science pt reviewer

Estrogen

A hormone that influences bone density, cholesterol levels, cognitive function, and cardiovascular health; types include estrone, estradiol, and estriol.

Estradiol

The most potent type of estrogen during reproductive years.

Progesterone

A hormone that prepares the uterine lining for implantation and maintains pregnancy.

LH (Luteinizing Hormone)

A gonadotropin that triggers ovulation in females and stimulates testosterone production in males.

Testosterone

A male hormone important for sperm production, muscle mass, and secondary sexual characteristics.

Adrenaline (Epinephrine)

A hormone released during the 'fight-or-flight' response, increasing heart rate and blood pressure.

Thyroxine (T4)

The primary thyroid hormone that regulates metabolism and affects nearly every cell in the body.

Insulin

A hormone produced by the pancreas that regulates blood glucose levels.

Cortisol

The primary stress hormone that regulates metabolism and immune response.

Oxytocin

Often referred to as the 'love hormone', involved in social bonding and childbirth.

PMS (Premenstrual Syndrome)

A condition characterized by mood swings and physical symptoms related to the menstrual cycle.

PCOS (Polycystic Ovary Syndrome)

A hormonal disorder causing cysts on the ovaries, irregular periods, and elevated androgen levels.

Endometriosis

A condition where uterine tissue grows outside the uterus, causing inflammation and pain.

Gonorrhea

A bacterial STI that can lead to serious reproductive complications if untreated.

HPV (Human Papillomavirus)

A common viral STI that can cause genital warts and cervical cancer.

Syphilis

A bacterial STI that progresses through multiple stages, potentially causing serious health issues.

Negative feedback

A mechanism where a change triggers responses that counteract the change, like temperature regulation.

Positive feedback

A mechanism that amplifies a process, like oxytocin release during childbirth increasing contractions.

Cerebrum

The largest part of the brain, divided into lobes with specialized functions such as memory and decision-making.

Cerebellum

The part of the brain responsible for coordination, balance, and some cognitive functions.

Brainstem

Controls vital functions like breathing and heart rate, consisting of the midbrain, pons, and medulla oblongata.

Hypothalamus

A link between the nervous and endocrine systems that regulates hormone release.

Thalamus

A relay station for sensory information in the brain.

Homeostasis

It is maintained by negative feedback loops within the organism. In contrast, positive feedback loops push the organism further, but may be necessary for life to occur. It is controlled by the nervous and endocrine systems in mammals.

What is the difference between positive and negative feedback in homeostasis?

Positive feedback increases or amplifies something, while negative feedback decreases or reduces something.

Neurotransmitter

Chemicals that transmit signals across synapses between neurons.

Signal transmission

The process whereby neurotransmitters influence the postsynaptic neuron, initiating or inhibiting signals.

Sympathetic Nervous System

Part of the autonomic nervous system that prepares the body for action (fight-or-flight response).

Parasympathetic Nervous System

Part of the autonomic nervous system that promotes relaxation and digestion.

DNA Replication

The process of copying DNA to produce two identical DNA molecules.

Transcription

The process of synthesizing mRNA from DNA.

Translation

The process of synthesizing proteins from mRNA at the ribosome.

Point mutation

A change affecting a single nucleotide in DNA.

Silent mutation

A point mutation that does not change the amino acid sequence.

Missense mutation

A point mutation that results in the substitution of one amino acid for another.

Nonsense mutation

A point mutation that creates a premature stop codon, truncating the protein.

Frameshift mutation

A mutation caused by insertion or deletion of nucleotides, altering the reading frame of codons.

Biodiversity

The variety of life forms on Earth.

Fossil Record

Chronological sequence of life forms preserved in rocks that provides evidence for evolution.

Comparative Anatomy

The study of similarities and differences in the anatomy of different species, suggesting common ancestry.

Embryonic Development

The early stages of development that show similarities between different species, indicating common ancestry.

Amino Acid Sequences

The arrangements of amino acids in proteins that can be compared across species to find evolutionary relationships.

Geologic Time Scale

A system that categorizes Earth's history into different periods based on fossil evidence and rock layers.

Neuron

A specialized cell that transmits nerve impulses throughout the body.

Axon

The long projection of a neuron that carries impulses away from the cell body.

Dendrite

Branch-like structures of a neuron that receive signals from other neurons.

Myelin Sheath

A fatty layer that insulates axons and increases the speed of neural impulses.

Synapse

The junction between two neurons where neurotransmitters are released to transmit signals.

Electrochemical Signal

The combination of electrical impulses and chemical signals that carry messages within the nervous system.

Resting Membrane Potential

The electrical charge difference across the neuron's membrane when the neuron is not active.

Neuroplasticity

The ability of the brain and neurons to reorganize and form new connections in response to learning or injury.

Resting Potential

The state of a neuron when its membrane maintains a negative charge inside compared to the outside due to the unequal distribution of ions maintained by ion pumps.

Action Potential

An electrical signal generated when a stimulus causes depolarization, allowing sodium ions to rush into the neuron and creating a positive charge.

Neurotransmitter Release

The process that occurs when the action potential reaches the axon terminal, triggering the release of neurotransmitters into the synaptic cleft.

Signal Transmission

The mechanism where neurotransmitters bind to receptors on the postsynaptic neuron, resulting in either excitation or inhibition.

Postsynaptic Neuron

A neuron that receives signals from another neuron via neurotransmitter binding, affecting its excitability.

Synaptic Cleft

The small gap between the axon terminal of one neuron and the dendrites of another where neurotransmitters are released and received.

Hypothyroidism

A condition in which the thyroid gland does not produce enough thyroid hormones, leading to symptoms such as fatigue, weight gain, and sensitivity to cold.

Hyperthyroidism

A condition where the thyroid gland produces excessive amounts of thyroid hormones, leading to increased metabolism and various symptoms such as weight loss, rapid heartbeat, and anxiety.

Hyperglycemia

A condition characterized by excessively high levels of glucose in the blood, often associated with diabetes and leading to symptoms like increased thirst and frequent urination.