Compendium 10,11 & 12

What happens in telophase?

Nuclei reform.

What happens in meiosis I?

Homologous chromosomes separate.

What is the endocrine system?

A system of glands that releases hormones into the bloodstream.

What is a hormone?

A chemical messenger carried in the blood.

What body functions do hormones regulate?

Metabolism, growth, reproduction, stress, water balance, and temperature.

Which gland is known as the master gland?

Pituitary gland.

Which structure controls the pituitary gland?

Hypothalamus.

What is a receptor?

A protein that binds a specific hormone.

What is a tropic hormone?

A hormone that stimulates another endocrine gland.

What is a non-tropic hormone?

A hormone that acts directly on target cells.

What does TSH stand for?

Thyroid Stimulating Hormone.

What does ACTH stand for?

Adrenocorticotropic Hormone.

What does LH stand for?

Luteinising Hormone.

What does GH stand for?

Growth Hormone.

What does TSH stimulate?

Release of T3 and T4 from the thyroid.

What do T3 and T4 regulate?

Metabolism.

What is the role of aldosterone?

Water and sodium balance.

What does FSH do in females?

Stimulates oocyte development.

What does LH do?

Stimulates sex hormone production.

What is prolactin's function?

Milk production.

What does MSH affect?

Skin pigmentation.

What does ADH do?

Promotes water retention.

What does oxytocin do?

Stimulates uterine contractions and milk ejection.

What is neural stimulation?

Hormone release triggered by nerve impulses.

What is hormonal stimulation?

Hormone release triggered by another hormone.

What is humoral stimulation?

Hormone release triggered by blood chemistry changes.

Give an example of negative feedback.

Thyroid hormone regulation.

Give an example of positive feedback.

Oxytocin during labour.

What pathway regulates cortisol?

CRH → ACTH → Cortisol.

What causes Addison's disease?

Low cortisol production.

What causes hyperthyroidism?

Excess thyroid hormone.

What causes hypothyroidism?

Low thyroid hormone.

What causes Type 1 diabetes?

Insufficient insulin production.

What is insulin's role?

Lowers blood glucose.

What is glucagon's role?

Raises blood glucose.

What are the three main functions of the lymphatic system?

Fluid balance, lipid absorption, and immunity.

What is lymph?

Fluid that travels through lymphatic vessels.

What do lymphatic capillaries do?

Collect excess interstitial fluid.

What do lymph nodes do?

Filter lymph and house immune cells.

Which immune cells are found in lymph nodes?

Macrophages and lymphocytes.

What is innate immunity?

Non-specific defence present from birth.

What is adaptive immunity?

Specific immunity with memory.

What is the second line of defence?

Inflammation, fever, and phagocytosis.

What is the third line of defence?

Adaptive immune response.

What causes swelling during inflammation?

Fluid leakage into tissues.

Why is fever beneficial?

Enhances immune activity and slows pathogen growth.

What is cellular immunity?

T-cell mediated immunity.

What are T cells responsible for?

Destroying infected cells.

What are memory T cells?

T cells that respond rapidly to future infections.

What is humoral immunity?

B-cell and antibody-mediated immunity.

What do B cells become after activation?

Plasma cells.

What do plasma cells produce?

Antibodies.

What are antibodies?

Proteins that bind specific antigens.

What is an antigen?

A foreign substance that triggers an immune response.

What is a primary immune response?

The first exposure to a pathogen.

Why is the secondary response faster?

Memory cells are present.

What are microorganisms?

Microscopic living organisms.

What is a pathogen?

A disease-causing microorganism.

Name a beneficial role of microorganisms.

Food production or decomposition.

What factors affect microbial growth?

Temperature, pH, moisture, nutrients, oxygen.

How can pathogens spread?

Contact, droplets, airborne, fecal-oral routes.

What did the Glo Germ experiment demonstrate?

Rapid spread of microorganisms through contact.

Why is skin important in immunity?

It acts as a physical barrier.

What is active immunity?

Immunity produced by one's own immune system.

What is passive immunity?

Receiving antibodies from another source.

What is natural active immunity?

Immunity after infection.

What is artificial active immunity?

Immunity after vaccination.

What is natural passive immunity?

Maternal antibodies.

What is artificial passive immunity?

Injected antibodies.

Which type of immunity forms memory cells?

Active immunity.

Which type provides immediate protection?

Passive immunity.

What is the most effective way to prevent infection spread?

Hand hygiene.

What is a gene?

A DNA sequence that codes for a protein.

What are proteins made of?

Amino acids.

What is the secondary structure of a protein?

Alpha helices and beta pleated sheets.

What is the tertiary structure of a protein?

Three-dimensional folding.

What is a polypeptide?

A longer chain of amino acids.

What are nucleic acids?

DNA and RNA.

What are the three parts of a nucleotide?

Sugar, phosphate, nitrogenous base.

What are DNA base pairing rules?

A-T and C-G.

What are RNA base pairing rules?

A-U and C-G.

How many strands does DNA have?

Two.

How many strands does RNA have?

One.

What is a codon?

A three-base sequence coding for an amino acid.

What is an anticodon?

A three-base sequence on tRNA.

What is the start codon?

AUG.

Name the stop codons.

UAA, UAG, UGA.

Where does transcription occur?

Nucleus.

What is translation?

mRNA used to make protein.

Where does translation occur?

Ribosomes.

What is mRNA?

Messenger RNA.

What is rRNA?

Ribosomal RNA.

What is gene expression?

Transcription and translation.

Why do cells become specialised?

Different genes are expressed.

How many chromosome pairs do humans have?

23 pairs.

How many autosome pairs do humans have?

22 pairs.

What are the sex chromosomes?

XX or XY.

What is a diploid cell?

A cell with 46 chromosomes.

What is a haploid cell?

A cell with 23 chromosomes.

What are sister chromatids?

Two identical chromatids joined together.