Lecture 1: The organization of life – From atoms to the biosphere

Life is defined by seven characteristics, including Organization, Homeostasis, Metabolism, Growth, Reproduction, Adaptation, and __.

Responsiveness

The basic unit of life is the __.

cell

An atom consists of a dense central __ surrounded by a cloud of electrons.

nucleus

Orbitals have different electron capacities: Orbital 1 can hold __ electrons.

2

Orbitals have different electron capacities: Orbital 2 can hold __ electrons.

8

Orbitals have different electron capacities: Orbital 3 can hold __ electrons.

8

The periodic table arranges elements by increasing __ (Z).

atomic number

A full valence shell makes an atom __.

unreactive

Covalent bonds involve the sharing of a pair of __ electrons by two atoms.

valence

Hydrogen bonds are electrostatic forces between a partially negatively charged atom (O or N) and a partially positively charged hydrogen that is covalently bound to a/an __.

oxygen

Ionic bonds involve the transfer of an electron, resulting in a positively charged atom () and a negatively charged atom ().

cation; anion

Carbon can make up to __ bonds.

4

Nitrogen can make up to __ bonds.

3

Oxygen can make up to __ bonds.

2

Sulfur can make up to __ bonds.

2

Phosphorus can form up to __ bonds.

5

The four main biomolecules are carbohydrates, nucleic acids, proteins, and __.

lipids

Carbohydrates are built from monomers called __.

monosaccharides

The organelle where cellular respiration occurs and most ATP is generated is the __.

mitochondrion

The nucleus houses the genetic material and is bounded by the __.

nuclear membrane

Ribosomes are complexes that synthesize __.

proteins

The membrane enclosing the cell is the __.

plasma membrane

The network of membranous sacs and tubes involved in membrane synthesis and other metabolic processes is the __.

endoplasmic reticulum

The organelle responsible for processing, sorting, and shipping cell products is the __.

Golgi apparatus

The four main animal tissue types are epithelial, connective, muscle, and __.

nervous

A tissue is an ensemble of similar cells from the same origin that together carry out a specific __.

function

Organs are formed by the functional grouping together of multiple __.

tissues

Humans have __ organ or body systems.

11

Leaves form part of the plant's __ system.

shoot

The upper epidermis of a leaf has a waxy coating called the __.

cuticle

The palisade mesophyll contains __ and performs photosynthesis.

chloroplasts

The stomata are formed by guard cells and allow CO2 to enter and O2 to exit; these pores are called __.

stomata

The four tissue layers of the small intestine are mucosa, submucosa, muscle layer, and __.

serosa

The small intestine is part of the __ system.

digestive

The biosphere is divided into large __, such as tundra, grassland, forests, deserts, and aquatic biomes.

biomes

LUCA stands for __.

Last Universal Common Ancestor

Prokaryotic cells lack a true __.

nucleus

Eukaryotic cells have a true nucleus enclosed by a __.

nuclear membrane

Plants have a rigid outer layer called the __.

cell wall

Chloroplasts originated from an ancient __ bacterium.

cyanobacteria

The nucleus contains chromatin, which is DNA and __.

proteins

The digestive organelle where macromolecules are hydrolyzed is the __.

lysosome

The cytoskeleton includes microfilaments, intermediate filaments, and __.

microtubules