Biology Lecture Notes Flashcards

Flashcards based on biology lecture notes focusing on hormones, circadian rhythms, karyotypes, mitosis, meiosis, and asexual reproduction.

Hormones

Chemicals that help regulate our bodies, mostly for homeostasis; influenced by our environment and the way we live.

Melatonin

Hormone released in the evenings for sleep.

Cortisol

Hormone that peaks in the morning to help you wake up.

Leptin

Hormone associated with weight gain.

Serotonin

Hormone associated with mood (content/happiness).

Circadian Rhythm

Internal clock for most organisms, usually reset by light exposure, typically on a 24-hour schedule; needed for overall organism health.

SCN (Suprachiasmatic Nucleus)

Brain area that controls the circadian rhythm.

Karyotype

A picture of all chromosomes in the body, helpful for studying chromosome structures and identifying genetic disorders.

Mitosis

Regulated cell division that results in 2 somatic (body) daughter cells, each containing 46 chromosomes (diploid, 2N); cells are genetically the same (clones).

Interphase

Phase of the cell cycle where DNA is copied in the nucleus; accounts for 90% of the cell growth cycle.

Prophase

Phase of mitosis where DNA condenses to form chromosomes, visible under microscopes; chromosomes migrate towards the middle of the cell.

Metaphase

Phase of mitosis where chromosomes line up in the middle of the cell and attach to fibers to the edges.

Anaphase

Phase of mitosis where chromosomes move away from each other towards opposite sides of the cell.

Telophase

Phase of mitosis where the nucleus starts to reform around chromosomes, and the cell starts to cleave/split in the middle.

Cytokinesis

Phase of mitosis where the cell fully cleaves in 2, resulting in 2 genetically identical daughter cells (diploid, 2n/46 chromosomes).

Meiosis

Regulated cell division for the exclusive synthesis (production) of sex cells, resulting in 4 gametes, all containing 23 chromosomes (haploid: n) with varying genetic information.

Asexual Reproduction

Reproduction where all genetic information is passed on to offspring; common in various organisms like bacteria, strawberries, starfish, and bees.

Fragmentation

A type of asexual reproduction where offspring are made from cut-up pieces. Ex: Starfish/flatworms

Binary Fission

A type of asexual reproduction where an organism makes a copy & rips itself in two. Ex: bacteria

Budding

A type of asexual reproduction where offspring grow from the side of the parent & fall off. Ex: hydra, yeast

Spores

A type of asexual reproduction where particles which can spread in air. Ex. Fungi, bacteria

Vegetative Propagation

A type of asexual reproduction mostly for plants, Plant your plants= more plants