Biology/Ecology Study Guide

Cell Cycle Order

Interphase, Mitosis, and Cytokinesis

Mitosis Order

Interphase, Prophase, Metaphase, and Anaphase

Interphase

* DNA is copied in S Phase
* Nuclear Membrane Still Exists
* DNA is Chromatin

Prophase

* Spindle Fibers start forming
* Chromatin is Chromosomes
* Nuclear Membrane disappears

Metaphase

* Chromosomes line up
* Spindle Fibers connect

Anaphase

* Chromosomes are pulled apart

Telophase

* The Nuclear Membrane comes back
* Spindle Fibers leave
* Chromosome → Chromatin

Incomplete Dominance

* Not completely dominant
* Example: black, white, gray| red, white, pink

Codominance

* Equally Dominant
* Example: Speckled Black and White| Blood Types

Colorblindness

* X-Linked Recessive
* The inability to distinguish certain colors

Hemophilia

* X-Linked Recessive
* A rare disorder in which the blood doesn't clot in a typical way because it doesn't have enough blood-clotting proteins.

Cystic Fibrosis

* Autosomal Recessive
* Cystic fibrosis affects the cells that produce mucus, sweat, and digestive juices. It causes these fluids to become thick and sticky. They then plug up tubes, ducts, and passageways.

Sickle Cell Anemia

* Autosomal Recessive
* A group of disorders that cause red blood cells to become misshapen and break down.
* Abnormal Hemoglobin

Albinsim

* Autosomal Recessive
* affects the production of melanin, the pigment that colors skin, hair, and eyes.

Phenylketonuria

* Autosomal Recessive
* A rare inherited disorder that causes an amino acid called phenylalanine to build up in the body.
* No diet soda

Huntington’s Disease

* Autosomal Dominant
* An inherited disorder that causes nerve cells (neurons) in parts of the brain to gradually break down and die.

Homologous Chromosomes

Same genes, different alleles

Diploid Cells

* Homologous Pairs
* Makes Body Cells
* 2n

Haploid Cells

* One of each
* Sex Cells
* n

Meiosis I

Homologous Chromosomes are separated reducing chromosome numbers in half

Meiosis II

Sister Chromatids are separated making four haploid gametes

Trisomy 21

* Down Syndrome
* During Anaphase II, split wrong

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Nondisjunction

Chromosomes did not separate during Meiosis

Klinefelter’s Syndrome

* Nondisjunction
* Male
* Doesn’t go through puberty

Turner’s Syndrome

* Monosomy, missing one copy
* Female
* Doesn’t go through puberty

Base Pairs

* Adenine → Thymine
* Cytosine → Guanine
* The “rungs” of DNA structure

Hydrogen Bonds

hold together Base pairs

What does DNA stand for?

Deoxyribonucleic acid

DNA Structure

see image