Unicellular organisms include bacteria, protists, and yeast. For example, a paramecium is a slipper-shaped, unicellular organism found in pond water. It takes in food from the water and digests it in organelles known as food vacuoles. Nutrients from the food travel through the cytoplasm to the surrounding organelles, helping to keep the cell, and thus the organism, functioning. Multicellular organisms are composed of more than one cell, with groups of cells differentiating to take on specialized functions. In humans, cells differentiate early in development to become nerve cells, skin cells, muscle cells, blood cells, and other types of cells. One can easily observe the differences in these cells under a microscope. Their structure is related to their function, meaning each type of cell takes on a particular form in order to best serve its purpose. Nerve cells have appendages called dendrites and axons that connect with other nerve cells to move muscles, send signals to glands, or register sensory stimuli. Outer skin cells form flattened stacks that protect the body from the environment. Muscle cells are slender fibers that bundle together for muscle contraction. The cells of <u>multicellular</u> organisms may also look different according to the organelles needed inside of the cell. For example, muscle cells have more mitochondria than most other cells so that they can readily produce energy for movement; cells of the pancreas need to produce many proteins and have more <u>ribosomes</u> and rough <u>endoplasmic</u> <u>reticula</u> to meet this demand. Although all cells have organelles in common, the number and types of organelles present reveal how the cell functions.
Hope that helps!!
1.Proteins. Proteins are found in the blood plasma and all over the body. The functions of protein include: repair and maintenance of body tissue, they are components of some hormones e.g. insulin, they make up enzymes, they make up transport molecules such as hemoglobin.
Lipids. These are used for energy storage and production. They provide energy for muscle and body processes.
Starch. Starch is converted into glucose for energy in the body.
Sugar . Sugar in the form of glucose is used by every cell in the body for energy.
Calcium. A mineral that is used by the body for building and keeping bones and teeth strong.
Chloride (NOT chlorine)ion. Acts as an electrolyte in the body.
Iron. Iron is an essential element of hemoglobin in the red blood cells .
Answer:
d. Expressivity refers to the range of expression of a given phenotype.
e. Penetrance refers to the percentage of individuals that expresses the mutant phenotype.
Explanation:
Penetrance is the probability of a gene being expressed. Sometimes, phenotype is not observed even when the dominant allele is present. It is a result of various genetic and environmental factors coming together.This phenomenon is called as incomplete or reduced penetrance. For example: polydactyly trait is produced by a dominant allele but its penetrance is low in general population hence few people show this trait.
Expressivity is the variation in phenotypic expression when an allele is penetrant. Same genetic combination for a trait can have different expressivity in the same population. This phenomenon is also a result of genetic and environmental factors acting together. For example: people who do end up showing polydactyly trait may show it to different degrees. Some might have one extra finger, some might have two. Some might have a stub, some might have a full grown finger.
<span>fenestrated glomerular capillary endothelial cells, basal lamina, podocytes. </span>
