Biology Lecture Notes: Cells, Homeostasis, Reproduction, Genetics, and Ecology

Comprehensive vocabulary flashcards covering basic cell biology, life functions, reproduction, genetics, evolution, and ecology concepts as presented in the lecture notes.

Homeostasis

The ability of an organism to maintain a stable internal balanced environment; failure can result in sickness or death.

Metabolism

The sum of all the chemical reactions that occur within the cells of an organism.

Organic Molecules

Molecules containing skeleton structures of carbon with hydrogen and oxygen.

Glucose (Simple Sugars)

The basic unit of carbohydrates (starch) found in foods like grains, vegetables, and fruit.

Amino Acid

The basic unit of proteins; there are $20$ kinds found in foods like meat, egg whites, and beans.

Fatty Acid & Glycerin

The basic units of lipids found in animal fats, nuts, and oils.

Nucleotide

The basic unit of nucleic acids, found in small amounts in all foods.

Organelles

The small parts that make up a cell, each having at least one specific function.

Vacuoles

Organelles that store waste and water; they are large in plant cells and small in animal cells.

Ribosome

A very small organelle where proteins are made (protein synthesis) located on the ER or in cytoplasm.

Mitochondria

The powerhouse of the cell where energy is made; the site of cellular respiration in both plant and animal cells.

Formula for Cellular Respiration

$$Glucose + oxygen \rightarrow carbon dioxide + water + ENERGY (ATP)$$

Chloroplasts

Organelles found only in plant cells where the process of photosynthesis occurs.

Formula for Photosynthesis

$$Sun's energy + carbon dioxide + water \rightarrow glucose + water + oxygen$$

Nucleus

The control center of the cell that contains DNA, which is the program or code of life.

Cell Membrane

Structure that separates cell contents from the environment and controls material transport using selective permeability.

Passive Transport or Diffusion

The movement of molecules from areas of high concentration to areas of low concentration without using energy.

Active Transport

The movement of molecules from low concentration to high concentration which uses energy in the form of $ATP$.

Hormones

Control chemicals produced in the endocrine glands responsible for communication between cells.

Digestion

The process of breaking large molecules down into smaller molecules, such as proteins into amino acids.

Synthesis

The process of making or building large molecules from smaller ones.

Enzymes

Special protein catalysts that affect the rate of chemical reactions; they are affected by shape, temperature, and pH.

Dynamic Equilibrium

A steady state-balance, also known as homeostasis.

Negative Feedback

A mechanism that controls hormone levels, such as the pancreas secreting insulin to lower high blood glucose levels.

Insulin

A hormone secreted by the pancreas when glucose levels are above normal to prompt glucose movement from blood into cells.

Antigens

Surface receptor proteins on the membrane of pathogens (germs) that the immune system recognizes as outside invaders.

Antibodies

Special proteins produced by white blood cells with specific shapes that fit over antigens to block pathogens.

Vaccination

A treatment composed of a weakened or dead virus that triggers white blood cells to produce antibodies.

Mitosis

Asexual reproduction consisting of one cell division producing two identical daughter cells with a diploid number ($2n$).

Meiosis

Sexual reproduction consisting of two cell divisions producing four sex cells with a haploid number ($1n$).

Gonads

The sex glands, specifically the ovaries in females and the testis in males.

Gametes

Sex cells that unite in fertilization to form a zygote.

Zygote

A fertilized egg resulting from the union of a male and female gamete.

Differentiation

The process that transforms developing cells into specialized cells with different structures and functions.

Placenta

An organ attached to the baby via the umbilical cord that provides nutrients and oxygen through diffusion.

Karyotype

A visual map of chromosomes used to identify chromosomal problems like Down's syndrome.

Cancer

A condition occurring when genetic mutations result in uncontrolled cell division.

Heredity

The passing of genetic information from one generation to the next through reproduction.

DNA

A double stranded helix polymer of nucleotides containing the genetic code.

Clones

Identical genetic copies of an organism.

Mutation

Any alteration of the DNA sequence, including substitution, deletion, addition, or inversion.

Genetic Engineering

Technology used by humans to alter the genetic instructions in organisms.

Gene Splicing

A type of genetic engineering involving cutting DNA and placing it into another organism.

Restriction Enzyme

An enzyme that cuts DNA in specific places; a tool used in gene splicing and gel electrophoresis.

Natural Selection

The process by which nature selects individuals who are best fit for the environment.

Adaptive Value

Any trait that helps an organism survive and reproduce under a given set of environmental conditions.

Biodiversity

A measurement of the degree to which species vary within an ecosystem; species variety increases ecosystem stability.

Carrying Capacity

The maximum population of any species that an ecosystem can support.

Energy Pyramid

A diagram showing available energy where the amount decreases by $90\%$ at each level as you move up.

Ecological Succession

The orderly sequence of changes in communities in an ecosystem over time, from pioneer organisms to a climax community.

Acid Rain

Rain with a low pH caused by sulfur and nitrogen compounds in air pollution dissolving in atmospheric moisture.

Independent Variable

The one factor changed in an experiment to test a hypothesis, graphed on the X-axis.

Dependent Variable

The data collected in an experiment that changes because of the independent variable, graphed on the Y-axis.

Paper Chromatography

A laboratory technique used to separate different molecules from one another by size and color.

Gel Electrophoresis

A technique used to separate DNA fragments using electrical current by size to show how species are related.