Human Reproduction, Genetics, and Evolution Lecture Notes

Vocabulary flashcards covering human reproduction, cellular genetics, inheritance, variation, and the evidence/mechanisms of evolution.

Testicles

Organs that produce sperm and testosterone.

Scrotum

Loose skin behind the penis that holds the testicles outside the body and regulates temperature.

Sperm ducts

The passage between the testes and the urethra that sperm travels through.

Prostate gland

Gland that adds nutrients to sperm to create semen.

Urethra

The tube through which sperm travels from the bladder to exit the penis.

Penis

An organ that can become firm for insertion into the vagina to pass sperm to the female.

Ovaries

Organs that hold all the eggs a woman will need in her life.

Oviducts (Fallopian tubes)

Tubes that allow the egg to travel from the ovaries to the uterus for fertilization.

Uterus

A muscular wall where a fetus grows during pregnancy.

Cervix

A ring of muscle that separates the vagina from the uterus.

Vagina

The part of the female reproductive system where the male penis is received during intercourse and sperm is released.

Gametes

Human sex cells, specifically the sperm and the egg.

Fertilization

The process where a sperm and egg fuse together to create a zygote.

Zygote

The cell formed by fertilization that multiplies as it travels through the oviducts.

Embryo

The stage of development that occurs when a zygote attaches to the wall of the uterus.

Fetus

The stage of development inside the womb after the embryo stage.

Haploid cells

Sex cells that each contain $23$ chromosomes.

Diploid cells

Body cells, also known as somatic cells (found in blood and skin), which have a full set of $46$ chromosomes.

Genes

A specific section of DNA.

Chromosomes

Structures located inside the nucleus of a cell made up of tightly coiled DNA.

DNA

A double helix structure that looks like a twisted ladder made up of bases.

DNA Bases

The components of DNA where Guanine pairs with cytosine and thiamine pairs with adenine.

Human genome

The total amount of genetic information in the human species.

Mutation

A change, loss, or alteration to a gene of the DNA.

Examples of mutations

Being born legless, being born blind, or being born deaf.

Causes of genetic mutations

Factors including smoking or vaping, drugs, pollution, and physical inactivity.

Genotype

The genetic coded information inside the DNA.

Phenotype

A physical trait that is seen by others.

Cell

The basic building blocks of life that make up everything in the body.

Allele

A different form of a gene.

Characteristic

A trait that a person has, such as eye color.

Dominant

A trait that overpowers and masks a recessive one.

Recessive

A trait that only appears if an individual inherits two copies of it.

Punnett squares

A tool used to show how genes are inherited by displaying all possible outcomes for offspring based on the alleles of two parents.

Variation

Differences in transgenetics or behavior between different organisms caused by genetic changes and environmental factors.

Discrete variation

Characteristics controlled by a single gene that are not influenced by the environment, such as eye color.

Continuous variation

Characteristics controlled by a few or more genes that can be influenced by the environment or change over time, such as height.

Mitosis

A process starting with one cell with $46$ chromosomes that duplicates its DNA and divides to end with two identical daughter cells.

Meiosis

A process starting with one cell with $46$ chromosomes that mixes DNA, splits twice without copying DNA a second time, and ends with four daughter cells with $23$ chromosomes each.

Evolution

When a species changes over time through generations by inherited modifications.

Selective breeding

When humans intentionally breed organisms, such as chickens or apples, to enhance or develop a certain trait.

Darwin's Theory of Survival

The idea that organisms with traits best suited to their habitat are more likely to survive and reproduce.

Importance of Variation

Ensures that a whole population is not wiped out by a single threat, as some individuals may have natural immunity.

Diversification

When one species splits into more different new species over time to fill different roles in nature.

Fitness

A measure of how well an animal can survive and reproduce in the wild.

Scientific theory

An search for an explanation or an educated guess backed by evidence and facts.

Finch Beak Evidence

Evidence for evolution showing that birds on different islands adapted different beaks based on their diet and environment to efficiently get food.

Desert Mice Evidence

Evidence for evolution where mice adapted darker coats over time to blend into surroundings turned black by a volcano eruption $1000$ years ago.

Peppered Moth Evidence

Evidence for evolution where moths adapted from lighter to darker colors during industrial times to blend in with soot-covered environments and avoid predators.