Biology 30 Review

What is the main goal of the nervous system in relation to homeostasis?

To contribute to homeostasis through signaling and regulation.

What is the structure of a neuron primarily composed of?

Dendrites, a cell body, and an axon.

What do action potentials represent?

Rapid electrical signals that travel along the axon of a neuron.

What is the role of neurotransmitters?

Chemical messengers that transmit signals across synapses between neurons.

What is a reflex arc?

A neural pathway that controls a reflex action.

Differentiate between the Peripheral Nervous System and the Central Nervous System.

The Central Nervous System consists of the brain and spinal cord, while the Peripheral Nervous System includes all other neural elements.

What is the primary function of the brain in the CNS?

To process information and coordinate responses.

What is the role of the spinal cord in the CNS?

To transmit signals between the brain and the rest of the body.

What structures compose the Peripheral Nervous System?

Nerves and ganglia outside the brain and spinal cord.

What is the function of the eye in sensory perception?

To detect light and facilitate vision.

How does the ear function in sensory perception?

To detect sound waves and aid in balance.

What are the main components of the endocrine system?

Endocrine glands that secrete hormones.

What role do hormones play in the body?

They regulate physiological processes and maintain homeostasis.

What is a negative feedback loop?

A mechanism that reverses a change in a controlled condition to maintain homeostasis.

How do the endocrine and nervous systems interact?

They work together to regulate bodily functions and maintain homeostasis.

What can result from hormone imbalances?

Disruptions in growth, metabolism, and reproductive health.

What is the primary function of progesterone?

To prepare the endometrium for a fertilized egg to implant.

What are the roles of estrogen in the female reproductive system?

It develops female sexual characteristics and regulates menstrual cycles.

What is FSH and its main purpose?

Follicle-Stimulating Hormone (FSH) stimulates ovarian egg production and regulates the menstrual cycle.

What is the main function of testosterone?

Regulates sex drive, fat distribution, and production of sperm.

How do birth control pills work?

They contain synthetic hormones that prevent ovulation.

What is the corpus luteum's primary function during pregnancy?

Secretion of progesterone to maintain pregnancy.

What does implantation refer to in pregnancy?

The attachment of the fertilized egg to the uterine wall.

Name the three germ layers and what they develop into.

Ectoderm (skin and nervous system), mesoderm (muscles and bones), endoderm (digestive and respiratory systems).

What is the role of the placenta during pregnancy?

To provide nutrients and oxygen to the fetus and remove waste products.

What is meiosis?

A type of cell division that produces gametes with half the number of chromosomes.

What is mitosis?

Cell division that results in two identical daughter cells with the same chromosome number.

What does ploidy refer to?

The number of sets of chromosomes in a cell.

Differentiate between diploid and haploid cells.

Diploid cells contain two sets of chromosomes, while haploid cells contain one set.

Define gametes and somatic cells in terms of ploidy.

Gametes are haploid (n), while somatic cells are diploid (2n).

How does meiosis contribute to genetic diversity?

Through crossing over and independent assortment.

What is crossing over?

The exchange of genetic material between non-sister chromatids during meiosis.

What are Mendel's Laws of Inheritance?

Law of Dominance, Segregation, and Independent Assortment.

What is the law of dominance?

In hybrid offspring, the dominant trait is expressed in the phenotype.

What does the law of segregation state?

Alleles segregate so that offspring acquire one allele from each parent.

What is the law of independent assortment?

Traits are inherited independently during gamete formation.

What is the difference between genotype and phenotype?

Genotype refers to the genetic makeup, while phenotype is the observable expression.

What is the significance of linkage in genetics?

Linked genes are inherited together, but crossing over can separate them.

What relationship exists between the number of genes and trait variability?

More genes lead to greater variability in traits.

What distinguishes sex-linked traits from autosomal traits?

Sex-linked traits are located on sex chromosomes, whereas autosomal traits are on non-sex chromosomes.

What historical event is associated with the discovery of DNA?

Watson and Crick's discovery of the double helix structure in 1953.

What is the structure of DNA?

A double helix formed by two strands of nucleotides.

How is genetic information stored in DNA?

In the sequence of nucleotides along the DNA strands.

What are the steps involved in DNA replication?

The unwinding of the double helix, pairing of nucleotides, and forming new strands.

What are the effects of mutations on DNA?

They can lead to new genes that alter an organism's traits.

Where is DNA found within a cell?

In the nucleus, mitochondria, and chloroplasts.

What is the 'universal language' of DNA?

It is the common genetic code that relates organisms to each other.

What is insulin and its primary function?

Insulin is a hormone produced by the pancreas that regulates blood glucose levels by facilitating the uptake of glucose into cells.

What role does glucagon play in the body?

Glucagon is a hormone that raises blood glucose levels by promoting the conversion of glycogen to glucose in the liver.

What are the functions of cortisol?

Cortisol is a stress hormone that helps regulate metabolism, reduces inflammation, and assists in the body's response to stress.

What is the function of adrenaline (epinephrine)?

Adrenaline prepares the body for 'fight or flight' responses by increasing heart rate, blood flow to muscles, and energy production.

What is oxytocin's role in the human body?

Oxytocin is often called the 'love hormone' and is involved in childbirth and bonding, promoting uterine contractions during labor and milk ejection during breastfeeding.

What does thyroid hormone regulate?

Thyroid hormones, primarily thyroxine (T4) and triiodothyronine (T3), regulate metabolism, energy production, and influence growth and development.

What is the function of parathyroid hormone (PTH)?

Parathyroid hormone regulates calcium levels in the blood, mainly by increasing levels when they are low.

What roles does calcitonin play in the body?

Calcitonin helps to lower blood calcium levels by inhibiting bone resorption and promoting calcium excretion in the kidneys.

What is the main function of aldosterone?

Aldosterone helps regulate sodium and potassium levels in the blood, which influences blood pressure.

How does growth hormone (GH) affect the body?

Growth hormone stimulates growth, cell reproduction, and regeneration, affecting muscle mass and fat distribution.

What is the role of luteinizing hormone (LH) in reproduction?

Luteinizing hormone triggers ovulation in females and stimulates testosterone production in males.

What is DNA transcription?

The process of converting a segment of DNA into RNA.

What enzyme is primarily responsible for DNA transcription?

RNA polymerase.

What are the three main stages of transcription?

Initiation, elongation, and termination.

What is the role of mRNA in translation?

To carry the genetic information from DNA to the ribosome, where proteins are synthesized.

What are codons, and why are they significant in translation?

Codons are sequences of three nucleotides on mRNA that encode for specific amino acids during protein synthesis.

What is the purpose of DNA replication?

The purpose of DNA replication is to produce two identical copies of DNA from one original DNA molecule, ensuring that genetic information is accurately passed on during cell division.

What proteins are involved in DNA replication?

Key proteins involved in DNA replication include helicase (unwinds the DNA), DNA polymerase (synthesizes new strands), and ligase (joins Okazaki fragments on the lagging strand).