A&P 2: Development & Hereditary (Vocabulary/Short Answer)

Prenatal Period

Describes approximately 38 weeks of development inside the mother's uterus.

Postnatal Period

Describes the time from birth all the way through all the life stages; often referred to as the short period following birth.

Diploid

Are the result of when gametes combine; the resulting zygote will have 46 chromosomes.

Haploid

Genetically unique sex cells produces by meiosis (producing gametes) that have 23 chromosomes; half of the body's cells.

Fertilization

The process of the fusion of a sperm cell with a secondary oocyte to form a zygote.

Zygote

Initial cell formed when a perm cell fertilizes an ovum; single-celled structure that contains 46 chromosomes (23 from each parent), which ensures the correct genetic makeup for developing a new individual; undergoes cleavage.

Cleavage

A series of rapid mitosis division that produce small, genetically identical cells called blastomeres; cells numbers increase, but the cell size becomes progressively smaller.

Implantation

A process that occurs approximately 4-7 days after fertilization; blastocyst begins to attach to the endometrium of the uterus.

Morula

The early developing conceptus composed of 16 of more cells; remains covered by the zona pellucida; "little mulberry."

Blastocyst

Hatches from thr zona pellucida and that blastomeres reorganize to surround an internal fluid-filled cavity; early stage of development during which implantation occurs.

Chorion

The outermost of the extra-embryonic membranes that develop during early embryogenesis; plays a crucial role in enclosing the conceptus and other membranes; important for the placenta.

Placenta

A temporary organ that is the site of the exchange of oxygen, nutrients, and wastes between the mother and fetus; produces hormones to support the pregnancy.

Pre-Embryonic Period

Lasts for the first 2 weeks of fertilization; zygote divides mitotically many times; produces an intracellular structure that implants in the endometrium of the uterus.

Gestation Period

The period that extend from the mother's last menstrual period until birth, which is approximately 280 days or 40 weeks; is longer than the prenatal period.

Embryonic Phase

Extends from 3 through week 8 of gestation; conceptus grows, folds, and forms rudimentary organ system; "embryo."

Fetal Phase

Lasts from week 9 through week 38 of gestation or until birth; conceptus is "fetus"; grows and develops organ systems/functions.

Totipotent

Have the ability to potentially develop into any cell type in the body; cell is known as zygote.

Pluropotent

Type of stem cell that have the ability to differentiate into almost any cell type in the body; are crucial in the development of an organs because they can give rise to various tissues and organs.

Multipotent

Type of cells that are limited within a particular lineage or tissue; crucial role in the body's ability to repair and regenerate tissues.

Endoderm

The innermost germ layer of an embryo; replaces the hypoblast.

Mesoderm

The middle layer of an embryo; via cells migration to a position between the epiblast and endoderm.

Ectoderm

The outermost layer of an embryo; via the remaining cells of the epiblast forming structure.

Organogensis

Occurs after the cephalocaudal and transverse folding have completed; takes place during which the three primary germ layers differentiates into organs and organ systems.

Parturition

When the fetus is expelled from the uterus through the vagina; series of events are collectively called labor.

Infancy

Lasts from 1 month through 2yrs.

Childhood

Lasts until the onset of sexual maturity or puberty; marks the beginning of adolescences.

Adolescence

Extends from approximately ages 10-19.

Puberty

A developmental stage where children transition into adulthood, which is marked by the physical and hormonal changes; begins typically for boys (8-14 yrs) & girls (9-16 yrs).

Adulthood

Extends from the end of adolescence to death.

Genetics

Study of heredity and how it is transmitted.

DNA

The hereditary material in humans and almost all other organisms; carries the genetic information crucial for the growth, development, functioning, and reproduction of all living things.

Chromosome

Structures within cells that contain DNA; typically 46, from 23 organized pair; determine the sex.

Chromatin

A complex of DNA and proteins found in the nucleus of cells; plays a crucial role in packaging the long strand of DNA strands into a compact, organized form that fits within the nucleus.

Transcription

Process in gene expression, where DNA is converted into mRNA, which then guides protein synthesis; produces proteins necessary for function like gamete production and hormone regulation.

Translation

Process apart of protein synthesis, where the genetic code is carried by mRNA to be decoded into specific sequences of amino acids, forming a polypeptide; occurs within the ribosomes.

Genome

The complete set of DNA within an organism; encompasses all of its genes.

Dominant Trait

Trait that is expressed in the phenotype even if only one dominant allele is present in the genotype.

Recessive Trait

Trait that is not expressed when dominant is present as much; a characteristic that is expressed in an individual only when two receive alleles are present.

Genotype

An individuals genetic makeup.

Phenotype

The physical expression of an individual's genotype in the form of a trait.

X Chromosome

Chromosome that contains 5x more genes; female attributes.

Y Chromosome

Chromosome that contains less genes; male attributes.

Mutation

Changes in the DNA sequence that can lead to genetic disorders.

Epigenetic

Changes in gene expression that do not involve alteration to the underlying DNA sequence; influenced by environmental factors.

50%

What are the odds that parents will have an Aa baby?

1. Dad = AA

2. Mom = Aa

25%

What are the odds that the flower will have rr offspring?

1. Red Flower = RR

2. Pink Flower = Rr