Chapter One: Under the Microscope
What are the qualities of living things?
Living things have various qualities which are: they need raw materials and energy, undergo metabolism, can
respond to their environment. Living things can maintain homeostasis which means they can maintain a
constant internal environment despite changes in the external environment, undergo growth and reproduction,
can evolve and are made of various molecules to include proteins, carbohydrates, nucleic acids, and lipids.
Describe prokaryotic vs. eukaryotic cells.
Prokaryotic cells have a nucleus that is not bound by a membrane and have few organelles or none, and an
example is bacteria. On the other hand, eukaryotic cells have a nucleus which is secured by a membrane and
poses many organelles like the ribosomes, mitochondria, and vesicles among others and an example is a human
List the organelles and their functions.
The organelles of eukaryotic cells are: The Nucleus which is the cell's brain holds it directs DNA and all cell
activities. The ribosomes are responsible for energy production, Endoplasmic reticulum which are rough and
smooth. The rough assist in the production of proteins while the smooth produces lipids primarily. The Golgi
apparatus is another organelle whose function is to refine, ship and package products form the endoplasmic
reticulum. The Mitochondria acts as the cell's powerhouse and is involved in the production of ATP molecules.
The other organelles are the vesicles which serve as storage, endocytic and secretory organelles and contain
lysosomes and peroxisomes.
List and describe the four primary tissue types.
The first tissue type is epithelial which covers the cavities of the body, lines surface s and organs and the
glandular epithelium is involved in the production of secretions. The second tissue type is the connective tissue
whose function is to support and connect and is classified into loose, dense, adipose, cartilage, blood and bone.
Thirdly is the Muscular tissue which contracts to allow various forms of movement and includes the cardiac,
smooth and skeletal muscles. Lastly is the nervous tissue which provides communication by transmitting and
List the components of a negative feedback loop and their role.
There are four components of a negative feedback loop which are: the controlled variable which is the element
that is specifically being monitored, the sensors which are receptors that are special and are used for variable
monitoring. The other is the control center which is given input by the sensors and determines response and the
Effectors whose role is to carry out response that is necessary to bring about balance
Chapter Two: Holding it together
What are the characteristics of the epidermis?
The epidermis is the top layer of the skin that is visible. It is made up of stratified squamous epithelium which
can be thin or thick. Its cells which include the basal cells and the keratinocytes are continuously made and
replaced. The epidermis is the primary defense line, gives color to the skin and protects it from the sun. Also
contains Melanocytes. The epidermis also contains some immune cells that are stationed throughout.
Describe keratinocytes vs. melanocytes.
Keratinocytes are cells that die out and dry as they rise to the surface of the skin. They produce a protein that is
hard and waterproof known as keratin. Melanocytes, on the other hand, produce melanin pigment that is dark
which gives the skin its color and protects it from the sun.
What are the characteristics of the dermis and which structures contribute to them?
The dermis detects and regulates temperature via the help of the sweat glands, erector pili muscle, and
thermoreceptors. This layer also gives shape and pliability to the skin through the elastin and collagen fibers and
dermal papillae which is responsible for fingerprints. The dermis has a blood supply that is ample for all the
cells and takes in sensory stimuli via the action of nerves and receptors. The dermis also aids in immunity and
protection through the production of sebum that limits the growth of fungi and bacteria and the abundant blood
supply also brings in other cells that are immune.
How many bones are in the human body?
The body contains around 206 bones
How bone is is formed?
Bone formation begins with a mold of cartilage where hyaline cartilage is laid down by chondroblasts during
development. Osteoblasts, which are cells that build bone, are brought in by incoming blood supply. Mineral
matrix is laid down by the osteoblasts, which also release enzymes to harden it into bone, a process known as
ossification. Osteoblasts ...