HESI Biology AND Anatomy Study
Guide
Hesi A2 Entrance Exam (Chamberlain University)
,BIOLOGY
Taxonomy:
is the classification of living and extinct organisms, otherwise known as biological
classification or the hierarchic organizational system.
- Kingdom
- Phylum
- Class
- Order
- Family
- Genus
- Species
Cells:
Organelles
Nucleus: the cell’s “command center”, stores the cell’s DNA. Controls all of
the cell’s activities, such as growth and metabolism, using the DNA’s
genetic information. Within the nucleus is a smaller structure called the
nucleolus
Nucleolus: houses the RNA (ribonucleic acid). RNA helps convey the DNA’s
orders to the rest of the cell and serves as a template for protein
synthesis.
Ribosomes: translates instructions to produce proteins, read RNA produced in
the nucleus and translate instructions in order to produce proteins, Bound
ribosomes can be found in the endoplasmic reticulum and Free ribosomes can
be found in the cytoplasm
Rough ER: are studded with ribosomes and are involved with protein manufacture.
Smooth endoplasmic reticulum (SER) function involves manufacturing and packaging,
including the synthesis of lipids and hormones which are used for the production of new
cellular membranes.
Golgi apparatus(“post office of the cell”) : responsible for packaging proteins into
vesicles and sending them out to the correct destinations within the cell, where the
proteins are used to carry out the requisite cellular functions.
Mitochondria: facilitate the production of ATP, the main source of chemical energy in
living organisms.
, Chromatin: efficiently package DNA into a small volume to fit into the nucleus of a cell
and protect the DNA structure and sequence. Packaging DNA into chromatin allows for
mitosis and meiosis, prevents chromosome breakage and controls gene expression and
DNA replication.
Plasma Membrane: A double layer of lipids that separates the cell interior from
the outside environment. This double layer consists largely of specialized lipids
called phospholipids.
Reproduction:
Sexual Reproduction: Meiosis
Asesual Reproduction: Mitosis and Binary fission
Which stage of mitosis is occuring when the chromosomes begin
separating and the chromatids are considered separate chromosomes?
Anaphase
DNA:
Four nitrogen bases of DNA: Adenine, Thymine, Guanine, and Cytosine (AT,
GC)
- When DNA molecules make copies of themselves, they expose their nucleotide
bases. With the nucleotide bases exposed, new DNA nucleotides bind to them
through obligatory base pairing, which is coordinated with DNA polymerase. This
process forms two new DNA molecules, which are distributed to two daughter
cells.
Ribonucleic acid (RNA): is a molecule that acts as the genetic code's messenger.
- Four bases: adenine, guanine, cytosine, and uracil
genetic expression:
- multiple alleles
- Pleiotropy: production by a single gene of two or more apparently
unrelated effects.