Genetics and General Histology Overview

A specific sequence of DNA that encodes a protein or functional RNA. They are the basic units of heredity, determining traits.

A variant form of a gene. They are the different versions of a gene that can cause variations in a trait.

An allele that is expressed in the phenotype even if only one copy is present. It masks the recessive allele.

An allele that is only expressed when two copies are present. It is masked by the dominant allele.

The genetic makeup of an individual, determined by the specific alleles they carry.

The observable physical or biochemical characteristics of an organism, resulting from the interaction of its genotype with the environment.

States that each individual receives one allele for a trait from each parent, and these alleles separate during gamete formation.

States that genes for different traits are inherited independently of each other, as long as they are located on different chromosomes.

The branch of biology that studies heredity and variations in organisms, focusing on how traits pass from parents to offspring.

The fundamental units of heredity that carry genetic information from parents to offspring.

The molecule that stores and transmits genetic information, composed of nucleotides with four nitrogenous bases: adenine, thymine, cytosine, and guanine.

Chromosomes are structures in eukaryotic cells that tightly package DNA, forming chromatin.

A visual representation of an individual's chromosomes arranged in pairs by size and shape, showing the number and arrangement of chromosomes.

Humans have 23 pairs of chromosomes, including 22 pairs of autosomes (non-sex chromosomes) and one pair of sex chromosomes (X and Y).

The complete set of genetic instructions in an organism, consisting of approximately 3 billion base pairs of DNA organized into 23 pairs of chromosomes.

The study of the human genome provides insights into genetic diversity, the basis of inherited traits, and the potential for personalized medicine.

Changes in the DNA sequence of genes that can alter their function. These alterations can be spontaneous or caused by environmental factors.

Genes that regulate cell growth and division, preventing uncontrolled proliferation. When mutated, they can lose their function, leading to cancer.

Genes that promote cell growth and division. When mutated, they can become overactive, leading to uncontrolled cell growth and cancer.

A genetic disorder characterized by the production of thick, sticky mucus that clogs the lungs and other organs.

A genetic disorder that causes red blood cells to be sickle-shaped, leading to oxygen deprivation and pain.

A genetic disorder that causes progressive neurodegeneration, leading to movement problems, cognitive decline, and psychiatric issues.

An X-linked recessive disorder that affects blood clotting, leading to excessive bleeding.

A type of tissue that covers body surfaces, lines cavities, and forms glands. It acts as a protective barrier and is involved in absorption, secretion, and sensation.

A type of tissue that provides structural support, binds tissues together, and stores energy. It includes bone, cartilage, blood, and adipose tissue.

A genetic disorder that primarily affects males, causing muscle weakness and progressive loss of muscle function.

A type of tissue responsible for movement and force generation. It includes skeletal, cardiac, and smooth muscle.

A type of tissue that transmits electrical impulses and processes information. It consists of neurons and supporting glial cells.

A single layer of epithelial cells.

Multiple layers of epithelial cells.

Epithelial cells with cilia that move mucus and trapped particles out of the airways.

Mucus-secreting cells found in the lining of the intestines and respiratory tract.

A different form of a gene, leading to variations in traits. An individual receives one allele from each parent.

A mutation that changes one base pair to another without changing the amino acid sequence. It has no effect on the protein.

The expression of both alleles in a heterozygote, resulting in a phenotype that combines both traits.

A condition where both alleles for a trait are expressed, but the resulting phenotype is a blend of the two.

The condition when multiple genes contribute to a single trait, leading to continuous variation.

The inheritance pattern where one gene's expression masks another gene, affecting a different trait.

This tissue covers body surfaces and lines internal cavities. Composed of tightly packed cells with little extracellular matrix.

These cells are responsible for synthesizing extracellular matrix in connective tissues, contributing to its structural integrity.

Simple squamous epithelium is thin and composed of a single layer of flattened cells, allowing for efficient exchange of substances. This makes it ideal for diffusion and filtration.

Connective tissue provides support, protects organs, and stores energy reserves. However, it does not directly secrete hormones. That function is typically associated with glands.

Hemophilia is an X-linked recessive disorder, meaning a mother carries the gene and can pass it on to her sons. A son has a 50% chance of inheriting the disorder.

Cilia are hair-like structures in the respiratory tract that sweep mucus and debris out of the airways. Smoking damages these cilia, reducing their ability to clear the airways, increasing the risk of infections and lung diseases.

Adipocytes store fat, osteocytes are found in bone, and chondrocytes reside in cartilage. None of them play a primary role in synthesizing the extracellular matrix of connective tissue.

The epithelium lining the respiratory tract contains cilia that help move mucus and debris out of the airways. Smoking damages these cilia, making the airways more vulnerable to infections.

Transitional epithelium is found in organs that need to stretch, like the bladder. It's not the best for diffusion, as its layers of cells are thicker and more complex.