BIOL Exam 3

Fertilization

fusion of gametes to form a zygote

Somatic cell

body cell (diploid)

Germ cell

gives rise to gametes

Gamete

sex cell (haploid)

Aneuploidy

abnormal chromosome number (ex: Down syndrome)

Polyploidy

extra full sets of chromosomes (common in plants)

Mitosis

growth/repair, diploid → diploid, identical cells

Meiosis

gamete formation, diploid → haploid, genetic variation

Crossing over

exchange of DNA between homologous chromosomes

Independent assortment

random chromosome distribution

Genetic variation

comes from crossing over, independent assortment, fertilization

If sex chromosomes don’t separate

disorders like Turner or Klinefelter

Asexual

one parent, identical offspring

Sexual

two parents, variation

Hermaphroditism

both sex organs (intersex in humans)

Spawning

release of gametes into water

Stem cells

undifferentiated cells

Gonad

produces gametes

Spermatogenesis

sperm production

Oogenesis

egg production

Environmental sex determination

temperature affects sex (ex: turtles)

Internal fertilization

inside body

External fertilization

outside (spawning animals)

the role gene expression plays in differentiation of stem cells into specific tissues and organs

Gene expression controls cell differentiation.

how reproductive tissue typically differentiates during development

Hormones guide reproductive development

Metabolism

all of the biochemical reactions occurring within a cell/organism

Energy

ability to do work

Enzyme

speeds reactions

Catabolic

break down, release energy

Anabolic

build up, store energy.

Glycolysis

primitive, produces ATP and pyruvate.

how it is known that glycolysis is a primitive metabolic pathway and name the products

it is a universal pathway found in nearly all living organisms

Aerobic Respiration

makes most ATP using oxygen

Anaerobic

fermentation (lactic acid), less ATP than aerobic respiration.

Main energy carrier

ATP

Photoautotroph

makes food using light

Photosynthesis formula

6CO2 + 6H2O + light → C6H12O6 + 6O2

Chlorophyll

absorbs light

Describe the relationship between pigments, the electromagnetic spectrum and photosynthesis. Know which pigment is used in plant photosynthesis

Photosynthetic pigments, primarily chlorophylls, absorb specific wavelengths of electromagnetic radiation (light) to power photosynthesis.

Light-independent reactions:

Calvin Cycle -> Carbohydrates from Carbon dioxide.

Regenerates the ADP and NADP+ for use in the light-dependent reactions.

Chemical inputs: CO2, ATP, NADPH.

Outputs: C6H12O6, ADP, NADP+

Light-Dependent Reactions

Pigments absorb energy and an electron gets energized.

When the water gets split, O2 is released.

Chemical Inputs: H2O, ADP, NADP+

 Outputs: O2, ATP, NADPH

Describe the transformation of energy in photosynthesis from photons to glucose, including the energy carriers that connect light dependent and independent reactions

Energy flows from light → ATP/NADPH → glucose

Enzymes

Enzymes are proteins

Carbon fixation

CO2 into organic molecules (inorganic to organic compounds using photosynthesis)

RuBisCo

enzyme for carbon fixation (most abundant protein on Earth)

Cyanobacteria

similar to chloroplasts (endosymbiosis)