WK2 How do cells do what they do? Flashcards
What makes up the environment of a cell?
Organelles
What are the main organelles inside a cell and what is their function?
Plasma membrane - encloses and supports content, regulating the movement of intra and extracellular material
Cytoplasm - holds cytosol and organelles. Produces inclusions such and melanin and glycogen.
Cytoskeleton- manages and maintains the structure or framework of the cell
Nucleus- The control center of the cell containing genetic information (DNA). The DNA defines how the cell operates and functions.
Ribosomes- Where protein synthesis occurs as a result of amino acid chainwork
Golgi apparatus- Responsible for preparation, modification, and transportation of proteins, lipids, steroids, and carbohydrates produced by the Endoplasmic reticulum.
Lysosomes- Responsible for digesting waste products not required by the cell
Mitochondria- Produces and supplies ATP(adenosine triphosphate) which is the energy used by the cell
Centrioles- Responsible for pulling cells apart creating cell division
Cilia- Responsible for moving substances across the surface
Microvilli- increases the surface area of the cell to optimize absorption
What happens to a cell if an organelle stops working?
Cell will likely die and go into autophagy (where body re-uses old or damaged cell parts)
Are all cells in the body the same?
No
What are the four primary tissue types?
Epithelium- covers. Lines tubes of our body, lines our body
Connective- supports. Holds our skeleton together
Smooth muscle- movement. Expands and contracts and supports movement
Nervous- control. Neurons and supporting cells govern our body sending messages throught the different areas
What are the general characteristics and functions of epithelia? where are they found
Covers and protects surfaces internally and externally. Made mostly of cells, covers body surfaces, often have an exposed surface, specialised cell connections, nonvascular, regenerative.
Found covering tubes, skin, sweat glands, salivary duct glands, mammery gland ducts, portion of male urethra,etc
What types of cell surface modifications are found in epithelia and what is their function?
Surface modifications include 1 or more layers of cells – simple, stratified and pseudo stratified; and 1 or more cell types squamous, cuboidal and columnar
What are the 3 types of simple epithelia? Give an example of where they are found and how are they adapted for their specific function.
Simple Squamous - Diffusion, filtration, some secretion, some protection against friction
Simple Cuboidal - Secretion and absorption by cells of the kidney tubules, secretion by cells of glands, movement of particles embedded in mucous out of the terminal bronchioles
Simple Columnar - Movement of particles o9ut of the bronchiolse of the lungs by ciliatd cells, responsible for movement of oocytes through uterine tubes bi ciliated cells, secretion by cells of the glands, stomach, intestines; absorption of the small and large intestine
What are the two main types of stratified squamous epithelia? Give an example of where they are found and how are they adapted for their specific functions?
Keratinised and non keratinised. Skin (keratinised) and mouth (covers mucosa). The nature of this multi layered tissue to provide protection against abration, barrier against infection and reduce water loss of the body
What are the general characteristics of connective tissue?
Few cells, and a lot of extra cellular matrix, very diverse in structure and function
How do the general characteristics of connective tissues compare with those for epithelia?
The opposite of epithelia where there exists a lot of cells and little extra cellular matrix
Name the 3 types of muscle found in the body and briefly describe their functions?
Skeletal – responsible for moving our skeletal structure, very important for heat regulation, metabolism, posture ad breathing. Regenerative.
Cardiac – contract, generating a force which moves blood through arteries, also changing rate and force depending on needs of body
Smooth – Regulates the size of organ or tube to help move contents of tube (blood vessel) along
What are the general characteristics of nervous tissue?
Nervous tissue mainly consists of Neurons (nerve cells) and supporting cells (neuroglia)
