation rates

Ionizing radiation; higher doses increase mutation chance.

Cystic fibrosis

A recessive inherited disease that produces thick mucus blocking bronchioles.

Cystic fibrosis treatment

Gene therapy via inhalers.

Human genome research aims

To develop new treatments for diseases.

Natural selection

Individuals with advantageous characteristics are more likely to survive and reproduce.

Proposers of natural selection theory

Charles Darwin and Alfred Wallace.

Examples of ongoing evolution

Antibiotic resistance in bacteria and warfarin resistance in rats.

Causes of species extinction

Natural selection being too slow for adaptation to environmental changes.

Organs controlling blood glucose levels

The pancreas releases insulin and glucagon; liver and muscles respond to them.

Diabetes

A condition with high blood sugar levels; Type 1 due to insulin lack, Type 2 due to cell response failure.

Glucose testing solution

Benedict's solution turns yellow/red in presence of sugar.

Stimuli for sense organs

Light, sound, touch, temperature, and chemicals.

CNS components

Brain and spinal cord.

Properties of reflex actions

Fast, automatic, and often protective.

Components of the reflex arc

Stimulus, receptor, sensory neurone, relay neurone, motor neurone, effector, and response.

Synapse

A gap between neurones where messages are transferred by chemicals.

Homeostasis

Maintaining temperature, pH, sugar, and water levels within a narrow range.

Hormones

Chemical messengers secreted by glands and transported in the blood.

High blood sugar response

Pancreas releases insulin, liver converts glucose to glycogen.

Temperature regulation mechanisms

Changes in blood vessel diameter, sweating, hair erection, and shivering.

Long-term effects of alcohol

Liver disease, heart disease, and circulatory issues.

Four types of microbes

Bacteria, fungi, viruses, and protists.

Pathogen

A micro-organism that causes disease.

Bacterial cell structure

Consists of cell wall, cell membrane, cytoplasm, and no distinct nucleus.

Virus structure

Gene surrounded by a protein coat.

Communicable disease spread methods

Contact, aerosol, body fluids, water, insects, and contaminated food.

Body defense mechanisms

Intact skin, blood clots, phagocytes, lymphocytes.

Antigen

A molecule recognized by the immune system, triggering antibody production.

Antibiotics

Medicines produced by living organisms to combat bacteria.

Overuse of antibiotics consequences

Evolution of resistant bacteria like MRSA.

Control measures for MRSA

Hand washing, cleaning hospital wards, using alcohol gels, screening.

Drug development duration

Long due to potential side effects requiring extensive testing.

Issues surrounding drug testing

Testing on animals may raise ethical concerns.

Vaccine definition

Usually dead or weakened microorganisms with antigens to stimulate immune response.

How we become immune

Memory cells retain information for rapid antibody production upon re-exposure.